Correct Process To Run AC In Winter?

[OK-944]

Wanting to keep my AC system healthy/lubricated, I'll be running it periodically (five minutes once per week?) throughout the winter - but I have a couple of questions:

One - I heard someplace that I should never run the AC when the outside temps are below 32 f. Is this right?

Two - I also heard someplace that the "proper" way to run the AC in winter (for the purposes of system maintenance) is to set the temp on "max cold," but just long enough to verify that the system indeed blows cold...and then to turn the temp control up to middle/warm - to prevent damage to the system (and also, I suppose, to keep occupants from freezing!). Is this correct?

Three - I've heard that its generally acceptable to run the AC while cabin temp is set to warm for the purpose of helping to mitigate condensation, both in the ventilation system and in the cabin and on the windshield. Is this correct?

And Four - I understand that modern AC systems generally run any time a car's "defrost" circuit is turned on (to dry out the incoming air and to keep the AC system healthy)...but I don't think this happens with our older 944's. Is this correct?

Thanks!

[944 Ecology]

Originally Posted by OK-944

Wanting to keep my AC system healthy/lubricated, I'll be running it periodically (five minutes once per week?) throughout the winter - but I have a couple of questions:

One - I heard someplace that I should never run the AC when the outside temps are below 32 f. Is this right?

Two - I also heard someplace that the "proper" way to run the AC in winter (for the purposes of system maintenance) is to set the temp on "max cold," but just long enough to verify that the system indeed blows cold...and then to turn the temp control up to middle/warm - to prevent damage to the system (and also, I suppose, to keep occupants from freezing!). Is this correct?

Three - I've heard that its generally acceptable to run the AC while cabin temp is set to warm for the purpose of helping to mitigate condensation, both in the ventilation system and in the cabin and on the windshield. Is this correct?

And Four - I understand that modern AC systems generally run any time a car's "defrost" circuit is turned on (to dry out the incoming air and to keep the AC system healthy)...but I don't think this happens with our older 944's. Is this correct?

Thanks!

1) Running it for five minutes at 32F is not going to harm the system.

2) Eh!

3) On the series 2 cars, that's the way the system works.

4) See item 3.

[curtisr]

Turn on the defrost.

[OK-944]

My '87 NA's owners manual says to run the AC "at least once per month" during winter, and to have the temp control set to max cold.

Also - in the section covering the defrost circuit...no mention is made that the AC system is engaged in any way while the defrost is on.

[944 Ecology]

Originally Posted by OK-944

Also - in the section covering the defrost circuit...no mention is made that the AC system is engaged in any way while the defrost is on.

It should be easy to test... push the defrost button and see if the AC compressor clutch is spinning.

[djnolan]

Right now my A/C is not cooling at all even thought the compressor turns on. Since I rarely drive the car and even less frequently use the A/C I conclude the shaft seal got dry and the freon leaked out. So running the A/C monthly makes sense and the part about the temp control on cold is probably to make sure the compressor runs and doesn't get interrupted because the temp control logic thinks A/C is not needed.

Leave the A/C switch on so it gets run on those monthly startups?

Happy Thanksgiving All

[Monkey Wrench]

I think there are refrigerants with a black light sensitive ingredient you can use to troubleshoot leaks.

I dont think you can get freon , It was killing our ozone layer. Instead there are a couple of modern alternatives and others can advise on which is best, better than I can.

you will probably find you need to evacuate the system and really you should not release it , a shop or anyone that works with AC systems can pump it out and contain it safely. you may then need to install the correct filler valve for the correct choice alternative. There is some oil in there too, I've never tried changing the oil. some of it comes with a can of "seal swell" which I used in the same way as the fill bottle. I don't think that will solve all your issues but you can ask about the forum for more solid opinions on that stuff.

I've owned lots of AC equipped cars but any recharge seems to last a month or so at best. I'll throw a can or two in if it's super hot out, but by the time I think of it again that season has passed. I think I simply learned not to need it much here In Vancouver. The crazy new weather patterns may change that, we had the longest and driest stretch I can remember over the last summer.

Happy thanksgiving !, we celebrate ours a lot earlier than in the US. Almost christmas here already now ;-)