heater blows cold air

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rolesyboy
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heater blows cold air

Post by rolesyboy »

I stripped my heater down. Reverse flushed the matrix . Found no sludge and bolted it back in. Can anybody explain why it blows only cold air. Never used heater before rebuild. Fitted pipe from heater tap to lower matrix input? Not sure if thats a problem ? Thermostat fitted and car has no cooling problems. Is it possible that I have an airlock? If so what steps do I need to take to eliminate this evil phenomena?Cheers. Mark
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IAIN
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Re: heater blows cold air

Post by IAIN »

I have never had problems with an air lock. Check that the pipes in and out are getting hot. If not, check that the on off valve is opening ?

http://www.somerford-mini.co.uk/pdfs/Ca ... les%20.pdf
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Re: heater blows cold air

Post by rolesyboy »

Thanks Iain. The input side seems to be hot but the other side seems to barely get warm. As soon as I put the heater fan on both pipes are cold to touch? I presume this suggests a block but I gave the radiator a good flush both ways for an age and only clean water ran out of it.
To bleed the system I guess I just need to disconnect the hose on the heater tap and run the car till water pushes through?? The odd thing is I have never had to do this before. Cheers
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IAIN
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Re: heater blows cold air

Post by IAIN »

If yor heater matrix is clear I would look at the heater on/off valve. I have seen them blocked, jammed full of crud.
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Re: heater blows cold air

Post by Smiffy »

IAIN wrote:If yor heater matrix is clear I would look at the heater on/off valve. I have seen them blocked, jammed full of crud.
The plunger can also become detached from the control rod, closing the valve.
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Re: heater blows cold air

Post by Andrew1967 »

If the heater valve is working correctly, disconnect the hose from it and blow down the radiator until water comes out of the hose. Reconnect the hose and all should be OK.
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