Chinese Diesel Air Heaters - Part 8 - Exhaust and Mufflers
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- čas přidán 3. 07. 2024
- These Diesel Air Heaters run very clean with NO smoke and very little smell - IF they are Installed correctly, and Operated correctly and Maintained correctly.
The exhaust system of these heaters should be kept as short as possible, and with a minimum of bends, restrictions and back pressure complications.
The intake air and the exhaust outlet flow is produced by a small combustion fan running at a speed of around 4,000 rpm, a far cry to the 200,000 rpm plus speed of an average motor vehicle turbo charger. In addition these heaters lack the induction and exhaust capability of positive displacement pistons.
The exhaust outlet should ideally gently slope downwards and the outlet should be opposite to direction of travel so as not to produce a back pressure component.
Any exhaust low spot must have a drain hole to allow removal of condensation or un-burnt diesel to escape. Mufflers must be mounted with their drain hole on the bottom, or on a down facing slope so they can drain.
A flow through muffler not only creates less restriction in the exhaust system but is also 1dB to 2dB quieter than a baffled muffler. Two flow through mufflers produce a whopping 10 dB of noise reduction. The dB scale is a log scale, so 10 dB change is a 100% change.
Here is a link to a flow through muffler to get you started in your search.
www.ebay.com.au/itm/Air-Filte...
Disclaimer. As is normal, this is information I have gained from written manuals, years of experience, and my own testing. You must do your own research to see if my suggestions or opinions are right for you and your own particular circumstances. J - Auta a dopravní prostředky
Just started looking into diesel heaters and really enjoying your very helpful videos. Thanks very much. Would never have expected the flow through was quieter so you've really taught me something very useful.
I have watched a ton of diesel heater videos while doing my research. That's what I want to do: install, operate and maintain correctly from the start. Your videos are the best. Thank you very much for sharing your experience.
This is the best explanation of diesel heaters, thanks
Thank you John, this was a real eye opener on muffler design. Thanks for posting.
Your welcome Buzz, glad to be of some help. JMcK
Bloody fantastic work John, thanks for your efforts mate.
Pleased you liked them Ash. JMcK
You probably wouldn't believe how useful your tips are... THANK YOU.
Thanks for the positive feedback Alexandre. JMcK
Best video on these mufflers I’ve Found , Thanks 🙏 ps I love all your records and time you put in
Thanks for the positive feedback Drone Pilot. JMcK
@@johnmck1147 link to the flow tru ?
That is incredibly useful information. I believe my muffler is a flow through so I think I will get an additional one to reduce the noise a bit more. Thanks for making this video.
Your welcome Mange. JMcK
Not only a 10dB drop, but also eliminates certain higher frequencies which make it appear exponentially louder. Very good video.
Thanks for the video John.
You answered all my questions about the mufflers.
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excellent controlled environment and explanations with various samples, thank you
Pleased you enjoyed it DA. JMcK
very very helpful i installed my heater about a month ago so now im going to add another muffler and then work on getting the pump quieter thank you John top video.
Pleased it was of some help Ross
Awesome tests mate.
Really enjoyed watching this and it helped me a lot.
Cheers.
Pleased the series was of some help. JMcK
Appreciate all the in depth analysis. thanks.
Pleased to be of some help. JMcK
Excellent video amen.
Great detail, comparisons and clinical testing. Thanks...
Thanks James. JMcK
Watched this video last week and thought i'd give the twin exhaust muffler idea a try. Definitely quieter,significantly less roar. Thanks for the tip John.
👍
Really Grateful for this info as I’ve just bought one of these heaters for my MH.
Thank you also for the use of Kerosene advise, you’ve explained both so very Clearly and I feel a lot more Confident in its use.
Keep up the Good Work. 👍🏻
Thanks for the positive feedback Anthony. Glad the videos were of some help. JMcK
thank you for your research here, that was super valuable to me. i bought a kit with 1 muffler, already have the 2nd on the way before its even installed as i know i want it to be as stealth (aka quiet) as possible.
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Thanks Again John . Very Informative.
Best diesel heater exhaust review by far
Thank you U38 for those positive comments. JMcK
Wow John, you certainly know your stuff, very informative and useful information, thank you very much.
Pleased you liked it Brad. JMcK
Thank you for the video, from Henrico County Virginia
Your welcome Norm. Pleased you found the video helpful. JMcK
Glad I found your video before I purchased! Thank you
Hi IB, pleased you found it helpful. JMcK
Another outstanding video, thank you for sharing your test results.✌️
Your welcome Eric. Glad they were helpful to you. JMcK
@@johnmck1147 ✌️
Love the videos John , thanks for all your efforts, you are the guru. I plan to put my exhaust directly into the 4' exhaust of my main engine which I think means I can do away with the muffler all together . As the main is down below and sealed from the berths and the saloon , very little noise will penetrate any way.
Hi Bradley, thanks for the feedback.
Sounds like you have a plan. I would be concerned about engine exhaust coming back up through the heater, but I can't make any comment as I have never tried that myself. Suggest you bring heater exhaust in at sharp angle to lessen chance of back flow into the heater, and have a CO tester available.
I would be interested to know if your plan works. JMcK
Excellent. Thank you for sharing. The info on exhaust restrictions was particularly useful to understand. I had been planning to try adding some form of baffle insert or wire wool into the straight through muffler.
Hi J258, Suggest don't do it. The tiny exhaust does not do restrictions. JMcK
@@johnmck1147
Thanks for this info 😅
Thanks buddy. You're helping me a lot.
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Thanks John .. excellent video !!
Glad you liked it, and hope it was helpful. JMcK
Fantastic video. Thanks for the detail!!!! (And all the hard work!!!)
Thank you for the positive feedback BA. JMcK
Thanks for taking the time to do this, I would guess the motorcycle muffler has a larger inside diameter so the exhaust isn't forced into the baffles, would be interesting to put some rifling on the entrance to the muffler, get the exhaust spinning and maybe it would enter the baffles more. Great info, just got mine so time to experiment and fall Salmon season gets cold in the boat.
Thanks for the feedback Steve. Keep warm catching those fish. JMcK
Great information, done properly. thank you so much for this
Thank you. JMcK
I'm so glad to have come across this series of videos - a definitive guide that has been most helpful.
It'd be nice if there was a way to capture the exhaust waste heat without compromising performance.
Hi Michael, thank you for the positive feedback.
Yes, you can capture some of the exhaust heat, and I may possible do a video on this at some time in the future. You use a 32 mm copper exhaust pipe that is wrapped with 9 mm copper pipe and a water circulating system. You need to use copper to get the heat transfer.
@@johnmck1147 Thanks for your reply, John.
Capturing waste heat is interesting to think about. I thought of air-to-water heat exchanger too but it'll require a water pump unless there was some clever way to make a thermal siphon - maybe some sort of DIY heat pipe might work.
It's also interesting that the Chinese cloned the air heater but not the equivalent diesel water (engine block) heater.
@@MichaelAChang eBay HAS had Chinese versions that do BOTH air , plus an exchanger section to plumb to the engine block as well.
I went with the double muffler that you did a sound demo on and the difference is amazing, I had one muffler to start with but when i added the second i noticed a big difference and much more quieter. Brilliant video john great information. The mufflers i purchased are the straight through type not the type with the bend.
how did you connect the two mufflers?
@@dansmith6990 i used the exhaust pipe, i used a hacksaw andcut a 3 inch piece then used jubilee clips.,Use the smooth bit of the exhaust part, i bought a length of ebay, its cheap.
Very good, thanks for info.
answered a question from an earlier video thanks
Great video. Thanks mate
Thanks Luis
Thanks for Perfect work's🙏😎
Your welcome. JMcK
Thank you for all the info. appreciated
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Cracking informative video, thank you.
Thanks David. JMcK
Thanks for the video!!
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I have been fitting one of these heaters during the last week and worked perfectly, when I got the required but and bolt to fit the muffler I went under van and did the last bit then went inside put my feet up ready for a final check,all seemed fine then things changed and up comes error 8, having tried a couple more times it seems the muffler was the last straw, too many angles it seems , your video is a great help so thank you very much.
Thanks for the feedback Rachel.
really good review thanks just what i was looking for 👍👍👍👍👍👍👍👍👍👍👌
Your most welcome Bright Eyes. JMcK
Wow so helpful thanks so much 😁
Your welcome Jesse. JMcK
Great stuff John! And very interesting, data-based results for the straight-through muffler. Something else to consider is that convoluted pipe causes it's own restrictions to flow, particularly at higher flow rates. So using smooth-walled intake and exhaust piping wherever possible is a good idea.
I agree Michelle.
Unlike internal combustion engine exhausts, with positive pressure exhaust displacement, these little heaters only have a very small plastic fan to push out the exhaust, so they don’t like any restrictions in exhaust. JMcK
Well done. Thanks.
Hi Doug, pleased you found the videos helpful. JMcK
Thanks, something I didn't know.
Thank you, sir.
Hi, I also would love to know that answer. I suspect a number of factories, or a number of assemblers. The burner castings all look the same, but the heaters will come with different quality gaskets, some have different ECU's, and I have seen some with a coloured case to have a bad moulding that causes the fan to scrape on the case. However the big difference is in the accessories and type of controller supplied. Suggest you buy from supplier with good ratings and one who has returns and ideally a local warehouse. J
Thank you heaps helpful
Thanks Phil, glad you liked it. JMcK
Good engineering.
Thank you. JMcK
John does a great job on his videos, however when the dosing pump is installed correctly, and the system has been bled properly, the will be NO air bubbles in the system. I like to take the line end that connects to the heater and put it into fuel so it is covered, go through as many bleed cycles needed to remove all air, then connect to heater. It will start burning fuel very quickly, with NO flooding.
Thanks great info and great work :)
Thank you. JMcK
Your videos are so in-depth and fascinating, that I couldn't help myself watching your playlist 3 times already!
I wish you had the same on the new water heater Chinese clones of Webasto or Eberspacher water heaters.
It would make a great floor heating for a tiny house, RV or a cabin.
I don't know of a cheaper way to heat a small space, short of cutting and splitting firewood to use in a stove, for free!
Here in Ontario Canada, Propane is $20 for a 20 lbs bottle refill at Costco and contains 4.7 Gallons (3.8 L) LP. Makes Propane a little over $1/liter. Diesel is about CAD $2/liter and has more than 1.5 times the energy. 138,490 Btu/gal compared to 91,420 Btu/gal of Propane.
If you know a cheaper way to heat, please comment.
Useful, thanks!👍
Pleased you found it helpful. JMcK
Hi Michael, I know of no high altitude kit that is made or sold for these Chinese Diesel Air heaters. These heaters will not suddenly stop working when used at high altitude but they will run rich due to lower levels of oxygen in the air. This will cause excessive carbon buildup in the heaters. Without an altitude kit, I would try running a kerosene/diesel mix 50:50 or up to 80:20 to lessen the carbon buildup. Kerosene is a very clean running fuel.
As for spare parts, I suggest you carry some glow plug atomising screens, make yourself a glow plug spanner, and get an 8mm coach bolt to aid in screen removal. If you are careful with removal glow plugs last a long time and are easily cleaned, so a spare is not normally required. The real risk is breaking one on removal to replace the screen. You will also need to make a small wire pick to clean carbon out of the glow stare air hole, and a spare fuel filter is handy. If you intend to open the heater you will need a gasket kit as they are sometimes destroyed on opening if the heater is well used.
A lot of kits come with an "air intake silencer". These are not an air filter and they don't work well as a silencer. I throw them away. You will need a combustion intake air filter, and if it does not come in the kit, you can buy them cheaply on line.
Set up correctly, these heaters run very well and very clean using correct fuel. The main maintenance issues are carbon buildup in the atomising screen and a blocked fuel filter. J
Are there alternate metering pumps available with lower stroke volume, so you could swap out to get a lower flow rate at a higher altitude?
Fantastic
Pleased you liked it Patrick. JMcK
Thank you so much :)
Pleased you liked the video Rod. JMcK
Normally if the fuel hose is tied back away from the exhaust this is not an issue.
But exhaust wrap is always a good idea. JMcK
You can use more than one muffler, provided it is the straight flow through type. However there is little benefit in having more than one muffler. Most noise comes from the fan running at a high setting. JMcK
Lover your video. You should be hired and paid big $$$ by manufacturer.
Thanks for the positive feedback Matt. JMcK
Thanks for all help on other topics regarding the heaters. I'm going to install a diesel heater in my shop. I've seen videos where they recommend the combustion exhaust pipe be installed in a downward direction so that any condensate or extraneous diesel fuel will exit thru the muffler. My original plan was to have the combustion exhaust exit above the heater. Now I'm not sure that's a good idea. I'd appreciate your perspective.
Hi J,
Combustion exhaust is an expanding hot gas and it likes to go UPWARDS. Long downward exhaust slope creates restrictions in the combustion process. In many motorhome and caravan installs the exhaust is generally horizontal or slightly downwards. If there is a low spot in the exhaust you need to drill a small hole to act as a condensate drain. Outside the vehicle this drain is no problem.
Inside your shop it is fine to run the exhaust above the heater, but you will need a condensate drain at the bottom. If this drain is inside your shop you will need a water trap drain to prevent escape of CO gases.
Have a look at the boat video in this series. Most boats have the exhaust exiting far higher than the heater, and they have a water trap condensate drain at the lowest point.
Good luck. JMcK
@@johnmck1147 Thanks again!
John, thank You for all this information.
I'm installing a 2kW unit into my van and carefully following all Your instructions.
But few things about the exhaust piping.
In my opinion the original china pipe is crap: sleek ends but heavy corrugation in the middle, no way to cut it to proper length. And it is so stiff any force applied at muffler will punish the hose clamp at heater.
So, replacing it with real bendpipe, but be careful: the German ancestors could not agree the caliper. Webasto uses 22mm and Eberspacher 24mm (inner dia). Chinaheat is a copy of E, I guess, so correct hose dia is 24mm. I learned this the hard way!
Thank You!
Edit:
Just installed the new exhaust and noticed the alu-paper intake hose had taken some hit as well, BUT: intake is 25mm !!
So there are 3 dimensions related to heaters: 22,24,25. Wunderbar!
Hi Hiki Tech,
Thanks for the feedback. Yes, it would be nice if the manufactures could agree on a common standard. JMcK
@@johnmck1147 Yep, all we can do is just talk about it!
Another thing: Did You address the air-to-fuel ratio tuning in any of Your videos?
I have the yellow SmartSensor CO meter (product placement in Your vid :-) and I measured CO at tail pipe: 10ppm (=next to nothing) at low Hz but goes up quickly when fuel feed is increased. Rich mixture, is this indicating too low fan speed at hi power?
Could this be tuned with (RPMmin-RPMmax)/(Hzmin-Hzmax) -linear function?
@@hikitech218
Hi HT,
If you like experimenting, yes you can play with the fuel air mixture ratios, but this is not for the average owner. You can get into a lot of trouble.
Suggest you do same test on your motor vehicle and note the results results. You will find them interesting. Suggest you do not start playing with mixture ratios on car as again you can cause more problems than you wanted. If you want to do this, suggest you use wife's car. - joke.
JMcK
@@johnmck1147 Unwritten rules:
If it works, don't touch it!
If You want to play with techno-gadgets, leave Your wife's car alone!
I have seen comments that the controllers and heaters are not correctly paired when they are shipped: 5kW parameters in 2 kW heater.
But I agree it is sensitive area, and requires gas temp meas, Co meter and actually a lambda sensor.
If I get my hands on some of those meters, I will do some tetsing, anyhow it is all digital parameters which can be reseted to original.
assuming lean mixture hasn't evaporated all aluminum to stratosphere.
HT
Hi John,
Really appreciate your effort in all these videos. It gives many of us "instant knowledge" to tackle our own foray into diesel heaters. I was wondering if you could expand on connections of exhaust piping. You covered connection of fuel quite well and it would be nice to see your take on the best way to connect the exhaust pipe to muffler, bend the piping, extensions etc. The pipes that come with the kit are hard to interconnect and I have seen a suppliers manual that suggest cutting a slot in pipes prior to connection to allow "pull down" by the clamp. With your experience would be good to see what you think is best for sealing and longevity. Great videos, thank you again.
Hi There, You can cut slots in the exhaust pipe end to allow joining. Use exhaust sealer or high temperature silicone to make the join gas proof. You can also use a short length (50 mm) of the right size copper, aluminium or stainless steel pipe to make a joiner, using high temp silicone to seal. JMcK
Thanks.. Great explanation.
work lab/ hands on instructions A+
Thank you. JMcK
Great videos i really enjoy them you do a good job of intelligently testing things many of us would like to know. I will be purchacing one of thease heaters for my 4x4 camping vehicle. Question the espar heaters have an option for high altitude kit is there any such thing or adjustment for thease units to run well at high altitude?
Also what parts would you reccamend carrying as spares for thease units atomizer screne, glow plug, gaskets of any kind for dissassembly and reassembly?
I saw in one of your other videos an intake air screne you were showing does that come with the units or do i buy that seporate? Curious if installed and used properly how often do they get carboned or need repair? Thanks for the great vids and info mike
Hi Michael,
Sorry I missed this post.
I know of no Chinese heater with a high altitude kit accessory. However if you run a high Kerro: Diesel mix, say 80:20, it greatly reduces the carbon buildup from a poor O2 mix from high altitude use.
Spare parts depend on the remoteness of your travels. On the boat I carry a spare glow plug, spare filter, spare gasket, and spare glow plug screen.
If set up correctly they need very little maintenance. The unit we have in the boat has not needed a service or carbon clean out in over 10 years of part time use. (See video)
JMcK
I would, provided I had the time and resources, repeat these tests with noise meter situated at a set distance (perhaps 1 metre) exactly in front of muffler exhaust. Of course noise meter would have to be repositioned as required to ensure it is exactly a metre from exhaust outlet.
Great video! Now, just to try to find if Chinese have type details of their mufflers. Mine heater came without a any muffler.
Hi Fibra, here is a start for your muffler search.
www.ebay.com.au/itm/Air-Filter-Exhaust-Silencer-Muffler-Bracket-Kit-For-Ebespacher-Diesel-Heater/183705927920?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
It is because of the back flow in the chamber is what you hear. Think of the air flow as being water flowing through it. Now if the muffler had good packing it would slow the air or water flow down, which would make the exhaust a little bit quieter exhaust. But it would have to be made bigger around, not longer to make it just a little less noise. Yes adding 2 does work together but there is a lot more going on with the air flow meaning (exhaust gases) than I would like to post.
If it was a gas combustion engine I would not be here. Diesel heaters I have no experience on, but I did check the temp on the exhaust was a little high (In my thinking anyway). I thought I could use that heat somewhere else. Like a food warmer or maybe a 5 gal hot water tank heater, I just don't know the exhaust back pressure that make these work.
Thanks for your time tho.
Chilly
Thanks for the feedback William. JMcK
Hi Michael, the Chinese have cloned the diesel water heaters as well, but they are still around the $1,000 mark for a 5 kw unit. I think perhaps in a year or so the price will come down to air heater level. That is what happened with the air heaters, they started at about half the genuine price, and then fell to a level the masses could afford one. J
Did this come to fruition? I know there's a fellow making a heat exchanger and shroud for these as of a couple months ago for about $150. No idea if it's any good.
Bobil vans in the UK doing heat exchangers for these to heat water, good prices too
Hi John, Do you have any recommended sources to buy the straight through mufflers ? Its difficult to find them; also the mufflers should come welded on the ingress/egress pipes as I have noticed that some exhaust comes from the water drain hole and between the pipe and exhaust casing on the muffler that I received with the unit
Hi, I've heard that if you use a muffler on the intake as well as the exhaust it's even more quiet!
Hi Paul, yes, provided it is not a baffled muffler like supplied in the kits. My tests showed the supplied intake muffler actually increased the noise. See video. JMcK
Is it fine to have the muffler at the end of the exhuast? Thanks for the videos, very helpful!
Sorry, I missed this Daniel. Yes, it is ok to have a muffler at the end of the exhaust. JMcK
Hey John thanks for the great video series on the CDH. I have a question regarding the exhaust outlet and the fuel inlet close proximity. When I tested out my CDH the other weekend I found that the Hard vinyl fuel line had melted closed near the fuel inlet nipple. Does the exhaust wrap work well enough to stop this from happening or should I go for a better heatshield idea like a separation plate between the exhaust and the fuel line inlet?
John - thanks for these terrific videos - they are really most helpful. A really dumb question but if the exhaust temperature is something like 400 to 650 deg F and the condensation (my exhaust run is much shorter than yours) amounts to less than a teaspoon, would not the fluid boil off within min. of firing the heater up? Thanks. John Coppedge
Hi John,
Yes that is correct in many cases.
But even with a short exhaust just a tablespoon of condensation water trapped in the exhaust can cause back pressure in the heater, preventing combustion air to enter the burner causing a hard start. The little fan in these heaters is not very powerful and you restrict the exhaust you restrict the inlet combustion air.
Also sometimes traces of unburnt diesel can leak into the exhaust. If that pools in the bottom of an exhaust loop it can be interesting when the exhaust is hot enough to ignite it. JMcK
Hello John, thank you very much for these videos, going to install one and I owe you! One question: what about 3 or 4 straight mufflers to even more reduce the noise? Would you recommend that? Thank you!
Hi Petr,
One straight through muffler is generally fine, use two or more if noise is an issue, but they must be the straight through type, not the baffled type.
Generally the annoying noise comes from the fan running at high speed and the "ticking" of the dosing pump.
Cheers, JMcK
Do you recommend using a turret mount when installing these into a caravan?, I thought as long as I cut the hole out around the intake/exhaust I should probably be okay
Hi Shane,
It is preferable to use a turret mount or similar when mounting through a plywood or composite floor.
If you can't get a turret floor plate you can use a metal 100 mm gutter down pipe adaptor to give you a metal guard around the cut out hole.
If you are unable to use a turret mount or metal line the combustion intake and exhaust hole, the cutout in the wood floor must be a minimum of 100 mm dia, and the plywood end grain well sealed against moisture.
Cheers, JMcK
On the subject of exhausts, what are your thoughts on an upright exhaust stack if the heater is sideways mounted? Considering this option to pipe the exhaust out of the roof (with the exhaust in an enclosed box like a house flue) so fumes are airborne.
Hi Mr C,
If the heater is sideways mounted you must make sure the the glow plug is on the top.
You would need a 90° bend in the exhaust to make it go upwards.
An upwards exhaust is very good and draws well but you need another bend at the top or some other form of rain deflector at the top.
You will also need a small drain hole at the bottom of exhaust to drain away condensation.
If the bottom of exhaust is in accommodation space you need a water trap condensate drain like in my boat video.
Cheers. JMcK
Very very helpful John. Thanks heaps for a great set of clips. Quick question. Can I join 3 straight through mufflers as I have them and would it be of any benefit? Thanks heaps regards Peter.
Dave McLuckie did , tho he didn't specifically address excessive restriction issues. i don't recall if he used a db meter , but a 2nd , then 3rd muffler were Very audibly noticable on the mic. As i recall tho , he was using the REALLY cheap Chi. mufflers that were EMPTY inside. Yup , that's right - EMPTY : No perf tube , NO matting , just an expansion space ! ( that's what i got with mine ) The 3rd muffler made it whisper quiet. i was quite surprised.
Thanks for the videos - very informant. Question, I am replacing a Propex propane forced air heater with one of these on our boat and am trying to use the same inlet and combustion hoses. Both hoses are slightly larger OD than the diesel (I can use a section of the supplied hoses as a shim) but the through hull is wildly different. Do you have any idea what the exhaust temperature is? Depending on the temp, I may need to add some insulation between the exhaust/inlet fitting and the hull.
Hi John,
The exhaust can reach some 100's of deg C and must be isolated from the hull.
You must also use a suitable isolation through hull. You can buy a polished ss exhaust through hull on line. Search " Eberspacher diesel heater marine exhaust through hull"
If you are a handy welder you can make your own or get one made, but probably cheaper to buy one. Have you seen my boat install video showing the through hull?. JMcK
@@johnmck1147 From a search of more videos, I am guessing 600 deg F at high output. The Propex fitting is different (you can look it up on line if you are interested) - it takes care of the input and exhaust. The air intake is just below the exhaust which may serve to keep the temp of the fitting in the reasonable range (or it did with the propane heater). It has a plate offset from the port which may also be problematic but I thought it was a really good idea since it would dissipate the inertial forces of a wave slap. Propex heaters, from LONG conversations with the factory and "local" (only 2,500 miles away) dealer trying to get the thing repaired and working (I think it is the board - I am afraid this unit is headed for the dump), is also very sensitive to combustion hose lengths, so I am hoping the diesel requirements are not too far off. Again, thanks for your help and your videos are first rate and very helpful and informative.
May I suggest a smooth wall exhaust pipe? My experience in using corrugated hoses versus smooth wall pipe on vacuum sewer cleaning equipment shows the corrugation creates turbulence resulting in a whirring or whistling noise. What are your thoughts on this?
Hi OG. Yes I agree, smooth is better than corrugated, but the heaters come with corrugated, and the vast majority of users use corrugated. In using these heaters for over 12 years now, in real life I find corrugated is not really an issue here. JMcK
Something i noticed, my vans exhaust was quieter when it started to rot and have 3-4 holes along it's length before the muffler.
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Thanks,Great, exactly was I thought about all the extensions of the outlet pipe.
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Hi John, I am retrofitting an all-in-one Chinese diesel heater per your instructions in these videos and I am wondering what your best advice is for the placement of the exhaust and air intake? I put the heater up on wooden feet so I have space underneath, but I am wondering if the exhaust pipe should be extended from the 60 cm pipe supplied and put out the front of the heater (controller side) so as not to get exhaust fumes mixed in with the fan at the back of the unit? The heater will sit next to my SUV with the heat pumped in through a long tube through my window (I am sleeping inside the car). I would then put the air intake pipe out the back.
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The muffler supplied with my heater is a spring inside a hollow stainless steel shell
Hi Mick, sounds like a type of flow through muffler. I think you will find the muffler is also packed with noise absorbent material. To see if it works just try your heater with and without the muffler. JMcK
@@johnmck1147 I thought it might have had glass wool or something so being nosey I looked inside it with a borescope and all it had inside was a little dust and some cobwebs.
Mick Ward
Good for you Mick.
All mine have glass wool inside.
I am curious now to see if there is a noise reduction without the wool. The majority of car mufflers are empty inside.
Cheers. JMcK
@@johnmck1147 the sound with the muffler on is about 3 to 5 decibels with quieter than with it off tested with a smartphone app
Mick Ward
Thanks for the info Mick.
I will have to try that phone app. I always have my phone, but I don't carry around a dB meter in my pocket. JMcK
John, I know you did these tests some 4 years ago, but is it possible to get a test done on the new rectangular mufflers now available for the CDH? Would be interesting to see what the results are. I can supplier a muffler for you if you wish. Thanks in advance.
Hi John,
Sorry for the late reply. I have recently arrived in Greece and I am doing maintenance on my boat prior to launch. Then I will be sailing for 3 months around the Med. I should be back in Australia in August. Could please contact me then about the muffler and I will be happy to have a look at it. Not sure if I would be prepared to do a video though. What type of muffler are you talking about?. Can you please give me more details.
My email is johnmck47@outlook.com. Cheers. JMcK
.
Hi Great info! Is the "baffled" muffler directional? I can't see any indications. I sort of see arrows both sides but the point at opposite direction.
I thought noise doubled ever 3 db. So wouldn't a change of 10db actually be approx 8 times louder? Great videos by the way. Very informative.
Hi 22 savage,
You are partly correct. In scientific terms 3db increase is actually twice the energy or power.
However peoples hearing is very subjective, and dependent on ones ears. In human terms a 10 db change is generally considered the level that the average person perceives as a doubling of the noise level.
Cheers. JMcK
Hi, great videos, I see the link to the pass through exhaust that you posted is no longer available, any idea what I should look for on EBAY for a pass through ?
Hi Chris, search for diesel air heater or parking heater muffler.
Here is a link to get you started in your search.
www.ebay.com.au/itm/24mm-Diesel-Heater-Exhaust-Muffler-Pipe-Silencer-Clamps-Bracket-For-Ebespacher/362935883396?epid=19023397193&hash=item5480aa1684:g:xqAAAOSwJ2pb1ryb
Regards. JMcK
Hi John your videos have been very helpful to me and others. I am installing a 2kw heater in a small boat. My exhaust will be 1.5mts long and I am considering not fitting a muffler. Reason being that the exhaust will exit the boat via a stern locker and I don't want moisture/unburnt diesel dripping into the locker from the muffler. My question' s are is it OK not to have a muffler and is it OK not to have a drain hole (No muffler)?
Hi Eric, it is not essential to have a muffler, the heater will just be a little noisier.
If the exhaust travels upwards you will need a water trap, see video on boat install. Without a water trap condensate will pool in your combustion chamber. JMcK
Thx John, very clear video. Can you say something about the heat ? How warm do the exhaustpipes become ?
Hi DM, the answer here is very variable and depends on outside temperature, exhaust restrictions, temperature setting of heater etc. But as a rule of thumb,.......300 deg C to 350 deg C, but it can go higher. JMcK
Hi John. Great set of videos.
I'm in th process of installing a 5kw heater in my boat. My heater came with 2 straight through type mufflers and from your video it looks a good idea to use both. My question is what have you found to be the best way to join thm together? Is it done by using a small length of exhaust hose, or can you buy a special bit of kit to effect the join?
Hi Graham, unless the mufflers are fully welded and gas tight they are not suitable for marine install. Mufflers that come with these heaters are just spot welded and are not a gas tight seal. You could have them fully tig welded or purchase a proper marine muffler.
For joins use some ss tube of the right size. Sometimes hard to get the right size. You can sometimes get this from a genuine Eberspacher supplier or make your own. I bought half a metre of the closest ss tube put one slit in lengthwise adjusted to right size and tig welded the slit. JMcK
@@johnmck1147 couldnt you just seal around the edges of the muffler with high temp silicone
?
Atkins Paints The World!
Yes you could, and don't forget the drain hole. But in a boat I would want my muffler fully TIG welded to eliminate any chance of CO getting into the accommodation area. The surface area of the muffler edge is very small, and lessens the chance of a good or permanent gas seal from a silicone bead. If you don't have a TIG welder (I do), a shop could probably weld the edge far cheaper than buying a dedicated marine muffler. JMcK
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Hi John sorry to ask so many questions but the more I look into fitting a unit the more queries it raises before I begin. I want to get the exhaust right as this is the most important bit. In my boat the exhaust will be about 1.5 mts slightly uphill so must I have a drain hole? The distance from water line to thru hull outlet is 52cm so no need for a loop? I guess the Eberspacer sealed muffler does not have a drain hole hence the water trap? Where to obtain a drain unit like you have on your boat and assume this just mates with the outlet on the heater unit, does this type not leak gas too? By the way your series of videos are superb-you have a wealth of knowledge. With thanks again.
Hi Eric, you should have an exhaust loop on a boat to keep out rain, sea spray, and wave slap from running back down the exhaust and into the heater.
Hot exhaust gas, as it cools, sucks into the exhaust large amounts of external cool moist air, and lots of water condenses out of this air. You need a condensate trap at the lowest point. This is usually at the heater.
The condensate trap has water in it and stops gas escaping into the boat, It works like a water trap in a toilet or a sink. You can get one made or buy on line.
Search something like " Eberspacher diesel heater condensate or marine water trap" .
A marine muffler is gas tight. Also search under Eberspacher air heater marine muffler.
Cheers, JMcK
Hi John thanks 4 all the info. now i know way my heater was smoking . Question is thare a maximum lenkt of the outgoing (warm) air ? i whant to bild a ring in mij camper. Gretings
Hi Mr Zx, the longer the length the greater the restriction and the lesser the volume. However I have seen outlet tube lengths of 10 m (30 ft) in boats that work ok.
Appreciate all your work on reviewing these heaters.
I was looking at 5kw heaters on aliexpress.com and they vary in price. My question, Are they all
made by one factory and basically the same and just marketed by different retailers or there are truly different manufactures ?
I don’t mind paying more for better quality, but I can't discern the better quality units.
Hi Ji Martin, sorry I missed this and just saw it today.
To the best of my knowledge there are a number of manufactures as the castings and cases vary slightly. Also there are a number of different manufactures making the electronics. Mostly they are excellent for the price, but you do get the odd dud, so I try and select a seller with a local country warehouse and one who advertises free returns. JMcK
How hot does the Exhaust exaust pipe get while running at maximum (boost) mode, can't recall if you used a lazer temp meter in the video or not?.
Great lesson, thanks for sharing this information with us.🇺🇸✌️
@Do One Great, I kinda figured but wasn't sure, thanks for your reply.🇺🇸✌️
Hi I've seen a comment that useing spiral pipe rather than the ribed type pipe supplied would be quieter with no silencer, than a riibed pipe with a silencer, I've ordered some but not here yet. I could not make out if you joined the two silencers with tin can rapped round and clamped, am i wrong?
Great info John.
Would you consider testing the little rectangular mufflers available on eBay?
Excellent video! I truly appreciate the time and money you have put into helping us do-it-yourselfers. Is it possible to turn the heater 90° so that the exhaust is on the side?
Yes, but the correct side must be up (glow plug up).
Dell is correct. These heaters can be side mounted but only the side with the glow plug on the top. They can run (for a while) with glow plug down, but the glow plug and screen gets flooded with left over diesel and then the heater won't start. JMcK