f-two-fiddy
Registered User
So, I have the valve in hand, and was wondering if there is a vacuum source that works on normal AC. Not just Max AC. I'd like to have the heater core bypassed any time AC is selected.
Heater Core Bypass Valve
- Thread starter f-two-fiddy
- Start date
Sounds like an electrical bypass valve would have been ideal... relay it off the compressor signal.
Otherwise, there isn't a vacuum source that's active on "normal" AC, just "max" to recirculate and close the fresh air intake.
Otherwise, there isn't a vacuum source that's active on "normal" AC, just "max" to recirculate and close the fresh air intake.
I don't know of a vacuum source that would apply vacuum in AC and in MAX AC but not at any other time.
I haven't done it yet, but I had the idea of installing a vacuum switch on the temperature blend selector arm, so that when the arm's all the way in the "Cold" direction, vacuum would be applied to that line and the bypass valve was actuated. I don't know how practical it would be, but I agree that that would be better than only having the valve close when the system's set to MAX AC.
Failing that, an electric valve tied to the compressor power line (before the compressor cycling switch) would be the best way to get the result you want, although there's one problem there that may complicate things...the compressor's activated when the system's set to DEFROST. You want the compressor cycling in DEFROST mode; it helps to dry the air before going through the heater core. But, obviously, you also want heat.
I haven't done it yet, but I had the idea of installing a vacuum switch on the temperature blend selector arm, so that when the arm's all the way in the "Cold" direction, vacuum would be applied to that line and the bypass valve was actuated. I don't know how practical it would be, but I agree that that would be better than only having the valve close when the system's set to MAX AC.
Failing that, an electric valve tied to the compressor power line (before the compressor cycling switch) would be the best way to get the result you want, although there's one problem there that may complicate things...the compressor's activated when the system's set to DEFROST. You want the compressor cycling in DEFROST mode; it helps to dry the air before going through the heater core. But, obviously, you also want heat.
Ah dang, good catch on that... scratch the electrical one.
I just used a manual ball valve on my 09. Older Dodge trucks used a cable driven bypass... maybe that could be rigged up
I just used a manual ball valve on my 09. Older Dodge trucks used a cable driven bypass... maybe that could be rigged up
79jasper
Chickenhawk
It would take some figuring. But seems like there would be a way to tap into the blend door. Where when the temp is on cold, it'll close it.
Sent from my SAMSUNG-SM-G935A using Tapatalk
Sent from my SAMSUNG-SM-G935A using Tapatalk
I have that on my 86. T off of the vacuum actuator under the hood PS, over the HVAC housing. You can use a single line like this http://www.rockauto.com/en/catalog/ford,1980,pinto,2.3l+140cid+l4,1135268,heat+&+air+conditioning,heater+valve,6860.
I have the 4-port heater valve on mine but forgot what the part number is.
Rick
I have the 4-port heater valve on mine but forgot what the part number is.
Rick
