- Thread starter R Kraft
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Scalarocco
Smile, or I'll bite your leg...
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I would have said that exhaust was far too restrictive. I'm sure there is a limit to the number of bends you can have.
JOEPRO
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Yes a pipe bender would be better for the copper VS those small solder fittings.
But the principle is sound enough to recover as much heat as possible I will probably adopt something similar
JOEPRO
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I am not looking forward to core drilling my garage masonry cavity wall.
With some 28mm copper pipe I could clip it along the wall inside and exit the exhaust through an old door frame or through the roof eaves as it should be cool enough to do so if there is say 4 - 5metres of heat extraction pipework before the exhaust point.
With some 28mm copper pipe I could clip it along the wall inside and exit the exhaust through an old door frame or through the roof eaves as it should be cool enough to do so if there is say 4 - 5metres of heat extraction pipework before the exhaust point.
JOEPRO
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The design of these heaters is that the combustion inlet takes fresh air from outside the "vehicle" so as to avoid any combustion fumes entering the occupied space in the event of a fault or backfire. Your setup is correct as far as that goes however if you can keep the air inlet as far away from the exhaust as possible it will ensure that the fuel air mixture is correct. If the exhaust accidently fed back into the inlet due to a breeze etc. there would be less oxygen for combustion and the efficiency will go down. probably not a big issue in this setup but worth noting for other installs.
The space heating is setup incorrectly as the heat exchanger totally isolates the combustion and the space heating. The combustion takes place inside a cast aluminium heat exchanger and the room air is passed over this finned block of aluminium. The maximum temperature of this is below 200 degrees C and more likely only 150 degrees C. You are concerned that this may be a potential ignition source if the internal room air is passed over the heat exchanger which is a healthy attitude to take. However the ignition temperature of petrol, for instance is 220C and cellulose thinners is 475C so not as big a risk as you may imagine.
As you have chosen to take cold fresh air from outside to feed the space heating it will take considerably more power (fuel) to heat the room as the temperature difference will be high to start with and will increase as the room warms. In fact the heater will end up burning fuel for no purpose. In a small space this will be negligible as the thermostat in the controller will ramp down the output. There is however another aspect that you may have missed. As you are pumping air into the space from outside to feed the space heater you must have a vent out of the space to release the same amount of air. This means having a 75mm hole in the wall to allow the heated air out so as to not restrict the airflow over the heat exchanger. This vent should be as low down the wall as possible so that the coldest air in the room is vented first. For this example I have assumed that the doors and windows are well sealed but in reality there may be plenty of natural ventilation to preclude the need for a vent to outside.
I'll get of my lectern now and say its up to the installer to decide what is and isn't safe and it's up to physics to tell you what is and isn't efficient
On my install I've mounted my heater up near the ceiling with an extended vent pointed down which is possibly the worst way to install it but I had no floor space where I could fit it so it is what it is. I have also extended the exhaust along the internal wall and fitted radiator plates on it to gain as much heat output that I can. I used 22mm copper pipe which amazingly was the cheapest way to do it and was a great fit onto the existing exhaust. The radiator plates are some Alu plate attached with 22mm copper pipe clips and it's all painted VHT matt black. It is surprisingly efficient and I can see 180 C at the exhaust reducing down to 40 C where it goes through the wall. It's less than 3m and a straight pipe so does not restrict the exhaust. Because of the length I don't need the silencer (they don't do much anyway) but if I did I would put it at the far end outside the workshop which is 54 square metres BTW.
Can you share photos of your setup please and exhaust?
It sounds very good to me
500e
Always buy fire insurance a flood is a hard start
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Have posted on exhaust heat recovery before.
Would think that pipe would restrict the ex and cause carbon build up, also it has to vent outside. You could die.
Have had a hand in 5 my suggestion is at least 2mtrs of 100/150mm pipe angled down or you will have condensate problem, the thicker the pipe the better for heat retention.
Mains psu's are not good, switch off they stop mains fail they stop it will shorten the life and cause carbon build up, if you run like @fizzy flat out for extended periods OK.
Have done 2 with the big exhaust works well, one with an 8Mtr run
Would think that pipe would restrict the ex and cause carbon build up, also it has to vent outside. You could die.
Have had a hand in 5 my suggestion is at least 2mtrs of 100/150mm pipe angled down or you will have condensate problem, the thicker the pipe the better for heat retention.
Mains psu's are not good, switch off they stop mains fail they stop it will shorten the life and cause carbon build up, if you run like @fizzy flat out for extended periods OK.
Have done 2 with the big exhaust works well, one with an 8Mtr run
There really is no need to worry about the odd powercut. My heaters are often switched off without proper shut down procedures. Or were until I pointed put the error of their ways! One of my heaters ran for over 5000 hours with no problems at all. Until I was ill in hospital and a well meaning mate of mine filled the fuel tank with bleach instead of kero
I love his videos. He sounds like the chap that used to narrate "Little nose" I used to watch as a kid.
Remember and make sure the garage is as air tight as possible for maximum
jordhandson
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dont leave that exhaust inside
Scalarocco
Smile, or I'll bite your leg...
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You'll need one of these...
Brilliant installationI have mine going now, I think I'm going to leave it as is. This way I get a pleasant breeze in my face when working at vice
View attachment 388719
JOEPRO
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I think I have to realign my expectations somewhat or there is something wrong.
I have a double garage. Block cavity walls and a large non insulated roller shutter and single glazed window. Large loft hatch still to be covered over I'll do that tomorrow.
Even in "Facegriller 3000" mode I had it running for 40 mins or so and whilst the chill was out of the air near the heater it still had put no real Dent in the space heating.
I did also notice am air pocket in the green diesel tube below. Is this normal?
It was pumping out heat but maybe my garage is simply too large for it or it has to run for several hours to get up to temp.
What size of space do you heat? (large side)
Scalarocco
Smile, or I'll bite your leg...
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My workshop is 3 metres x 6 metres and it is uninsulated. When the outside temperatures are around 5°c it just takes the chill off but it isn't what you would call warm. Below zero it just can't make a dent in it but it is still nice to just stand in front of it to warm up periodically! I've no doubt if I insulate the roof and the big steel radiator door at one end would improve things. It's on my to-do list for this year.
Mine manages to raise my main workshop which is about 12x40ft single block wall, with a lightly insulated roof, a few degrees after 30 minutes of running. If it's on for a couple of hours, and it's sub zero outside, it'll make it tolerable to work.
However I did fill lots of gaps with expanding foam after I installed it, as drafts make a more noticeable difference than lack of insulation. Which reminds me I really need to find some perspex to fill the gap above the door into the other part of the shed, to cure the biggest remaining draft.
However I did fill lots of gaps with expanding foam after I installed it, as drafts make a more noticeable difference than lack of insulation. Which reminds me I really need to find some perspex to fill the gap above the door into the other part of the shed, to cure the biggest remaining draft.
JOEPRO
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