MG MG ZR (2001 - 2005) - 05 1.4 heater always cold

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Tue 16 Dec 2008 22:00
05 1.4 heater always cold - martynmgzr
hello, my heater is always cold i had a new thermostat put on thinkin that was the problem but it still isnt workin any ideas its freezin inside my car write back

Edited by Dynamic Dave on 16/12/2008 at 23:29

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Tue 16 Dec 2008 23:27
05 1.4 heater allways cold - Javalin
Was the coolant system fully bled when the thermostat was fitted? Could be an air-lock to the cabin heat exchanger.

Easy to cure. Start the car and let it warm up a bit, either (a) if fitted there might be a bleed nipple in the hoses to the cabin or (b) massage the hoses to the cabin with the engine running.

You'll feel them go very hot when the air is out. Let the engine cool and then top up coolant if required.

Else - I guess it could be a fault with the heat exchanger controls.

I assume there is enough coolant in it? I.e. no leaks?

james
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Wed 17 Dec 2008 21:15
05 1.4 heater allways cold - martynmgzr
hi no iv got no leaks and the controls are working in the car from where the water goes into the car heating its cold but its running fine around the engine keeping everything cool so it doesnt over heat its just the pipes to the car heating thats cold :{ dnt under stand it does that help abit more info write back
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Thu 18 Dec 2008 11:02
05 1.4 heater allways cold - piston power
There is two pipes to the heater flow and return is any hot?

If one is hot and the other is cool it could be blocked or air locked.

You can remove both pipes and flush the matrix out with hose pipe.

Does you car have a heater valve fitted maybe faulty not allowing flow.

More information required from you please???
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Thu 18 Dec 2008 21:44
05 1.4 heater allways cold - martynmgzr
both pipes are cold its not the valve i have taken it off and made the system run with out it and still no heat, i only get a little bit of heat if i realy boot my car up the motorway but its not much is there two pipes goin in and two coming out?????????
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Thu 18 Dec 2008 22:50
05 1.4 heater allways cold - rtj70
If you posted in English with punctuation and capitals you might find more members actually read your posts. Just a thought...

Rob
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Fri 27 May 2011 23:59
05 1.4 heater allways cold - DAM1

Hi - late in the day and not many of these cars around! - but - on these ZR's there's an overheat/over pressurised blow-off cromet located within a plastic gismo located across the supply/return pipes to the heater matrix just before they go through the bulkhead. If you study the pipe layout they don't make much sense until you relaise that the gismo provides a short cut from block to radiator and if the gromet within blows out then the path of least resistance, flow wise, starves the heater matrix - hence no heat.

The probable cause is failure of the thermostat (hopefullt the head gasket hasn't been breached). Take of the themostat and poke about, the small black gromet (about 10mm diametre) should be at the mouth of the thermostat housing. Removing it doesn't solve the problem !!. a new gisom is required or alternatively remove it and insert a 20mm copper Yorkshire elbow and a 20mm copper striaght to gaurantee flow to the heater matrix!! - cheap and nasty but it got me going - no more steamed up windscreen.

Regards

David

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