Foolproof Manual Heater Valve

This replacement heater valve is very simple to make.
First I took the old leaky valve off, and using a hacksaw, cut though it:

Then drill out the hole with a 7/16" drill bit. Thread the hole with a 1/4" NPT tap and fit the parts shown in the photos.

Note: NPT stands for "National Pipe Thread". It is totally different than "regular" bolt threads and is specific to plumbing fixtures. The outside dimension of the pipe nipples is really 1/2", but 1/4" refers to the inside diameter of the pipe. All fittings are 1/4" NPT with teflon tape.

Ed. Note: You should use a barb end where the hose slips on (like the one pictured below).
If you put a hose over a thread, it may leak under pressure.

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~ Foolproof Manual Heater Valve ~

Article by Peter Cummins – Published 2010-06-17

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Member Comments on this Foolproof Manual Heater Valve ↵

Comment by John Baldwin at 2010-06-19 01:27:18

A nice concise article, thank you Peter. I have seen other posts on this forum with similar solutions to this one but with the cable from the dash control attached, back in Jan this year and August last year if my grey matter serves me correctly.

Comment by Peter Cummins at 2010-09-13 20:14:55

Thanks John. I didn't bother with a cable control. It's easy just to turn it on or off before heading out. It's either going to be hot outside or cold, at least in Michigan. In Florida, the heater was never on.

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