Measuring some temperatures on a 2KW Chinese diesel heater with wrapped exhaust. This is just for reference and it is nowhere near professional measurements.
Exhaust heat recovery is not an aim in this video, but for other applications, it does serve to remind us just how much heat we are wasting through the exhaust.
Thanks a ton. I've been looking all over for some temp readings on the exhaust on these. Trying to figure out what material would work to wrap it in. Looks like it stays under 600F for the most part which means a high temp fiberglass pipe insulation might work.
Thanks a lot for sharing your testing. I just bought silicon to seal exhaust but it can only stand 300C, did not realise the exhaust could hit 350C ! Did you 3d print the red/orange stands ?
I have a Vevor 8kW heater and I can confirm that the combustion exhaust is at least twice as hot as the clean hot air exhaust. What an appalling performance for the heat exchanger radiator. We need much bigger and much more efficient 3D-printed radiators to extract the most heat from the combustion chamber and gases, but also to ensure that both the combustion and heating circuits are completely separate (too many joints and other possible sources of combustion gas leaking in the current design), as well as ensuring that the cold clean air is pre-heated to 300°C before entering the combustion chamber. Right now, these diesel heaters are a huge waste of energy and force the user to tinker around to retrieve this wasted heat. It's good to have 2 sources of heat, clean and dirty air, but there is a serous lack of after-market products such as a mass heater which would nicely complement the heater with a solution that will continue to radiate heat for several hours after the heater is stopped. A proper power supply should also be incorporated into the case, with a switch, a battery and a trickle charger. These manufacturers probably can't do it for liability and certification reasons (it's supposed to be a 12V vehicle heater, not something you plug on an outlet), but we're lacking standard design plans and list of parts to make it easier to implement, so I'll have to figure it out for myself, based on all these CZcams videos.
A bit confused as to the effect of the wrap: Exhaust at body = 145C/293F but Exhaust air output at end is 348C/658F. Doesn't seem to make sense that with the wrap the pipe is hotter further away from the exhaust point on the heater. Does this mean the wrap actually keeps the gas hotter? If so, this confirms what a muffler guy told me: The wrap actually holds the heat in and causes more metal expansion and other issues.
This is what I was suspecting too, it stops the heat from dissipating and ejects it out the exhaust and concentrates it within the metalwork of the exhaust itself. Going to end up with stress fractures...
@@Ra-zor Interesting. I was thinking the same thing. After all, it's insulation, yes? The exhaust pipe heat dissipates when in open air, naturally making the temp of the exhaust at the end be cooler than if it was insulated. I believe insulation tape was made so a fool wouldn't burn themselves, wires or plastic crap that encompasses an exhaust pipe.
I want to make an oven for cooking pizza using the exhaust gas. The pizza is supposed to be cooked at 400F. The exhaust is hot enough, now I have to figure out how to capture it without getting smoke in the food.
Particularly important on the exhaust. The expansion of gasses due to heat increase, combined with the increase in volume from chemically turning a liquid fuel to a gas, gives more than double the volume of exhaust compared to the input air, yet it still has to discharge through the same size port and exhaust pipe. This doubles the speed of exhaust gases and since resistance to gas flow [ie backpressure] dramatically rises with increase in gas speed, the fan unit has to work hard. Any additional bends introduced will make this much worse, and will further restrict the gas flow and tend towards a fuel rich incomplete burn That little fan already has a tough job, don't make it worse with added restrictions..
Which is why and please someone correct me, these people on YT putting these heaters into an encased plastic container are saying they have a success...
Have you seen the videos of the guy using a small carburetor off a remote control airplane/car to enable drip feed and so doing away with the controller and fuel pump. He runs his on its side to enable the drip feed.
Really needed before and after comparisons to understand the drop and advantage of the insulation! What was the temperature at the exhaust output before the muffler without the heat wrap?
I got it from here: www.aliexpress.com/item/ZS-MOTOS-5M-10M-15M-Thermal-Exhaust-Header-Pipe-Tape-Heat-Insulating-Wrap-Tape-Fireproof-Cloth/32824657146.html
Exhaust heat recovery is not an aim in this video, but for other applications, it does serve to remind us just how much heat we are wasting through the exhaust.
Thanks a ton. I've been looking all over for some temp readings on the exhaust on these. Trying to figure out what material would work to wrap it in. Looks like it stays under 600F for the most part which means a high temp fiberglass pipe insulation might work.
Thanks a lot for sharing your testing. I just bought silicon to seal exhaust but it can only stand 300C, did not realise the exhaust could hit 350C ! Did you 3d print the red/orange stands ?
this is invaluable info thanks!
I have a Vevor 8kW heater and I can confirm that the combustion exhaust is at least twice as hot as the clean hot air exhaust. What an appalling performance for the heat exchanger radiator. We need much bigger and much more efficient 3D-printed radiators to extract the most heat from the combustion chamber and gases, but also to ensure that both the combustion and heating circuits are completely separate (too many joints and other possible sources of combustion gas leaking in the current design), as well as ensuring that the cold clean air is pre-heated to 300°C before entering the combustion chamber.
Right now, these diesel heaters are a huge waste of energy and force the user to tinker around to retrieve this wasted heat. It's good to have 2 sources of heat, clean and dirty air, but there is a serous lack of after-market products such as a mass heater which would nicely complement the heater with a solution that will continue to radiate heat for several hours after the heater is stopped. A proper power supply should also be incorporated into the case, with a switch, a battery and a trickle charger. These manufacturers probably can't do it for liability and certification reasons (it's supposed to be a 12V vehicle heater, not something you plug on an outlet), but we're lacking standard design plans and list of parts to make it easier to implement, so I'll have to figure it out for myself, based on all these CZcams videos.
Wonderful! Thank you
A bit confused as to the effect of the wrap:
Exhaust at body = 145C/293F but Exhaust air output at end is 348C/658F. Doesn't seem to make sense that with the wrap the pipe is hotter further away from the exhaust point on the heater. Does this mean the wrap actually keeps the gas hotter? If so, this confirms what a muffler guy told me: The wrap actually holds the heat in and causes more metal expansion and other issues.
This is what I was suspecting too, it stops the heat from dissipating and ejects it out the exhaust and concentrates it within the metalwork of the exhaust itself. Going to end up with stress fractures...
@@Ra-zor Interesting. I was thinking the same thing. After all, it's insulation, yes? The exhaust pipe heat dissipates when in open air, naturally making the temp of the exhaust at the end be cooler than if it was insulated. I believe insulation tape was made so a fool wouldn't burn themselves, wires or plastic crap that encompasses an exhaust pipe.
I want to make an oven for cooking pizza using the exhaust gas. The pizza is supposed to be cooked at 400F. The exhaust is hot enough, now I have to figure out how to capture it without getting smoke in the food.
Hey dude... you still alive?
Good video!
Did that tape smoke / stink for a while in the beginning? Mine somehow does. Of so, for how long did you have to burn it off?
No it did not, but I made it wet first and then wrap it up, there was only vapor of the water after that there was no smell.
They might be efficient but with exhaust temperatures like that they could be a whole lot better
FYI supposed to have very slight bends, if any at all. def dont want to stress out that lil fan
Particularly important on the exhaust. The expansion of gasses due to heat increase, combined with the increase in volume from chemically turning a liquid fuel to a gas, gives more than double the volume of exhaust compared to the input air, yet it still has to discharge through the same size port and exhaust pipe. This doubles the speed of exhaust gases and since resistance to gas flow [ie backpressure] dramatically rises with increase in gas speed, the fan unit has to work hard. Any additional bends introduced will make this much worse, and will further restrict the gas flow and tend towards a fuel rich incomplete burn That little fan already has a tough job, don't make it worse with added restrictions..
Thank you for that.
Great tips ~ thanks
Thank you for the great information. What can you tell me about the mounting feet under the heater?
That was a quick 3D sketch I designed, and printed on a 3D printer.
@@NoMercy1900 do you have the stl?
Which is why and please someone correct me, these people on YT putting these heaters into an encased plastic container are saying they have a success...
Hey mate, have you had any issues mounting the unit on its side? If I can mount it that way It'll make routing the exhausts much easier. Cheers
No problems at all, make sure the glow plug is on the upper side when you mount it like this.
Have you seen the videos of the guy using a small carburetor off a remote control airplane/car to enable drip feed and so doing away with the controller and fuel pump. He runs his on its side to enable the drip feed.
If you ever have a no start diesel could pool in the burning chamber. That’s not a good thing.
Really needed before and after comparisons to understand the drop and advantage of the insulation! What was the temperature at the exhaust output before the muffler without the heat wrap?
at 1:10 you can see him reading the bare pipe. which is 30 to 40 degrees hotter than the wrapped part.
@@MK3--- Ah, so you can! ooops...
why wrap it ?
To reduce the heat, this is build in the boot of a car.
À quoi sa sert ?
What is that wrap material? Where did you get it? Thanks.
I got it from here: www.aliexpress.com/item/ZS-MOTOS-5M-10M-15M-Thermal-Exhaust-Header-Pipe-Tape-Heat-Insulating-Wrap-Tape-Fireproof-Cloth/32824657146.html
You can get exhaust wrap from Ebay or Amazon or any hi performance auto shop