free hit
counters
Dodgy HeatingI know this is not strictly speaking an electrics problem but is seemed the best place to put the Q. I have started work on my Excel now - Interior/Exterior/Lights/Glass/ICE/HVAC & Other - The Lotus Forums Jump to content
dermotbell@onetel.com

Dodgy HeatingI know this is not strictly speaking an electrics problem but is seemed the best place to put the Q. I have started work on my Excel now

Recommended Posts

Hi

I have started work on my Excel now that my dear old Elite has been sold. The first problem I am tackling is the heating system (non air-con 84 model):

1. The fan switch does nothing in either of the speed 1 slots but does in speed 2.

2. I think the heat control is working but difficult to tell as so little air comes out any vent. I have taken off the centre panel wood veneer thing and both rotary dials move the cable. I have removed some other bits of trim to see the contral plate on the RHS of the heater unit but altho' I can see the water pipes and the switch thingy I still can't see the control plate. So I am guessing that I will have to remove the entire front fascia to get access?

3. I did originally find that the inlet manifold pipe was disconnected and I have rectified this which sorted some rough running at idle (just as it did on my M100), so there is an air feed to the reservoir. Now assuming that if I can see the cables working at the rotary switch and they are still connected at the control plate it seemed that a vacuum issue was the most likely cause (i.e. one of the internal reservoirs or switches) but as the footwell/windscreen is mechanical I have gone back to a mechanical cable issue as the likely cause.

Any thoughts??

Thanks

Dermot

Share this post


Link to post
Share on other sites

Upgrade today to remove Google ads and support TLF.

Hi Dermot,

If you remove your fan switch, i presume its the same as the old esprit ones!if you open it up you will find that one of the contacts will of snapped off hence it just works on the second speed, just sorce a new switch and it will be fine, As for your heating im not familiar with the set up so would just be stabbing in the dark..

Regards danny

Share this post


Link to post
Share on other sites

Thanks Danny, that sounds reasonable.

I have gotten enough trim out to see the control panel and I can see the wire moving the lever as it should and I can see the valves been opened and closed, and certainly the fascia vents in the centre panel are being supplied as I can see the panel move up and down as it should so there would not appear to be a vacuum problem there at least. What I can't tell is if the re-circ/fresh air flap is moving and whether the mechanical screen/footwell flap is moving.

Either way with fan on 2, blowing hard and the centre console flap open I can barely feel any air at all. (BTW the temp control works as I can feel the difference between hot and cold air). I can't see any position of a flap (even if stuck in an odd position) that wouldn't allow air to come out somewhere, even if it were just thro' the side fascia vents.

My only conclusion can be that there must be a physical blockage either before the fans or immediately after them. If so, this is quite depressing as the whole lot would have to be stripped out.:)

Dermot

Edited by dermotbell

Share this post


Link to post
Share on other sites

What are the condition of the corrugated tubes that supply the air into the vents? It's very easy for them to either collapse or unattach. Either way it's not too bad if this is the cause.

Share this post


Link to post
Share on other sites

Mat, the tubes seem ok, but that wouldn't explain why, with the centre fascia flap open, I get very little air flow.

On some further investigation I think the flap that determines re-circ/ fresh air isn't working. I have some skinned knuckles but I think this flap is stationary, closing the fresh air inlets. It's difficult to be sure as it's a very tight squeeze to get your fingers in the 2 apertures (and I have no young kids to abuse with this job), but I still don't understand why this would make re-circ air so weak.

I have removed a side fascia vent hose from the heater unit and have found that no matter what the position of the air distribution rotary dial I can feel no air coming out here. My understanding is that no matter what the position of the dial you should always be able to get air from these 2 vents.

Could it be blockage?

This is one of those jobs that is mushrooming in terms of what I might have to strip out just to see the problem.

Dermot

Ok

So I skinned a few more mil of my knuckles and can now testify that the re-circ/ fresh air flap is working. Now even if the mechanical screen/footwell is not I can only conclude that there is a blockage.

Does anyone know if there is a way to test the individual fans on the heater (i.e. isolate power separately to prove serviceability)?

Blockage is very depressing, but unsure how this would happen as wire mesh over sir intakes was in place on car.

Dermot

Ok so latest is I have used an old coat hanger and poked thro the 2 vents at the side of the unit and there was no blockage in either. I also stuck it down the 2 fresh air apertures at the bonnet and there was no blockage there.

What I have discovered is that only one of the fans is working, so it looks like the whole unit will have to come out any way.:)

Dermot

Edited by dermotbell

Share this post


Link to post
Share on other sites

I dont know if this is related, I'm stripping the dash out of my 2.2 elite and have discovered a sizeable pile of rust in the top of the heater box, it seems that there was a steel closing plate across the top of the heater matrix. Could be you have a similar issue?

Mark

Share this post


Link to post
Share on other sites

It's possible Mark as there are 2 flaps at the intake apertures which are foam padded onto something?

I won't know until I get it out.

Dermot

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×