Heater Control Valve

[allenhillview]

OK, I've read most but maybe couldn't find all I needed, that given I got to stop heat from coming into cab, via flow we know about already.

Is there a valve that allows by-pass as well so thermostat works as should?

I'll do manual or electric if this is something thats been done? searched sites, see some but would like some input first please?

All I found in threads was to do it if you want, not seen a neat job yet or pics, or any parts used.

 

[allenhillview]

Also, ones I've looked at are vacuum, ( all by-pass mdls.) but the only one i saw that was metal (by-pass mdl. as well) is discontinued from a 50's model chevy.

I guess it will be two valves and a check-valve, plus a tee, if no one pipes in?

Is it true? that the flow can't be stopped on both lines and be done until need heat?
Must it be by-passed?

 

[Cucvnut]

just loop a hose from the in to the out for the heater hoses?

 

[allenhillview]

I'll need to disassemble if heat is needed if I go that way, right?

 

[Keith_J]

What makes you think a simple blocking valve would impact the thermostat performance? Heater circuit bypasses the thermostat.

 

[allenhillview]

It stops flow. How does heater circuit by -pass thermostat?

 

[Keith_J]

The coolant pump is dynamic, not a fixed displacement. So it can be dead headed without issue. The thermostat only blocks flow to the radiator. Coolant still flows through the engine block until the coolant reaches the thermostat's initial opening temperature, then some flow goes through the radiator.

Installing a blocking valve on the heater hose circuit will do no harm. My old truck used such a valve, operated by a Bowden cable, to regulate cab heat. It ran fine in the summer with this valve completely closed.

I suspect you have an issue with the blend door which isn't moving or sealing. The valve on the heater hose is a good substitute, look at LMC Truck for this valve off a 69 Ford, it should fit the existing line.

 

[Motomech]

I just added a simple Ball valve to one of my heater lines. Shut it off for the summer and open it in the winter. I'm about to do it again to a 74 Chevy I just picked up.

 

[allenhillview]

Keith_J, Which hose should I use valve on?

And I read what I wrote from a past thread on here just go to search threads there are 5 on control valve, anyway here we are and thanks.

There is nothing wrong in my box just a little rush of air as you move down the road at 45 or so, stop; then no heat in cab, checked blend door its fine just the fact that the core is hot and fresh air from intake in cowl. Keith which direction is the flow?