Renault Clio - Renault clio heater issue

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Fri 10 Oct 2014 16:02
Renault Clio - Renault clio heater issue - joeclio
Hi all,

I have a mk2 clio 03 plate. I recently changed the thermostat as mine imploded. Now I have no heat coming out inside. I drained/refilled/bled the system but to no avail. Now looking to the heater matrix, the lower pipe (inlet) gets red hot but the upper (return) is cold.

Any advice and help would be great
Thanks
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Fri 10 Oct 2014 17:23
Renault Clio - Renault clio heater issue - Falkirk Bairn

Know nothing re Renaults.

However a Civic I had had exactly the same issue - no heat & 1 x pipe hot. It was a sticking valve at the bulkhead where the pipe enters the car. Could turn it with pliers to turn heater on/off.

Fixed with a new valve at my local Indie.

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Fri 10 Oct 2014 21:10
Renault Clio - Renault clio heater issue - Fernando P

There could be a bleed screw on the return flow hose and you need to check that coolant is coming out of it.

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Fri 10 Oct 2014 23:47
Renault Clio - Renault clio heater issue - joeclio
No flow through return hose. Bleed screw out absolutely nothing. Possible block in heater matrix?
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Sun 12 Oct 2014 09:53
Renault Clio - Renault clio heater issue - Peter.N.

Unlikely that it is blocked solid, try disconnecting both hoses and running a hose pipe through it.

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Sun 12 Oct 2014 10:38
Renault Clio - Renault clio heater issue - Fernando P

Keep filling the header tank (with the heater control on hot) until coolant flows out of the return hose. If it does, close the bleed screw when it is running out to avoid getting air in the system. If it does not flow out, you could flush through the heat exchanger as Peter.N. writes above. Also, the heater control valve could be faulty.

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Sun 12 Oct 2014 16:09
Renault Clio - Renault clio heater issue - Peter.N.

If it has a control valve that's most likely the problem - I run the other brand of French cars and they don't.

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