How To Install an Ultra Efficient Heating System - Heat Pump + UFH.
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- čas přidán 3. 12. 2023
- #heatpump #airsourceheatpump #vaillant
In this video, I take you through a full installation of a heating system with an air source heat pump and UFH throughout a property undergoing major renovations.
For booking contact me here:
www.urbanplumbers.co.uk/ - Jak na to + styl
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I want to thank you for sharing your knowledge. You saved me €600 on my gas bill this year. I saw a video of yours last year and started working on it. I converted my entire house to low temperature heating in combination with a 2 year old intergas extreme 36 and went from 1100m³ to 500m³ of gas per year. The intergas extreme 36 runs at its lowest power setting with a pump speed of 55% and a supply temperature of 35 degrees and return around 28 degrees with a flue gas temperature of 25 degrees. And the best part is that my house heats up faster and easier compared to the old underfloor heating distributor and a supply temperature of 65 degrees. Thanks again!!! And continue with your CZcams Channel
Greetings from Holland
It’s not full savings right? You did spend much more than 400€ investing to have such system right? I’m curious how long would it break even though 😊
It costs me €1200,-.
But the savings are 600m³ a €1,30 ( the price in Holland) = €780.
Break even in 1,5 year
that is awesome @@douwekannis3146 🙌
Hi. How was your heating system configured initially and what exactly have you changed ? Thank you !
Interesting experiment. Read gas meter, collect all condensate for 4 hours or so and measure collected volume and gas consumption. 100% condensation should yield 1600 mls of condensate per cubic metre of gas. My system does 1.15 l/m3.
The way in which you make these videos informative, accessible and engaging to both heating engineers and non-technical experts like myself is a real skill and I really appreciate the way in which you embed learning into these case studies - in this case the calculation of appropriate flow rates for the calculated heat loss. If you told me two years ago that I'd be seeking out videos on CZcams about heating systems, I wouldn't have believed you! So thanks for all you're doing to share your developing expertise to help educate, inform and entertain folk from some many different backgrounds like myself.
Mate, theres no denying you know your stuff, excellent design to be honest. If only every house could get this amount of insulation. Would love to know the budget for that install.
That pipework is a work of art! 😊❤
Inspiringly clear. Thank you!
Great video Simon. Simple solution, perfectly executed.
Great video as usual 👍 looking forward to the next one (particularly the eps cavity wall insulation one)
Great install Szymon and team. Another happy customer I’m sure 👌
One of the best videos you have done and I been following you for many years
Wow, neat pipework...😮
You are THE go to installer without doubt!
Thanks again for another excellent video. Always learn from you, its great.
Wow - great project, thank you for posting
Another great video! Thanks for sharing your knowledge and experience.
Great video. I am currently designing a heat pump system for my house renovation. The pipework walk through at the end was informative and helpful as this system is incredibly similar to what I have come up with for my house.
Beautiful work, planning something very similar in our retrofit. Hopefully we can find someone as skilled in Scotland to make our design as simple.
I have an air to air heat pump that achieves a cop of 4.8 and cools as well as heats. If you can consider separating your hot water system from your heating system, air to air heat pumps become very attractive. Various methods are then available for hot water such as a thermino sunamp. It’s seems to be a very UK thing that people generally can’t imagine separating hot water systems from heating systems.
I agree, but one problem we have in the UK (say compared to the USA) is that our houses are typically much smaller, and have much less room available for additional systems. The availability of ducted heat pumps that can sit on top of the hot water cylinder save space, and allow the seperation of flow temperatures that is critical to maintaining the best COP for each application (space heating vs. DHW production). The down side is the extra cost. However, the cost of DHW cylinders with coils suitable for heat pumps are not cheap, so the difference in cost might be recoverable over the life of the systems. The other problem is that there are then two heat pumps to go wrong/need servicing. The Sunamps have a poor record of reliability.
@@tlangdon12 Great points. On the space issue we have a smaller 2 bedroom uninsulated old property and I was able to work out a way of integrating a ductless air to air system, without removing our gas combo boiler (which does only hot water now until we replace that system). I had to put time and effort into the placement. The ductless pipework doesn’t take up much internal space but requires real thought on placement and the condensate also requires thought. We laid the pipes in between the joists. I’ve not heard of ducted heat pumps on top of hot water cylinder, I will have to research those out of interest, I guess I didn’t come across them as we don’t have a hot water cylinder (no space). In terms of functionality I presume they won’t do cooling. Also I wonder how much fine tuning is required o have a balanced system with those. The thing I like about the air to air ductless system is they are capable of easily heating and cooling uninsulated spaces, the air to water systems are so fine tuned with much more risk of running inefficiently or the house being too cold when set up. I see most businesses use air to air, I am not sure why the air to water is pushed so hard for homeowners in the UK, my presumption being someone at the top thought “this will be easiest just swap out boiler for this single unit”, when in reality they are very complex fine tuned systems and not as high cop!
Why doesn’t one of the air to air manufacturers bring out an exchanger for heating water, would make great sense for uk market, could just connect as a refrigerant zone.
@edc1569 they do make them already
@@edc1569 it will lower the performance you can achieve for the indoor units of the air to air system and lower the overall COP of the system as exchanging to water is inefficient. Also due to them not being capable of achieving instant hot water would require a cylinder which in a lot of cases people may not have space to accommodate.
Thanks for sharing that. Very nice setup.Would be interested to know how close the temperatures of the room stabilise compared the design temperatures. Also, glad to see that the MVHR has been taken into account for ventilation heat losses (and curious what airtightness level they were able to achieve)
If you spend enough time adjusting it at the design temp it will be spot on.
Love the simplicity of this install!Currently in the middle of a restoration/selfbuild of 100m2 single story.UFH pipes are installed but I've been spec'd with room stats and actuators etc...also a buffer tank.Prefer the idea of keeping it a simple open system.Maybe I dont have the system volume?
Just done my calculation for 7800w at -3 got a flow of 1337 per hour. Thanks for the help to understand flow + temps.
heatpunk states the same vaillant 7kw system
That was excellent 👏👏. Thank you
Work of art🎉
Great video.
It's nice to see a proper design done on the installation.
Tidy pipework too.
The vailant looks like a nice unit, better than the mitsubishi.
Much, much better than mitisi in my opinion
Fascinating insight. Thank-you. What I'd really like to know is the cost of that system...
Outstanding as always, I hope at some point in the next few years to be going this way
Excellent video! Very useful. Could you please tell us more about the UFH pipes used? Max length, diameters, etc?
I like it. No buffer, no actuators, UFH design tailored to the max. efficiency. Question: I have the same setup of UFH but designed for a gas boiler with dT 45/35. Only one heating circuit with two manifolds for each floor. Can a heat pump replace a gas boiler without using a buffer?
Thank you for sharing your knowledge!
Can you tell me, how to compensate for the variations and errors in UFH pipe laying, if there are no thermostats?
If a room is designed to be piped 150mm CTC, does it matter if it gets 130 at some points, then 170 at others?
Don't you use balancing valves, when you pipe two manifolds to one pump, like a STAD valve?
Hi Simon, could you run the primaries in MLCP? Are there are disadvantges with MLCP with heat loss? I suspect they would have to be sized up as the walls are thicker.
We have a dual spilt air to air heat pump. The house is open plan on two levels. Insulation is average to very good. It was -9 C last Sunday morning. The heat pump is set at 45% power demand. The house stayed at 20 C and the external compressor had little to no ice on it. The electrical heat pump consumption for that 24 hours was 13.4kW. We pay 0.17€ per kWh so = 2.28€ before tax. I can't buy wood to burn for that. Not that I would burn carbon fuels. Just shows how efficient HPs are. Keep up the good work.
Great vid as always. Quick question as I'm looking at a 20 W/m2 property (280 m2) with all UFH with 3 manifolds. With the low power requirement then the flow rates in each loop are theoretically less than 1 1/min, i.e. laminar flow. Is that a problem ? Given ~ 680 l/hr, and it looks like perhaps greater than 16 loops in your install, then the average would also be less than 1 l/min. I see that you've used different spacing depending on load/covering - but can't see how that avoids the low flow rates - or am I over thinking the effects of laminar flow ?
Hi just found your channel which I have learned so much from ,so thank you. I have been looking at ways to improve efficiency with my gas boiler and through watching your videos now realise that it is far to big.We moved into the house 4 years ago and a new boiler had been fitted "Ideal Vogue Max 40" it is a 5 bedroom house and well insulated built around 2009. I purchased 2 nest stats to run UFH and Rads but because there were 2 zone valves I was informed that open therm could not be used.
I had the nests installed but basically it appears to be an on off system?. The boiler currently runs at 50 degrees but cycles ie the flame symbil disappears and then comes back on.
1- could I use weather compensation and would it worth the purchase and cost of install?
2- Would it help in anyway to reduce cycling and bills
3- Could you advise on any further steps I could make.
I live in central Scotland any feedback would be greatly appreciated.
Regards
Hi great video as always, do you set the heat pump controls to be on all the time or is it on a timer? And for example, heating water aside, on the warmer days when my heating would be completely off all day and night would you have the heat pump off? Thanks
Great video
Thanks!
When you said its all open loop, im guessing there is some allowance for opening/closing the room valve on the manifold if someone ends up wanting their bedroom more at 16 than 18 etc then adjusting pump speed if needed, then the overall temp of the property is more of a master control.
Great video,,,,that heat pump ,,,the main electric/ supply from PV ?
Cracking video !
Thank you!
Pleased to see our products being utilised on the project Szymon
What are your thoughts on not having insulation on pipework. Would the benefits of heat gains from pipework cost less than energy spent.
Vaillant was my preferred brand here in the USA but isn’t available here anymore. Any idea what might compare that would be available to me here?
What you've described makes Engineering sense.
In 5 years, the "EPC" box ticket will degrade the 'points', because the manifold didn't have 'heating controls' 😂
I don't understand why air ducted heating isn't promoted, as a reversing valve air con unit can provide heating and cooling on the same system.
air ducts take up a lot of space, we don't really need cooling in the UK
+ forced air heating is noisy.. it was a thing in the 70s and didn't catch on
@@MichaelFlatman I'm not sure I would agree that we don't need cooling in the UK. Every heat wave we have causes excess deaths in older people that have a lower tolerance to very high temperatures.
This system can also provide cooling via MVHR and W2A heat exchanger - video on another house with that set up coming soon. You can also cool via UFH
The idea is we are supposed to be using less energy, If everybody had A/C in the summer we would be using a lot more energy as a nation.
@@93jsaw with adequate ventilation you rarely need cooling
I think the govt wants to stop people building in tightly insulated boxes running aircon in summer when a bit of ventilation would go a long way to getting rid of the heat
What would you then do for instance, if the bedroom requires a higher temperature for a shorter period?
When the temperature control is based on flow and heat-loss from the initial setup of the system.
I love what you are doing, and getting deeper into how to build efficient heating systems!
Just get an electric fan heater for an hour
Why not suggest to just increase the flow for an hour in that room and increase the flow a bit from the main system? Just a curious elec Engineer..
These videos are great, well presented and informative. What I take away is that ASHP works very well with well insulated homes. So governments should be addressing this issue along side encouraging the adaptation of this heating source. I’m seriously considering converting my 60’s bungalow that has an EPC of C. Think an in depth survey will be well worth the investment before I make this sort of investment. My concerns are real cost of ownership including servicing costs, will it really warm my home at an affordable cost. Don’t know what cost electricity will be in the longer term. Think governments have more work to do. Great vid thank you. Mike
Well the efficiency c
Is dependent on the flow temperature. The lower that is the better the efficiency. You could already Start to tun the heating curve of your current system to the minimal flow temperature necessary to heat up the building. That saves you gas. The added benefit is that if you get it below 55°C you can expect a heat pump to work reasonably efficiently. Adding insulation will bring down the required energy. But that's true for any heating system and not directly related to heatpumps. As long as flow speed and heating surface allow running at or below 55 heat pumps work. That's true regardless of the insulation.
I you use only 1-zone, what would be your preferred way to setup a smaller room like a bathroom where you also would want a higher temperature? I opted to lay the piping at 5cm from each other but I think it still isn't enough. Would you opt for a extra radiator calculated on the same water temperature?
Maybe an idea for a future video. If you don't have enough surface erea to lay floorheating. Thanks!
It depends on your heat loss. If you increase the flow rate to bathroom you can relatively easily raise the temp
this is great and exactly what would need to happen in british columbia. matt risingers videos are similar too. who designed this london house? it's brillinat
Great video, as always. Interested to know your advice on what you fit to external unit. do you fit isolator ball valve first, then the antifreeze drains, or the other way round; do you fit drains on both F & R, i've seen some with only 1 fitted, there risk there must be water caught in the line that has no drain?
I don’t fit anything outside apart for a single AFV
@@UrbanPlumbers Excellent
Hello, I hope things are going well
What are the benefits of humpbacked speech?
Thank you
So from your videos, it's seems that when you switch to ASHP, you only have one room state and UFH with no actuators.
Any reason why you don't now require automatic bypass valves on the Y plan? Was under impression it's usuful unless you use towel radiators and before any zone valves
Great video. Do you not need secondary pumps for the two circuits or is the ASHP pump powerful enough to cope?
You shouldn’t use circulators on manifolds or low temp setups. If you have too much system resistance to run ufh then you may need a buffer
@ASHPowner Would you say all the cost associated with insulating the house and the heat exchanger system are worth the effort?
Are you expecting a break even, if so how long, and if not what was your reasons for insulating so well?
Do you need to consider only heat losses when choosing a heat pump? Will there always be sufficient heat for the hot water, if the pump is sufficient for heating?
Hi Simon
I know you are really good with vaillant controls, can I use vrc720/2
With underfloor heating zone, plus two heating zones and DHW cylinder or I need some additional controls?
Thanks
Vr71 needed plus 2 x VR92, unless you want to run on pure WC - then just VR71 plus VRC720
two questions
If the cylinder is calling for heat is there still enough flow rate through the heat pump?
If you have south facing rooms with lots of glass how is the underfloor heating controlled? It seems to me that they would overheat. Similarly a lot of people would find 18C too hot to sleep in. I try to avoid UFH running under beds because they act like thermal stores, nice when you get in but not at three in the morning when you wake up sweating.
I have been through the scenario of overheating or under heating on my systems already ( no zoning ) - and every single system was fully adjustable on flow rates alone - however it needs to be designed well for this to be possible.
On the question of solar gain - it has never been a problem as well - but if it ever becomes a problem, you can always add a couple of actuators and wireless high temp limiters for any areas. I haven’t had that issue yet and I have fitted a lot of those set ups now.
DHW - yes we still have good flow rate here. DHW circuit will always be lower resistance to your index heating circuit - so that is never an issue, unless you install a wrong cylinder with restrictive coil.
Does it matter where you place the Y filter on the return? i.e. can it be placed between 2 manifolds.
Is the slab fully insulated underneath?
I looked at using those 20mm eps panels for a ufh but tue heat loss into my unisulated slab was slmething like 900w per hour! Just waste - so ive gone with just insulating my flor with 20mm eps and using hydronic fan convectors which also work well at low temperatures.
Downward heat loss isn’t that much apparently - 10-15%. This house has minimal insulation of only 20mm.
I am not doing any insulation to my house slab.
That looks very nice.
I was a bit surprised by the large spacing in the UFH. Is there still enough capacity to use a bedroom as an office with a 20 degree temperature by adjusting the flow rate or is it pretty much limited by design?
I wonder if overdoing it with the UFH would hurt the efficiency. For example, what would happen to the COP and load on the heat pump if you put 10 cm spaced UFH everywhere? I imagine it would take more time to put in and cost a bit more, but is there such a thing as too much UFH for a heat pump?
Yes, you can easily adjust flow rates on this system to change the room temp by +/- 3c
Nice work, I was going to say it could cause problems down the line if only 17 degrees was achievable in the bedrooms.
@@UrbanPlumbers
@gunsey876 22c easily achievable if you want to
You have designed the heat loss at worst case external temperature, so if there is no system temperature controls then when it’s 10 degrees outside the rooms will be emitting more heat than is required, would this lead to slightly warmer rooms than the design temperature when it’s 10 degrees outside, or do you have weather comp installed?
Great video. Looking to do similar deep retrofit to our house next year in SE London and put it on Open Energy Monitor - would love to get you to install it if you're interested?
Email me please
Brilliant! So would you zone it if upstairs was radiators?
No
@UrbanPlumbers so the ashp runs constantly all day and night or has the vaillaint controls got something that controls it ?
Very interested about the open loop approach. Where to you position the thermostats?
Most systems we install are run on pure weather compensation and don’t use thermostats or internal room infuence
Very clever soul you are , you did mention a few weeks back when I said about a lot of your videos are in regards to big houses, I did mention I live in a small three bedroom house and it would be nice to see a video on one of these houses, your response was that you are planning to do a video on your house with installation of a heat pump , is that still going to happen? As yet not found one of your videos which has not impressed me with your explanations = wow.
Yes my house vid is happening over Christmas period.
@@UrbanPlumbers looks like you’ve been good this year and not naughty, present from Father Christmas.
In London is it easier/harder to work in flats or houses ?
Did this project have any other videos on the other eco improvements like the air sealing, mvhr?
Client here. No, we haven't shot any other videos. But Szymon has shown you all the cool stuff already.
Great video again Do you advise vaillant? as it’s not the first one you fit and why ? Thanks
Yes, great units, acceptable controls and a decent company
thanks I am moving my business to renewable but there is a lot to take in as well as getting the right knowledge and doing a perfect install , I need to think about , is my tiny company big enough to install heat pump? what product /company to use and backup you are getting , how do you price a heat pump job ? thanks again @@UrbanPlumbers
Thanks
Thank you 🙏
Hi simon, like the install, nice and neat, however i don't agree with running open loop systems, it depends on the property of course but i find that zoning by room is beneficial. Open loop ignores solar gain and internal appliance gains eg an oven or computer, therefore you would be over heating some rooms whilst others arent yet at temperature, when shutting off the zones that have met their set point would allow the heat pymp to modulate down. What do you think of this?
You can still run open loop with stats that will close overheating zones. What you don’t want to do it to allow a small zone to turn the heat pump on, on its own
@@UrbanPlumbers interesting, can I ask what your opinion is on blending valves, I see the industry using these alot for 2 zone 2 temp with rads and underfloor, once again I don't really see the point for this because you're creating let's say 40°c for the rad circuit only to blend it down to let say 30/35°c for the ufh, would you just run it all at a single temp allowing the underfloor to heat up and satisfy the call for heat faster rather than wasting the heat that's already been created
Most heat pumps, like the Aerotherm you can place the controller which senses temperature in the room with the highest solar gains and enable internal influence to adjuist the compensated flow temperature down. System volume is king with any vapor compression system. For very large properties, HMO's, student accomodation, hotels etc.... zoning is stil required.
I agree with Simon but I also agree with you :) It really has some up- and downsides from my point of view. And as you said it depends on the knowledge about the usage and all the non usual ocasions like having a party with 20 people in one room, a wife which gives Yoga lessons in one room, an power hungry heat emmitting gaming PC :)... and so on.
But I of course highly cheer the knowledge, skill and pride Simon is putting into calculation of all the rather static energy needs of every single room and doing everyithing right from planning to delivering the project. I really learn a lot even if I'm not from the feeld directly!
I have optimized now 2 airsource heatpumps and one water-water heatpump by between 30 to 50 percent year to year energy consumption. They have all been put in without proper planning and just left with mostly standard settings or much to high preflow temperatures and many other misconfigurations on other settings. To me it seams that you really can screw up a lot and it does not really matter what kind of heatpump is installed.
Very well presented as usual.
Just a brief question concerning flow rates...is there any harm in having a higher flow rate? Let's say my house "needs" 800l/h but the pump can easily provide 1100l/h. Will upping it to that level have any detrimental effect apart from adding a few Watts of energy useage?
More energy used on the circulator resulting in lower overall efficiency, although mean water temp is higher so flow temp can be lower which may balance out higher pumping power
@@UrbanPlumbers
Thanks. So as long as the additional energy use is minimal, there should be no harm done I guess...👍
Yes, shouldn’t make a dramatic difference. No harm on slowing the pump down, but I would try to lower the flow rate by throttling the system
Because the system is designed for certain temperatures in each room are you able to boost the temperatures at all for special events etc? Also what if I move into a house where it's set to 21 but I prefer 19, what do I do?
Yes you can a change the overall temperature and adjust individual room by changing the flow rate on the manifolds.
The fact that it’s designed to 18/21 doesn’t reman that you can’t run it lower or higher
Type of 3 port valve used?
Could you use 28mm PEX or similar instead of copper as the temperatures are so low? - about a third of the price.
Pex needs to be a size up so 32mm Pex for 28mm copper.
Hi Simon Great video. I was just wondering about the flow rates. Doesn’t the aerotherm run automatically at around 850lh? But your design speed is 650lh? So it will be going too fast to achieve dt5? Would you manually reduce the pump speed to achieve the correct DT or is the auto speed and a smaller DT acceptable?
Thanks
Matt
Arotherms are targeting the flow rate most of the time and narrower DT will happen in warmer months - it acceptable. Even when it tries to slow the pump down it may not be able to slow enough for DT5 on a well designed system - that’s totally fine
@@UrbanPlumbers thanks for the quick reply!! Just built my own house and have installed the system myself with a lot of inspiration from yourself and heat geek. I noticed that with my flow and return temps were more like 3 and I was wondering if it could be an issue. My system is running at 0.25 heat curve and heating the house perfectly 💪🏼
Thanks again
Matt
Yes low heat loss and very flow temp will run and small dt most of they year
For hot water, does it use the heat pump’s 37c flow to heat up mains water temp and then an electric element to top it up to 60c+?
No, it’s a R290 unit that can go up to 70c if needed
I was looking to see if anyone asked this and you have. Thank you.
And thank you Scymon for taking the time to answer.
did you say that the 3 way motor valve only does either heating or hot water, if so when is hot warer srored
When the hot water cylinder calls for heat.
Can you run a system that has been zoned with actuators and TRVs as an open loop system?
Yes - just remove actuators
Does the outside temperature effect the efficiency of the heat pump? What COP would you achieve with say an outside temp of -2 degrees?
Of course it does. This system was showing a cop of 3.0 with around those temps outside. You would generally expect around 2.7 with -2 and 35c flow temp if I remember the figures correctly
At that heat loss is UFH worth the costs and complication?? Constant heating at 21 deg everything ends up at the same temps pretty much.
We don't need UFH for the heat output. But should we live with radiators all over our walls, like animals?
Are the heat loss calculations really accurate or do you run the system over time and then adjust for heat loss errors?
The calculations are surprisingly accurate. Assumed air changes aren’t. It is best to do calculations but measure the air changes with a blower test.
I need your advise. Im buying a 1950/1960 semi detached house with an extension. There's is no fill in cavity in the origional part and only 50mm cavity with 50mm insulation in the extension. Can this house ever be made to have a low heat loss? Apart from cavity fill, what else can be done? What's would you estimate it's heat loss to be its 130sqm
Get a full heat loss survey done by a reputable company. Cavities can be injected, loft can be insulated and windows can be upgraded. Should be possible to drop heat loss to around 5-7kw if there are cavities there already.
Client for this project here. Yes, you can bring a 1960s house to the very highest standard of efficiency. But we have had to look at almost every element of the construction. It has all taken a lot of work - you need to find motivated and expert professionals who will pay tremendous attention to detail. Like Szymon!
won’t the flow rate be the same through all loops? are you controlling the temps by the size of the loop? eg wider centres in bedrooms = lower emittance = lower temp than other rooms? What if later in use the client wants to adjust relative temperatures?
Flow is different for all the loops depending on:
1. Room heat loss
2. Pipe spacing
3. Desired temperature
4. Floor coverings
@@UrbanPlumbers so that can be controlled at design stage? Are there issues with lower flows in some loops (or doesn’t matter as they’re parallel)? but if the customer decides later they’d prefer the bedroom a little cooler in the evening do they only have the global control? I do like the idea of using the circuit itself as the buffer for defrost - that seems very smart design and simplifies too
You can adjust the flow rate per circuit at the manifold. The red/clear things on the upper manifold are flow rate meters and adjusters in one.
Does anyone know whether there are smart zoning valves that communicate with the heatpump? In theory, that should allow for zoning while still ensuring the minimal flow speed required by the heat pump.
You shouldn’t use smart valves that can fire the heat pump - flow is not everything, fully open system will usually be more efficient and cheaper to run than zoning. Zoning is not needed on weather compensated seat ups anyway. The only way to use smart or regular radiators valves is to prevent overheating, which again shouldn’t be needed on a correctly designed system.
@UrbanPlumbers I get that a fully open system will always be more efficient. But there must be scenarios in which the worse efficiency is made up by lowering the total energy required. For example one or two people live in a large house with high amount of heatloss. So cases where most of the rooms might not be used. But there are also two other somewhat stupid reasons. The first one being that customers want them (even if they're not good for them. And the second one being regulations. German efficiency regulations (that probably weren't designed for hear pumps) require you to have zoning if you want any grants. So in germany, basically, any installation will have them... and/or a buffer and a flow over valve.
Can we talk about the hydraulic separator and its calculations?
Do the UFH manifolds not need circulation pumps?
No. Heat pumps have bigger pumps than on boilers and because radiators in properly specified systems are sized to run at the same temperature as the UFH, you don't need to blend either to keep the temperature down.
Quality install… with all this insulation and heat recovery, how do they keep cool in the summer?
They don’t 😂😂
Keeping cool is a big problem in modern houses.
@@deanchapple1 so they install AC units cause… saving energy!
@@alimack5489 AC units are expensive unless of course they have solar PV.
Perfect combination, Solar PV and AC.
@@deanchapple1 AC isn't that expensive to run tbh, especially if you're clever with curtains and windows. Mine were using maybe 300W to cool two bedrooms when it was 30 degrees outside.
Insulation also keeps heat out and you can add a cooling option to this heat pump if you only use UFH. It's limited compared to a full AC system, but may just be enough.
Out of curiosity - in colder climates (e.g. eastern europe, northern europe) where -20C is relatively common during the winter, how much power would be used for defrosting?
P.S. Always informative and interesting, keep up the videos!
Guess answer based on physics alone:
Most of the energy in defrosting is changing the ice back to liquid, so temperature has some effect, but not a massive one. I would guess you recover some of the heat added to the evaporator metal when it switches back to heating mode and takes heat back out again, but presumably the fan throws most of it away.
@@bringiton8989I heard humidity and precipitation are the biggest influence on the frequency of defrost cycles
@@chrisE815 yes, this is true. I was just thinking "energy per defrost cycle" but you're right. Air at - 20C is so low in humidity that fewer defrosts should be needed.
@@bringiton8989 Cool, thanks for that! I assumed from the bat that it would be way more. its good to know thats not the case really.
If there are no thermostats in a room how do you manage a sunny day vs a cloudy day? Would a room overheat?
It shouldn't. I would expect that the flow temperrature is set by weather compensation, so it will reduce on warmer days. Also, the heat pump is also trying to maintain a DT of 5C, so if the return is coming back with less than this difference, the heat pump knows that some of the rooms are getting more warmth from somewhere else, and again the heat pump can either modulate down, or switch off if it has reached the limit of how low it can go.
@@tlangdon12 Some rooms can be south facing and be warmed by the sun, and north facing ones would get no benefit from the sun, so they can't all be treated the same. Just seems to me thermostats make everything simpler.
Buffers are useful for energy storage too.
If you are running a heat pump with PV cells, for example, you can use the excess electric power to heat the buffer, so that you don't have to run the heat pump the whole night, when, due to lower temperature outside, it will be less efficient.
Also, you can use solar energy to heat the buffer during the day.
Remember that you have a lower set back temperature at night so that helps with heat pump efficiency.
Gains of having a buffer with solar may be quickly negated by lower overall system efficiency of having a buffer (mixing) and running another circulator.
@@UrbanPlumbers Well, you can run the space at 18 °C at night ( lower than that, and there is risk for mold growth, if I remember correctly ).
Keep in mind that I don't consider it necessary for heat pump installs, too. ( Mechanical Engineer by trade ).
HVAC installs differ in every site and budget, and what is optimal on one occasion, is suboptimal in another. And that is why thoroughcalculations are necessary, and rules of thumb ( "so much square meters, you need so much KWs" ) are A VERY ROUGH, VERY-VERY ROUGH, estimate.
Buffer is too expensive for thermal storage only, as it has very small capacity compared to building fabric and will lower COP of system both during normal use but also very much more when boosting for storage
Simply raise flow temp so that room temp changes 0,5-1 degrees. That is perfect energy buffer with way more capacity and is totally free.
In a house like this, it will take quite a while until you loose heat. So you can simply set the target temperature one degree higher when the sun is out. Doing this, you can store a lot of energy in the house itself.
@@Felix-st2ue If your insulation is on the inside of the mass like this one then you're not really holding much energy in the house. If you've got an old stone property and you're able to insulate outside it, you're able to store a lot of heat in the mass of the walls.
I see a lot of copper. I have a quote from my installer that uses steel pipe. What is the advantage or disadvantage of using galvanized steel piping?
Time to thread the joints v pressing
@@plumberdan5720 is that really the only reason? What about condensation? I guess copper condensates just like Steel? When cooling does this give problems with steel?
Not unless you fit a homonulus valve
Can I ask why you choose that capacity if heat pump for the property rather than a 5kw one?
This is a 5kw heat pump
If the heat loss was 3.5kw - why didn't you use the 3.5kw vailent? Which can do 4kw according to the sata sheet. Thanks.
@TC-V8 because 3.5kw unit is the same as 5kw and minimum modulation is also the same. 3.5kw is just a 5kw unit with capped top output
Bit of a n00b question: does this setup mean that the tank also accumulates and stores water at 35C? Also, considering potential compatibility with Sunamp: does their requirement for 45..55C inbound mean that I'd need to run the heatpump also at 45..55 in?
Client here. The hot water tank is set to 50 degrees, with a weekly anti-Legionnaires cycle to 60. It's easy to run your shower too hot.
@@ASHPowner thanks!
I've always been curious what happens to the flow temperature in such a system when there is a DHW cylinder that needs heating to 48-55C. If the flow temperature is increased when there is DHW demand, doesn't this run the risk of overheating the floors if they are also getting water at 48-55C? I'm guessing that the heat pump sees the returning water is above the set point for the flow temperature for heating, and so runs the pump but doesn't run the outdoor unit to add any further heat to the water. In this 'mode' there is not enough heat stored in the system water that was circulating around the DWH loop to raise the temperature of the floors more than a few degrees above where they were, so no danger of overheating?
The floors are not getting water at high temperatures, there’s a diverting valve.
@@Etacovda63 When that diverting valve switches back to heating they certainly are.
@@tlangdon12 yes, and at the absolute most, its primary and return that holds that temperature, 30m of 28mm piping.
Assuming thats ID, thats 9L of water, going from 55 down to 35 degrees.
Thats less than 250w of power, distributed across an entire house.
The heatpump doesn't even need to account for it, thats what the valves for - the heatpump goes back down to 35 degrees and it literally stablises back to normal in seconds. If I could be bothered doing the maths, Id say the water wouldnt even complete a circuit of the floor before being back to normal.
Czesc, w Polsce licza heat lost tak samo?
Tak, tylko DOT jest podzielone na 4 strefy od -16 do Chyba -20
Ok great vid, but question, the 18C and 21C internally is based on an outside temperature of “What” exactly. Surely as the ambient temperature falls the efficiency of the system falls, added to that you have “ defrost cycles “ the colder it gets the more time in defrost, right? So what’s the starting point. Back in the day we used to assume an ambient temperature of -1C with a flow temperature of 82C to maintain an internal temperature temperature of 21C, now I know that’s not done now but what is the starting point. I’m thinking if the design is based on -1C it will struggle at say -5C or am I talking rubbish.
-2 at 21c inside is the heat loss calculations based on. Here it’s 3.5kw. SCOP (Seasonal Coefficient of Performance is based on average of 12 months) and is expected to be 4.5-5.0 here.
The design flow temp at -2 is below 35c here and at those conditions the COP (not seasonal - actual efficiency) is expected to be around 3.0
Defrost show a dip in performance and efficiency, however the dip only happens between 1c and -3c - due to high humidity of air
Once the temperature drops below -3 the unit recovers as the air is much less humid so there is much less defrosts happening
At -2 this unit was defrosting 1 per around 45-50 minutes
OK that makes sense, well good luck in your endeavours, your pipework is second to none.
How do you change individual room temperature if someone want higher or lower temperature?
Change the flow rate at the manifold
Adjust flow rate. Different temperatures are so overrated and not needed 😉
I think the lack of control seems counter intuitive to many because having stats everywhere has been hammered into everyone for so long - similarly with ‘smart’ thermostats and letting people believe they are in “control”
@@UrbanPlumbers Are you married ? 😃
@@eliotmansfield happily
Where is the PRV internally?? Are you just reliant on the PRV at the heat pump??
Yes, unit only. Why would you want 2 prvs?
So you have to heat the entire house no matter how many rooms are used? In paper the system may be running super efficiently, but if you are heating areas which are not used then you are wasting energy no matter what?
As counterintuitive as it may sound - heating half the house will very often result in much more cycling, higher flow temperatures required and also also comparable or higher energy use not lower! Hard to explain it in a comment - I will shot a video about or check heat geek video about why not to zone.
If the UFH is fully open circuit without any thermostatic controls for any rooms.
How do you get round building regulations Part L where it’s says individual thermostatic room controls are required in certain rooms such as bedrooms?
It doesn’t require that on fully weather compensated set ups
@@UrbanPlumbers i see, how do you get round lowering a bedroom temperature to say 18oc for say sleeping comfortability when the main room stat is designed and calling for 21oc would you have to lower the 21oc to 18 everywhere?
@@UrbanPlumbers I was trying to interpret the Part L differently after you said you don’t need room thermostatic controls with weather comp. But I can only find this about thermostatic controls in part L regs:
“Thermostatic room controls 5.20 For heating systems in new dwellings, or when a heat generator such as a boiler is replaced in an existing dwelling, each room should be provided with thermostatic room controls. These should be capable of being used to separately adapt the heating output in each room served by the heating appliance.”
They don’t mention any exceptions with this that allows no controls with weather comp or ashp. So I would suspect you at least need room thermostats in a bedroom etc.
I’m curious where you see the regs differently, am I missing something?
Thanks
@@UrbanPlumbers apologies for the pestering. I can’t for the love of me find in part L where it may suggest no room thermostatic controls are required with WC.
Could you elaborate on this at all, as it would suggest you would still need a thermostat in a bedroom no?
Client here. In practice building control made no objections at all. The draft future part L suggests 10W/m2 (i.e.,Passivhaus) as a bound below which room controls might be technically infeasible, but there's no hard limit.
Interesting. We're currently planning for something similar when we extended and renovate our bungalow in a year or two.
Do you do requests? Can you do a follow up video because it would be interesting to see what scop it achieves in a years time.
Client here. We're not expecting a great overall COP, because the space heat demand is so low that our hot water use will dominate.
In the first few days of use we got worse COP than expected for the cold weather. The floor slab was completely cold and the UFH return will have had a high Δt, even with a low flow temperature.
👍
Tidy work
Isn't it that 1kWh of electricity could move up to 5kWh of heat in to the property (hence 500% efficient)? The 1kWh of electricity doesn't produce heat in and of itself, it just drives the pump that moves the heat?
Actually that 1kWh of electricity also contributes to heating!