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Discussion Starter #1
I have Just brought my new camper project travel 300 miles to get it and in minus 1 found that it is just blowing cold air all the way home brrrr.......


Can anyone shed some light?


 

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1st check the controls work - they should turn with a little resistance.

they are normally ok.

check the bypass valve in the engine compartment, it switches the water flow so that it goes around the cab heater core to get it hot.

it can be checked by connecting a patch cable directly to the valve, if the output pipe then gets warm its an electrical fault (possibly a fuse)

valve problems aren't uncommon.

attached single pdf on bypass valve location plus full heater inventory (composite pdf) which I hope isn't needed.
 

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Discussion Starter #3
Thanks I will try this tomorrow I hope it's not a dash board strip either thanks I let you know if get anywhere
 

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The cable that operates the valve might be broken....ARE YOU SURE YOU HAVE THE BYPASS VALVE IN THE ENGINE BAY,,??? THERE ARE TWO TYPE OF HEATER VALVES, MINE IS IN THE CAB DOWN UNDER THE DASH....
 

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I had a similar problem which was resolved by accessing the cables and manually moving them to allow the warm air to flow.
 

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Thx for your replies, how do manually access cables? & if cable has to be operated manually, what was the long term fix for this?Also, bypass valve is under bonnet I was wandering how I'd create a patch wire to test it?
 

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For cable operated valve you need to remove the center facia/heater panel....un-do the three large nuts behind the control knobs, which just pull off....the heat control cable is the blue one...it might be broken at either end...you can put your hand up under the dash over the steering column and open/close the valve if its easier for you...you need to feel around for the cable/valve....but if you run the engine for a few minutes you'll feel the hot pipes....

If its under the bonnet ,its electrical and there is no heat control cable...
 

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Just if any one is wondering I fixed this problem, the espatcher heater had been removed, they put a hose in its place to link the inlet and outlet pipe together. It had a kink so I cut it and inserted a piece of bent copper to stop the bend kinking and boom perfect heat every time...
 
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