Heater Control Valve

[Ed P.]

I have 2 heater control valves. Looking at them with the copper tubing pointing down, on top there is, on one of them a small square box about 1/2" square with a copper wire coming out of it. The copper wire leads to one end being all curled up.
Which one is correct ? And what is the copper wire for and is it needed ?

Please
edd

[Harry S.]

Re: Heater Control Valve

What year car?

[Larry M.]

Re: Heater Control Valve

Sounds like the one with the copper tubing coiled end is an air conditioning refrigerant expansion valve. Not sure about the other. Need year of car(s), more complete description, and/or pictures.

Larry

[Frank D.]

Re: Heater Control Valve

Is it copper wire or copper tubing? If tubing then it may well be the "capillary" tube. This was used for fine grain feedback control of the heater valve (definitely on C1s - not so sure about C2s). the bulbous end of the tube was stuck down in the heater box near the heater core. They never worked worth a damn and repro heater valves don't have them. You can 'fake it' and attach the tube to a repro valve and stuff it in the heater box for originality if desired but its a totally unnecessary part of the valve.

[Ed P.]

Re: Heater Control Valve

Thank u Thank u very much

I am not gona use the one with the copper wire.

My car is not for judging, i want a driver

EDD

[Richard M.]

Re: Heater Control Valve

Frank's correct. For some reason the originators thought it was a good idea to use the capillary as a way to close the valve if the temperature got too hot. Maybe a safety issue. To me it was clearly a overthought and unnecessary part. It may have been a ex-Jaguar Engineer that came up with it, prone to adding parts to assemblies that were not needed just to make it appear more complex.

I did some experiments a few years ago, being Mr. Curious as I am.

Here you can see a original valve I removed from a '60 heater box. Note the part number stamped on the flange. It's 3139127. FYI the part number is covered once the valve is installed.
P7140005.jpgP7140009.jpg

This is ambient temperature. Valve closed.
P7140006.jpg


This is with the valve open via the manual on-off lever. You can see the plunger.
P7140007.jpgP7140008.jpg

I heated the capillary tube and it expanded the plunger outward. That then moves that U shaped bracket with the adjustment screw which is attached to the valve mechanism. Even with the manual lever open, the lever being pushed by the plunger closes the valve.
P7140010.jpgP7140011.jpg

But for judged cars, it is expected to see the tube assembly as it exits the valve and disappears into the core box. I do not believe it's functionality is tested, as most people don't know how it works.

Rich
===
p.s. Ed used the "61/62" icon in his post which is tricky to notice sometimes.

[Ed P.]

Re: Heater Control Valve

thank u Rich,