Heater blowing hot on cold setting

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Alanovich
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Joined: 20 Sep 2010 09:33 am
Location: Reading

Heater blowing hot on cold setting

Post by Alanovich » 05 Sep 2011 12:55 pm

The heater on my 360 started blowing constantly hot over the weekend, regardless of what setting I had put the controls to. So it's blowing hot even when on the cold setting, and also with the aircon on.

Obviously there's a fault somewhere, what would the triage approach be on diagnosing a problem like this? Where would I look first, starting with the simplest possible explanation?

:?
7.52pm: I'm jealous. I really wish that I was a) a Fulham fan; and b) at Craven Cottage. What a night for them. The players are still on the pitch, loving it.

http://www.guardian.co.uk/football/2010 ... eague-live

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Chris_C
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Re: Heater blowing hot on cold setting

Post by Chris_C » 05 Sep 2011 01:23 pm

You car is a GLEi from memory... has it got air con?

If not, underneath the heater box in the bonnet (big black plastic thing under windscreen) there is a valve on a water pipe. You can turn it by hand fairly easily, it's most likely the cable that operates this valve thats jumped off. If you turn it by hand you can shut the valve, then if it still blows hot the valve is stuffed. If it blows cold, the cable operating it has gone walkies.

If it has aircon, I've no idea how much of the system is the same!
'89(G) 340 GLE B172k
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast

Alanovich
Posts: 153
Joined: 20 Sep 2010 09:33 am
Location: Reading

Re: Heater blowing hot on cold setting

Post by Alanovich » 05 Sep 2011 02:38 pm

Yes, GLEi and it has aircon!

I'll have a squint later, see if it resembles your description.

Cheers. sm4
7.52pm: I'm jealous. I really wish that I was a) a Fulham fan; and b) at Craven Cottage. What a night for them. The players are still on the pitch, loving it.

http://www.guardian.co.uk/football/2010 ... eague-live

pettaw
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Re: Heater blowing hot on cold setting

Post by pettaw » 09 Sep 2011 02:48 pm

That part of the system is entirely the same, A/C or no A/C. The other possibility is that the cable has jumped off or bent up at the other end, where the lever for adjusting the temperature is. I've seen that a few times too, particularly where the cable has rusted up and some numpty has just forced the lever over with no thought and bent it all up. I hope that's not the case because its a PITA to get to and almost impossible to straighten the cable properly again.

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Chris_C
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Re: Heater blowing hot on cold setting

Post by Chris_C » 09 Sep 2011 03:09 pm

I've bent both the cables on my cars, if you don't look after them or the valve then the force will become too much for the cable.

Silver steel wire plus good forming pliers (not tool box pliers ;) ) and you are going again.
'89(G) 340 GLE B172k
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast

Alanovich
Posts: 153
Joined: 20 Sep 2010 09:33 am
Location: Reading

Re: Heater blowing hot on cold setting

Post by Alanovich » 12 Sep 2011 02:59 pm

This is getting weirder.

Today it's blowing cool on the cold setting, and the aircon being on isn't making it any cooler.

I had a look at that valve on the water pipe, and frankly it all looks and feels pristine.

I think I'll need to get a garage to give it all the once over, including the aircon. :(
7.52pm: I'm jealous. I really wish that I was a) a Fulham fan; and b) at Craven Cottage. What a night for them. The players are still on the pitch, loving it.

http://www.guardian.co.uk/football/2010 ... eague-live

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