Autoterm 4kw heater was blowing smoke out into the cabins

[UK-WOOZY]

I have been running the heater without issues the past 2 and a bit years. i last ran it without issues about 3 months ago. boats on the hard now and i went down to it last night. thought i'd give the heater a run again as it was chilly and couldnt be bothered to plug the electric in. i was outside chatting to some club friends next thing i noted the cabin was filling up with smoke and a friend on the ground said the exhaust was glowing inside. i immediately turn off the power to the heater and checked inside the cockpit locker where it is to make sure nothing looked wrong. all looked fine. the exhaust didnt feel particularly hot though but the heater was extremely hot. so i turned it on again and ran the air cooling mode to cool it down. could the exhaust be blocked causing the fumes to back flow into the duct and cabins?
thank you

 

[Rappey]

Could the exhaust be corroded and have a hole allowing exhaust fumes to be sucked into the heater and blown out as warm air ?

 

[PaulRainbow]

I have been running the heater without issues the past 2 and a bit years. i last ran it without issues about 3 months ago. boats on the hard now and i went down to it last night. thought i'd give the heater a run again as it was chilly and couldnt be bothered to plug the electric in. i was outside chatting to some club friends next thing i noted the cabin was filling up with smoke and a friend on the ground said the exhaust was glowing inside. i immediately turn off the power to the heater and checked inside the cockpit locker where it is to make sure nothing looked wrong. all looked fine. the exhaust didnt feel particularly hot though but the heater was extremely hot. so i turned it on again and ran the air cooling mode to cool it down. could the exhaust be blocked causing the fumes to back flow into the duct and cabins?
thank you

Don't think so. Check the exhaust isn't leaking and the blown air intake isn't sucking in the exhaust fumes.

 

[UK-WOOZY]

thank you for the replies. i will check that with a shop vac. but when i opened the cockpit locker no smoke was inside or came out. was a lot of smoke in the boat. the exhaust is the exhaust with silencer from autoterm. i thought i have the standard vehicle exhaust and and silencer that came with it, i could connect that to see if it is the marine exhaust at fault or not? Could the burn chamber be coked up its blocking the exhaust? also if the exhaust is blocked too could the fumes go out the duct side of the heater?

Anyone know of a diesel heater mechanic around the medway area?

 

[owen-cox]

It sounds like the heater is badly sooted and the soot in the exhaust is catching fire. After running fine for 2 years i would suspect fuel quality as shelf life is so short now and causes sooting very often. It will need a strip and clean to resolve it. Uoi can send it to us at autoterm if you want and we can do it.

 

[UK-WOOZY]

yes please owen. it will be a pain in the behind to disconnect everything as i used exhaust compound on the connections but that sounds the best solution to me if there is no one based in kent to look. are you able to check the exhaust too?

 

[PaulRainbow]

It sounds like the heater is badly sooted and the soot in the exhaust is catching fire. After running fine for 2 years i would suspect fuel quality as shelf life is so short now and causes sooting very often. It will need a strip and clean to resolve it. Uoi can send it to us at autoterm if you want and we can do it.

Curious, how does soot in the exhaust get into the boat ?

 

[fredrussell]

Pro-Chinaspacher movement rubs it’s hands and, as a whole, retains this bit of intel for later debates…
…Those of them that haven’t been asphyxiated by their heaters, that is.

 

[owen-cox]

Curious, how does soot in the exhaust get into the boat ?

The issue is that the back pressure on the exhaust eventually pushes fumes out pas the rubber seal around the fuel pipe to the burner. Its the same in all diesel heaters as they all have a rubber seal in there. Usually they wont actually run when they are that bad but its one reason we recommend a CO alarm. As i say poor fuel quality is the usual root cause. The lighter elements of the fuel evaporate off and leave heavier oils that don't burn easily. Engines as they run much hotter and at very high pressures are not so susceptible to this issue but it kills any type of diesel heater.

 

[owen-cox]

Pro-Chinaspacher movement rubs it’s hands and, as a whole, retains this bit of intel for later debates…
…Those of them that haven’t been asphyxiated by their heaters, that is.

Its exactly the same on chinaspacher heaters. They have seals that in my experience are not so well designed or made and so are actually more likely to leak.

 

[UK-WOOZY]

it didnt set my x2 c02 alarms off (one in stern cabin where the first vent is and the other in the galley the second vent)

 

[owen-cox]

it didnt set my x2 c02 alarms off (one in stern cabin where the first vent is and the other in the galley the second vent)

Thats good news then because although there was smoke there it was not enough to be dangerous. Anyway. If you send it to our workshop(address on website) we can service it and check it and return it. Make sure you put in a description of the fault and contact details in the package. Once its working again the exhaust will smoke badly as that will still have soot/ unburnt fuel in it. So keep an eye on it and it should clean up by running the heater at full power for an hour.

 

[PaulRainbow]

The issue is that the back pressure on the exhaust eventually pushes fumes out pas the rubber seal around the fuel pipe to the burner. Its the same in all diesel heaters as they all have a rubber seal in there. Usually they wont actually run when they are that bad but its one reason we recommend a CO alarm. As i say poor fuel quality is the usual root cause. The lighter elements of the fuel evaporate off and leave heavier oils that don't burn easily. Engines as they run much hotter and at very high pressures are not so susceptible to this issue but it kills any type of diesel heater.

Thanks for clarifying Owen. My diesel gets turned over quicker than the typical yacht, we refill every 6 months or so. The 4Kw Autoterm that i fitted about 3 years ago never misses a boat, it's currently keeping a 45ft boat warm enough, when it gets really cold we turn the second heater on.

 

[UK-WOOZY]

ok, thank you Owen. Ill remove it next weekend. I do also run this fuel filter, i also use the separate fuel tank it came with. I topped up with new fuel onto existing around 2 months ago.

 

[UK-WOOZY]

on another note. is there better ducting available without the need to insulate it as the aluminium duct gets bent and torn very easily in the locker. i have only ever been able to heat the stern cabin and galley never had enough heat to heat the forward cabin on my small 30ft boat which i suspect is due to heat loss in the ducts

 

[wonkywinch]

... i immediately turn off the power to the heater ...

I appreciate this was an emergency situation but in normal use, never switch off the power to a diesel heater to stop it. They have a built in shut down cycle controlled by the panel "on/off" switch but need to be powered up to allow the fan to run on.

You'll trash the heat exchanger and void any warranty by pulling the plug to shut it down.

 

[UK-WOOZY]

I appreciate this was an emergency situation but in normal use, never switch off the power to a diesel heater to stop it. They have a built in shut down cycle controlled by the panel "on/off" switch but need to be powered up to allow the fan to run on.

You'll trash the heat exchanger and void any warranty by pulling the plug to shut it down.

i was worried something was on fire inside the unit that shouldnt have been on fire. but all other times in use i used the shut down on the comfort control or via the app on my phone

 

[owen-cox]

Thanks for clarifying Owen. My diesel gets turned over quicker than the typical yacht, we refill every 6 months or so. The 4Kw Autoterm that i fitted about 3 years ago never misses a boat, it's currently keeping a 45ft boat warm enough, when it gets really cold we turn the second heater on.

We can Check the diagnostic data and see if there are any other obvious issues. The data can tell us a lot about how the heater runs. Ducting restrictions and exhaust flow restrictions can all cause sooting as well as cab running at a constant low power without giving it a long blast at full power every now and again. But usually it’s fuel.

 

[oldgit]

Irrespective of the make, aways tried to run all my warm air heaters, from my first ancient Ardic, the ancient ex post office weedy D1, an Autoterm, Chinaspacher to my current D5, as hot and as hard and as long as possible.
Always a few mid summer start ups, all ran on whatever was in the the main fuel tank.
Have yet to need a de coke on any.
If anything ever died it was the cost of something electrical or mechanical from Eber which led to it being replaced.
If/when the D5 dies, doubt much prevarication about what will replace it.

 

[UK-WOOZY]

Owen. Sorry to badger you, i pm'd you