FBH possible oddity

Raistlin · 9th December 2008, 18:51

I've searched but can't find quite what I need to know

My FBH detects low ambient temp and fires up when I start the car. Unfortunately, it still seems to be running after a 10 mile drive when the engine has been up to normal running temperature for some time.

I can't remember my old car's FBH doing the same.

Any ideas please?

FROGGY · 9th December 2008, 18:54

Off the top of my head, but if your 'stat is stuck open, perhaps the water temp isn't getting high enough to turn thr FBH off?

Mick

Raistlin · 9th December 2008, 18:58

Heater output is very good Mick so I'd guess water temperature was OK.

Water temperature gauge in its usual mid way position.

Thanks for the idea though

CDTi · 9th December 2008, 19:15

Quote:

Originally Posted by Raistlin

I've searched but can't find quite what I need to know

My FBH detects low ambient temp and fires up when I start the car. Unfortunately, it still seems to be running after a 10 mile drive when the engine has been up to normal running temperature for some time.

I can't remember my old car's FBH doing the same.

Any ideas please?

Actually I have just discovered the exact same thing, Paul.

As you know I only fitted my FBH earlier this year so its only been in use a few times so far. However I noticed today that the FBH continued to run even after a 10/12 mile drive. I don't know if this happens every trip.

I have the older PCB if that makes a difference and the stat is OK.

madone · 9th December 2008, 19:52

Quote:

Originally Posted by Raistlin

I've searched but can't find quite what I need to know

My FBH detects low ambient temp and fires up when I start the car. Unfortunately, it still seems to be running after a 10 mile drive when the engine has been up to normal running temperature for some time.

I can't remember my old car's FBH doing the same.

Any ideas please?

Have you done the diagnostics check to see what the actual temp is?

FROGGY · 9th December 2008, 20:26

Paul

When you say it is still running, do you mean at "full blast", or is it running in its "idle" or "part load" state.

IIRC from my reading up, it goes through a heating stage, switches to a part load stage, then a controlled idle stage. These are all water temperature governed. If the water temperature falls below a certain level, then the full load operation starts again.

( I can't remember the temp figures, but can find them if needed).

Mick

apywell · 9th December 2008, 20:32

I've noticed mine still running after I get to work and it had been on running temp for a good 10 mins. Lates replaced my thermo about 7 months ago so shouldn't be a thermo issue.

Raistlin · 9th December 2008, 21:28

It's not on full blast Mick. Stops a few minutes after the engine is switched off.

I'm concerned about it running all through the journey though.

CDTi · 9th December 2008, 22:38

Quote:

Originally Posted by apywell

I've noticed mine still running after I get to work and it had been on running temp for a good 10 mins. Lates replaced my thermo about 7 months ago so shouldn't be a thermo issue.

Quote:

Originally Posted by Raistlin

It's not on full blast Mick. Stops a few minutes after the engine is switched off.

I'm concerned about it running all through the journey though.

Yep, thats exactly like mine.

Jules · 9th December 2008, 23:24

Our last 3 FBH cars have all run in part load state, after a run .....if the outside temp was below 5 deg!
That's not to say this is normal though.

Maybe Keith (FBH Maestro) could shed some light on this:xmas-smiley-022:

9th December 2008, 18:51	#1
Raistlin Banned 75 CDT Connoisseur SE Auto Join Date: Nov 2006 Location: Wolverhampton Posts: 8,450 Thanks: 0 Thanked 3 Times in 3 Posts	FBH possible oddity I've searched but can't find quite what I need to know My FBH detects low ambient temp and fires up when I start the car. Unfortunately, it still seems to be running after a 10 mile drive when the engine has been up to normal running temperature for some time. I can't remember my old car's FBH doing the same. Any ideas please?

9th December 2008, 18:54	#2
FROGGY I really should get out more....... MG ZT CDTI Join Date: Sep 2007 Location: 17500 REAUX, CHARENTE-MARITIME Posts: 2,749 Thanks: 2 Thanked 133 Times in 90 Posts	Off the top of my head, but if your 'stat is stuck open, perhaps the water temp isn't getting high enough to turn thr FBH off? Mick __________________ http://i200.photobucket.com/albums/a...ps628d4119.jpg IN THE BLACK NOW

9th December 2008, 18:58	#3
Raistlin Banned 75 CDT Connoisseur SE Auto Join Date: Nov 2006 Location: Wolverhampton Posts: 8,450 Thanks: 0 Thanked 3 Times in 3 Posts	Heater output is very good Mick so I'd guess water temperature was OK. Water temperature gauge in its usual mid way position. Thanks for the idea though Last edited by Raistlin; 9th December 2008 at 19:00..

9th December 2008, 20:26	#6
FROGGY I really should get out more....... MG ZT CDTI Join Date: Sep 2007 Location: 17500 REAUX, CHARENTE-MARITIME Posts: 2,749 Thanks: 2 Thanked 133 Times in 90 Posts	Paul When you say it is still running, do you mean at "full blast", or is it running in its "idle" or "part load" state. IIRC from my reading up, it goes through a heating stage, switches to a part load stage, then a controlled idle stage. These are all water temperature governed. If the water temperature falls below a certain level, then the full load operation starts again. ( I can't remember the temp figures, but can find them if needed). Mick __________________ http://i200.photobucket.com/albums/a...ps628d4119.jpg IN THE BLACK NOW

9th December 2008, 20:32	#7
apywell Gets stuck in Rover 75 Saloon. 2.0 Diesel Auto. Connoisseur SE. Join Date: Nov 2006 Location: Derby Posts: 723 Thanks: 0 Thanked 0 Times in 0 Posts	I've noticed mine still running after I get to work and it had been on running temp for a good 10 mins. Lates replaced my thermo about 7 months ago so shouldn't be a thermo issue. __________________ If there's one thing I've learned, it's that life is one crushing defeat after another until you just wish Flanders was dead. Now has an S-Type 2.7 diesel V6 twin turbo with Jag voice, bluetooth, sat nav, front and rear park assist, electric fold mirrors etc, etc, etc.....

9th December 2008, 21:28	#8
Raistlin Banned 75 CDT Connoisseur SE Auto Join Date: Nov 2006 Location: Wolverhampton Posts: 8,450 Thanks: 0 Thanked 3 Times in 3 Posts	It's not on full blast Mick. Stops a few minutes after the engine is switched off. I'm concerned about it running all through the journey though.

9th December 2008, 23:24	#10
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Our last 3 FBH cars have all run in part load state, after a run .....if the outside temp was below 5 deg! That's not to say this is normal though. Maybe Keith (FBH Maestro) could shed some light on this:xmas-smiley-022: __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block