Urgent service Chinese diesel heater

[Dapph2]

Being serious now, it's more likely a tuning issue, rather than the length of exhaust.

When my first one died because the motor gave up, the burn chamber was pretty much spotless.
The second one that I fitted, lasted a few weeks before it faulted due to carbon build up.

I didn't bother checking it with a meter when I reinstalled it, but I leaned the mix off a bit and it's been fine since.

Interesting .

Unburn fuel caused the sooting up either because of not enough air or too much fuel delivery my engineering days tell me , Whilst I was cleaning the combustion chamber for Fizzy I was trying to envisage circumstances in which it happened . Fizzy's vertical pipe is 10 foot long and he has two 90 % angles in the flexi pipe close to the burner .

My mancupboard burner has one 90 degree turn a few inches below my unit and once through the insulated tube in the wall another 90 angle then into a 4m aluminium pipe slightly angled downward to run out any condensate that might accrue on a very cold night /day .

I've watched the exhaust discharge come out several times and it was very clean and visible six or more feet up from the top i=of the end of the pipe . The exhaust pipe itself is not clogged , stuck my finger in the pipe and it came out fairly clean as the soot was hard and not jet black
I'm thinking if the controller is the cause of the problem ... we shall see ......when the spare heater is built up and commissioned.

Thinking over what you've said about the motor M_C that would fit in for not enough air for full combustion for the fuel , then slow soot ignition to glow and burn the element till after several such session it ends up like it did ..

Happen Fizzy will conduct a motor speed test on the old unit with the original controller unit .. Though I'd just bin it all as it's not reliably repairable and save myself a lot of wasted time when I've got better more pressing things to do .

 

[m_c]

Interesting .

Unburn fuel caused the sooting up either because of not enough air or too much fuel delivery my engineering days tell me , Whilst I was cleaning the combustion chamber for Fizzy I was trying to envisage circumstances in which it happened . Fizzy's vertical pipe is 10 foot long and he has two 90 % angles in the flexi pipe close to the burner .

My mancupboard burner has one 90 degree turn a few inches below my unit and once through the insulated tube in the wall another 90 angle then into a 4m aluminium pipe slightly angled downward to run out any condensate that might accrue on a very cold night /day .

I've watched the exhaust discharge come out several times and it was very clean and visible six or more feet up from the top i=of the end of the pipe . The exhaust pipe itself is not clogged , stuck my finger in the pipe and it came out fairly clean as the soot was hard and not jet black
I'm thinking if the controller is the cause of the problem ... we shall see ......when the spare heater is built up and commissioned.

Thinking over what you've said about the motor M_C that would fit in for not enough air for full combustion for the fuel , then slow soot ignition to glow and burn the element till after several such session it ends up like it did ..

Happen Fizzy will conduct a motor speed test on the old unit with the original controller unit .. Though I'd just bin it all as it's not reliably repairable and save myself a lot of wasted time when I've got better more pressing things to do .

Officially, the heaters should be tuned using a CO meter once installed.

There's no need to test the motor speed, as the controller monitors it (there's a little magnet on the impellor that triggers a hall sensor on the controller) so if the motor isn't running at the speed the controller thinks that it should be running at, then a fault is triggered.
Tuning simply alters the ratio between the fuel pump and motor speed, but there does appear to be limitations with some of the controllers as to how effective tuning them actually is.