Front & Rear Heater Issues

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Gdlee1976
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Front & Rear Heater Issues

Post by Gdlee1976 » Thu Jan 14, 2016 2:19 pm

Hey everybody, I've used the search function but I have come up blank...
Here's what I've got...
P Reg ('96)
2.5L Diesel
Manual Controls on the Heater Panel & a rear control as well...

Front heater gets warm but not as hot as I assume it should. All of the cables are connected at the drivers & passengers footwell and the bonnet and all the vents switch as they should between foot, defrost and head.
Engine temp runs consistently at this temp...
Image

Rear heater blows but is only cold air, not warm at all.

Any ideas of what the problems could be with each??
Thanks for the help!!
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mikeonb4c
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 3:07 pm

Is there any sign of rust staining / scale in your header tank? If you squeeze the top hose when engine cold, does it feel rigid and/or crunchy as you squeeze it. If either of these apply, its possible the heater matrix has been affected by clogging up. Otherwise, do you have any reason to believe the coolant system might not have been bled properly following coolant refill/replacement? How long has it been like that - did it come on gradually or did it happen suddenly.
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cmm303
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Re: Front & Rear Heater Issues

Post by cmm303 » Thu Jan 14, 2016 3:23 pm

Is the heater matrix getting hot? For the back heater check the flow and return pipes underneath the vehicle just behind the driver. I can't point you straight to the front heater pipes but would expect them to be traceable under the bonnet.
Chris with BertieB
'96 White unconverted AFT 2.5L Diesel 4WD
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Muzorewa
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Re: Front & Rear Heater Issues

Post by Muzorewa » Thu Jan 14, 2016 3:32 pm

If it's a Bongo you've only recently bought, are you sure the rear heater matrix hasn't been bypassed which is a common mod?
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Gdlee1976
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Re: Front & Rear Heater Issues

Post by Gdlee1976 » Thu Jan 14, 2016 3:35 pm

mikeonb4c wrote:Is there any sign of rust staining / scale in your header tank? If you squeeze the top hose when engine cold, does it feel rigid and/or crunchy as you squeeze it. If either of these apply, its possible the heater matrix has been affected by clogging up. Otherwise, do you have any reason to believe the coolant system might not have been bled properly following coolant refill/replacement? How long has it been like that - did it come on gradually or did it happen suddenly.
Hoses all look & feel good. Water level is good. I just purchased the Bongo a week ago so unsure about coolant changes and the progression of the issue.
Image
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mikeonb4c
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 3:44 pm

Well it has a low coolant alarm, which is good. I wonder if it was fitted before or after a coolant loss episode. Hard to tell about the header tank from the pic - maybe it looks a little rust stained? I wouldn't panic, but I think you should bottom out the problem before driving it all over the UK as there might be a coolant system issue (on which score, an engine block temp gauge might be a worthwhile investment).

Where are you based, in case there's a Bongo specialist near you we can recommend.
Gdlee1976
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Re: Front & Rear Heater Issues

Post by Gdlee1976 » Thu Jan 14, 2016 3:48 pm

mikeonb4c wrote:Well it has a low coolant alarm, which is good. I wonder if it was fitted before or after a coolant loss episode. Hard to tell about the header tank from the pic - maybe it looks a little rust stained? I wouldn't panic, but I think you should bottom out the problem before driving it all over the UK as there might be a coolant system issue (on which score, an engine block temp gauge might be a worthwhile investment).

Where are you based, in case there's a Bongo specialist near you we can recommend.
Swansea Valley
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mikeonb4c
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 4:09 pm

Gdlee1976 wrote:
mikeonb4c wrote:Well it has a low coolant alarm, which is good. I wonder if it was fitted before or after a coolant loss episode. Hard to tell about the header tank from the pic - maybe it looks a little rust stained? I wouldn't panic, but I think you should bottom out the problem before driving it all over the UK as there might be a coolant system issue (on which score, an engine block temp gauge might be a worthwhile investment).

Where are you based, in case there's a Bongo specialist near you we can recommend.
Swansea Valley
Hmmmm, hopefully others can suggest a good local specialist. All I can thinks is that Ed at Celtic Motorhomes (who have one lots of great Bongo conversions in their time) might have someone he can recommend.
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Re: Front & Rear Heater Issues

Post by cmm303 » Thu Jan 14, 2016 4:25 pm

Gdlee1976 wrote:
mikeonb4c wrote:Is there any sign of rust staining / scale in your header tank? If you squeeze the top hose when engine cold, does it feel rigid and/or crunchy as you squeeze it. If either of these apply, its possible the heater matrix has been affected by clogging up. Otherwise, do you have any reason to believe the coolant system might not have been bled properly following coolant refill/replacement? How long has it been like that - did it come on gradually or did it happen suddenly.
Hoses all look & feel good. Water level is good. I just purchased the Bongo a week ago so unsure about coolant changes and the progression of the issue.
Have you been able to confirm that the hoses in and out of the front and back heaters are hot?
Chris with BertieB
'96 White unconverted AFT 2.5L Diesel 4WD
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mikeonb4c
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 4:32 pm

cmm303 wrote:
Gdlee1976 wrote:
mikeonb4c wrote:Is there any sign of rust staining / scale in your header tank? If you squeeze the top hose when engine cold, does it feel rigid and/or crunchy as you squeeze it. If either of these apply, its possible the heater matrix has been affected by clogging up. Otherwise, do you have any reason to believe the coolant system might not have been bled properly following coolant refill/replacement? How long has it been like that - did it come on gradually or did it happen suddenly.
Hoses all look & feel good. Water level is good. I just purchased the Bongo a week ago so unsure about coolant changes and the progression of the issue.
Have you been able to confirm that the hoses in and out of the front and back heaters are hot?
Indeed. If always cold this might give a clue to complete blockage or airlock I guess. Or, if it's partially blocked, I could see hoses getting hot until blower used and supply of hot water then proves insufficient to supply heat to the matrix at the same rate as it is being stripped away by airflow. In that situation the 'out' hose should grow cold after blower switched on, the supply of blown air also growing cold from an initial period of supplying hot air.

Apologies if I'm stating the bleedin' obvious :oops:
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Re: Front & Rear Heater Issues

Post by Gdlee1976 » Thu Jan 14, 2016 6:18 pm

cmm303 wrote:
Gdlee1976 wrote:
mikeonb4c wrote:Is there any sign of rust staining / scale in your header tank? If you squeeze the top hose when engine cold, does it feel rigid and/or crunchy as you squeeze it. If either of these apply, its possible the heater matrix has been affected by clogging up. Otherwise, do you have any reason to believe the coolant system might not have been bled properly following coolant refill/replacement? How long has it been like that - did it come on gradually or did it happen suddenly.
Hoses all look & feel good. Water level is good. I just purchased the Bongo a week ago so unsure about coolant changes and the progression of the issue.
Have you been able to confirm that the hoses in and out of the front and back heaters are hot?
I have not. I looked under there quickly but have not had a chance to have for a close inspection. Honestly I'm not entirely sure what I am looking for but will research and have a look tomorrow.
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Re: Front & Rear Heater Issues

Post by Gdlee1976 » Thu Jan 14, 2016 6:21 pm

mikeonb4c wrote:Apologies if I'm stating the bleedin' obvious :oops:
Believe me, there is NO "bleedin' obvious" with this thing... I'm still learning for sure.
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 6:56 pm

Gdlee1976 wrote:
mikeonb4c wrote:Apologies if I'm stating the bleedin' obvious :oops:
Believe me, there is NO "bleedin' obvious" with this thing... I'm still learning for sure.
I agree. I'd rather not assume, which only risks making an ass out of you and me (Ass-U-Me) 8)
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Re: Front & Rear Heater Issues

Post by Northern Bongolow » Thu Jan 14, 2016 8:55 pm

from the pic you have posted someone has fitted a jubilee clip to pipe that runs from the bottom of the expansion tank to the link pipe to the heater circuit pipe, looks like some ones been in there.

lift the front seats up and post some pics in the engine bay, and a full one of under the bonnet, it may help us.
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Re: Front & Rear Heater Issues

Post by mikeonb4c » Thu Jan 14, 2016 11:37 pm

Northern Bongolow wrote:from the pic you have posted someone has fitted a jubilee clip to pipe that runs from the bottom of the expansion tank to the link pipe to the heater circuit pipe, looks like some ones been in there.

lift the front seats up and post some pics in the engine bay, and a full one of under the bonnet, it may help us.
Well spotted Mr Holmes =D> =D> =D>
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