m42 heater pipe connection

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DHFiS
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Post Tue Dec 16, 2014 8:49 pm

Which way round do the water hoses connect to the heater control valve?

I have changed the valve and the heater worked at first but now only blows cold. Her is a pic of it as it is.

Image
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Brianmoooore
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Post Tue Dec 16, 2014 10:25 pm

Your pic. is only 135 x 180, so doesn't show much, but the hose from the back of the head goes to the lower stub, and the one to the upper stub comes from the 'tee' hose.
DHFiS
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Post Wed Dec 17, 2014 8:18 am

Thanks, this link might be a better pic

http://postimg.org/image/i654uh2nl/
Grrrmachine
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Post Wed Dec 17, 2014 9:23 am

Yep, you have the hoses the right way round. Remember that the system needs lots of bleeding, so if the heater blows cold you probably still have air in the system.
DHFiS
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Post Wed Dec 17, 2014 10:36 am

I bled it again at the rad but still no heater. Fixed it by disconnecting the top hose shown in the pic until I could see a stream of coolant then reconnecting it.

I noticed that at idle the flow was barely a trickle but a blip on the throttle and it seemed fine. Is that normal?