Winter Projects

[phoemsen]

Decided to tackle a couple of issues. The vacuum line to the hot water valve needed replacing, so I ran a new one back to the "Heater Vacuum Disc" switch mounted on the temperature controller. The actuator for the "Heater/Evaporator" door has a broken vacuum connection, so I ordered a new one from Old Air.It will be interesting to see if these components function as they should after the repairs. How reliable are the old vacuum controls for our HVAC systems?

There are many more important things that require attention on my car, but this seemed like a nice place to start. I had forgotten how difficult it was to wriggle my way under the dash and fish in new vacuum lines!

It's going to be a long, cold winter up here in Saskatchewan, I hope I put up enough firewood  to last!

[1965rivgs]

Hi Peter,

  Just an FYI...the component in the pic you posted, with the broken vacuum nipple, is the diaphram which controls the air flow thru the dash vents.

  Tom

[phoemsen]

Thanks,Tom. In the bible, they refer to it as the "Heater-Air conditioner diaphragm". But you're right, it diverts the air from either the evaporator core, through the vents, or across the heater core, in conjunction with the "Heater temperature door".  I was wondering about the reliability of the vacuum system itself. The 2 "plugs" that connect to the temperature controller seem pliable and soft, which should mean a good flow of vacuum. But, as we know, any minor leak will prevent the devices from working as they should. It must be a good systrem, I do not recall a lot of comments as to troubleshooting etc. As I get farther into this ( my A/C has not been re-charged yet) I am also wondering about replacing the STV? If it is working, I will keep it, the alternative seems to be replacing it with an ON-OFF device rather than modulating the temperature.

[lrlforfun]

OK: I purchased both actuators from old air. Replace the vacuum hoses and if the system holds refrigerant ......wa la!  Mitch