Why does my FBH not turn the blowers on??

[Pete_901]

It seems to be cutting out when the coolant gets to 66 degrees and it also doesn’t turn the ATC on. Any ideas?

[Avulon]

I'm guessing - but probably going to need a bit more info in this question for anyone to be able to answer. By default (without timer/remote) the oem fbh starts only when the engine is running and the temp below 5C and will turn off before it reaches 70c coolant temp. If you're starting it with a remote without the engine running then provide the details - oem or retrofit? what parts are fitted etc...

[Pete_901]

It’s a genuwine heater fitted with a timer in the cubby hole. Press the flame button and you can hear it start up and the pump ticking away, after about 5mins it just shuts down. No blowers or anything! I sent it to French mike and he said there was a glowpug fault (heater wasn’t working at all) stripped the heater and cleaned it out when I got the pcb back and it fired for the first time, but just cuts out after around 4-5mins. Am I right to thinking the glowplug is at fault?

[Arctic]

Hi Peter.
You could do worse than drop Devlish a PM he maybe able to help you

[Avulon]

From you description it would appear that it's either not firing up or is cutting out prematurely for some reason. Have you checked the dosing pump for correct function?

[Pete_901]

Originally Posted by Avulon

From you description it would appear that it's either not firing up or is cutting out prematurely for some reason. Have you checked the dosing pump for correct function?

its firing up correctly and making the coolant warm. dosing pump is working as it should and gets quicker etc. for some reason the pump stops after about 5mins and shuts everything down. doesn't turn the blowers on or anything and stops at about 45-50 degrees.

mike had the PCB and its ok, it was showing a glow pin fault and it wasn't firing at all but it works now ive stripped and cleaned everything, except for obviously now its just cutting out after 5-6mins

[HarryM1BYT]

Originally Posted by Pete_901

its firing up correctly and making the coolant warm. dosing pump is working as it should and gets quicker etc. for some reason the pump stops after about 5mins and shuts everything down. doesn't turn the blowers on or anything and stops at about 45-50 degrees.

mike had the PCB and its ok, it was showing a glow pin fault and it wasn't firing at all but it works now ive stripped and cleaned everything, except for obviously now its just cutting out after 5-6mins

It was only designed as a system to pre-heat the coolant and the engine. The heater blower is not supposed to run at all, although there is a modification which someone designed, which allows the blower to run, once the coolant is hot, to warm the cabin up. Be aware that running the FBH and the blower for an extended time, will knock lumps out of the batteries charge.



So, if the FBH is burning and heating the coolant and the engine up, it is doing all that it is designed to do. It should heat the coolant to 77C, as measured at the FBH output - how are you determining that it shuts down at 45to 50C ?

[Pete_901]

Originally Posted by HarryM1BYT

It was only designed as a system to pre-heat the coolant and the engine. The heater blower is not supposed to run at all, although there is a modification which someone designed, which allows the blower to run, once the coolant is hot, to warm the cabin up. Be aware that running the FBH and the blower for an extended time, will knock lumps out of the batteries charge.



So, if the FBH is burning and heating the coolant and the engine up, it is doing all that it is designed to do. It should heat the coolant to 77C, as measured at the FBH output - how are you determining that it shuts down at 45to 50C ?

I thought that because it has the timer in the center consol cubby hole that it turns the blowers on once the coolant is warm then all shuts off when the coolant reachs 77c? so it defrosts your car in the winter. is this not correct? I used to diag in the instrument cluster to check on what temp the coolant is when the FBH is operating

[HarryM1BYT]

Originally Posted by Pete_901

I thought that because it has the timer in the center consol cubby hole that it turns the blowers on once the coolant is warm then all shuts off when the coolant reachs 77c? so it defrosts your car in the winter. is this not correct? I used to diag in the instrument cluster to check on what temp the coolant is when the FBH is operating

No, it is not correct. It is no good looking at the instrument diagnostics, because that will show a much lower temperature than that at the FBH itself. The FBH measures its temperature at its output, which it then uses to modulate its heat output. The FBH's electric water circulation pump, is tiny by comparison to the engines circulation pump, so there will not be anything like the same level of coolant flow through the system.



Really, the FBH was fitted, just to improve the very slow warmup of the diesel engine in cold weather and it does that quite effectively. It was never a factory option to have the FBH pre-warm the cabin.

[first-things-first]

I think you are wrong Harry. Probably depends on if you have the timer and remote switch on fitted as well?

My car (with factory FBH and timer) starts the blower with the FBH with no intervention from me. I just switch it on with the remote.

I think you may have to have left the climate on auto (before switching off engine) for it do this, IIRC ...