TST Cooldown Timer keeping A/C compressor on

[Yo Hoot]

I just got my TST box back from TST.

I had the Turbo Timer upgrade done along with the upgraded program and timing functionality.



After reinstalling it it worked except if the A/C is on when it goes into cooldown, the A/C compressor continues to operate but the cabin heater fan turns off. I do not think its a good idea to be running the compressor without air blowing over the coil.



If the A/C is off when it goes into cooldown, it stays off.



I also noticed my key fob doesn't beep the horn when I lock the doors while in cooldown.



I do have a FASS and I did move the ground.



Anybody else have the same?

 

[Forrest Nearing]

100% same here

 

[Yo Hoot]

Did you talk to TST? Is there a fix coming or is it just the way it is? it seems the cooldown is backfeeding the A/C on signal.

 

[Forrest Nearing]

TST was on the truck when I bought it... so it's "normal" to me



I would guess that the AC compressor and the horn honk circuit are on a circuit that the TST leaves open in order for the truck to stay running... as it isn't hurting anything (though it does take longer to cool down w/ the A/C compressor on) there's no reason to reinvent the wheel to change these non-issues

 

[PToombs]

You could add a relay in the AC circuit so it shuts off with the key.

Just an idea.

 

[Yo Hoot]

Maybe I'm picky but I think if you offer an option then it either should work without doing weird things or at least spell out how it works so we can decide if we want it or not.

I guess I don't like surprises.

I dont think it's a good thing for the A/C compressor to be running without the fan on. Can I do something about it myself? Sure. I'm I supposed to? Maybe TST should give us some direction?

 

[MountainMan1]

Mine does all the same above. But I do recall before installing the TST that when I would lock the doors with engine running with another sentry key the turn signal lights don't flash. I assume the horn probably dosn't blast either; I turned my horn off long ago though.



Peter

 

[Forrest Nearing]

you could just punch the AC button before you shut down

 

[MountainMan1]

you could just punch the AC button before you shut down

That is what I do!



Peter

 

[Yo Hoot]

Oh yea thanks... . I didn't think of that





Seriously, I don't want to worry about the compressor running without the rest of the system up. I'm forgetful. Thanks for all your help



The best suggestion is probably the relay but a better solution yet is a real cooldown unit that works properly.

 

[Forrest Nearing]

if the pressure (due to heat) gets too high, the high pressure switch will disengage the compressor.



I wouldn't worry about it

 

[Yo Hoot]

If the fan stayed on with the compressor I would be less concerned. I would just leave it run if it was on. Since the fan turns off my only real concern is compressor/coil problems. Could the coil freeze without air blowing over it? Could the compressor overheat?

Since it really doesn't run that long it's probably a non-issue but it does warrant the questions.

 

[BDaugherty]

I have a juice with attitude and it keeps the A/C compressor on as well. I just turn it off. Having the compressor running will NOT hurt anything. If the evaporator was to get too cold... and it will... the thermostat will just cycle the compressor off. The reason that I always turn my A/C off during cooldown is that with the heat from the condenser, the cooldown takes longer. With the A/C off, I can be under 300 deg pretty quickly. With the compressor cycling, it can take 2 or 3 times longer to cool off the same amount. I think that it's just the nature of the cooldown timer that keeps the A/C running. All the box does it keep a certain relay engergized in order to keep the engine running. I think keeping the compressor engaged is a side effect more than it is back feeding current. If it bugs you, then do like the guy mentioned before and install a relay. It's just one of those performance trade-offs... and it's worth every penny when the guy at Wal Mart sees your truck turn off with nobody inside it.

 

[Yo Hoot]

and it's worth every penny when the guy at Wal Mart sees your truck turn off with nobody inside it.

That'll never happen... I don't go anywhere near Walmart.

Thanks all for the replies. I'll just live with it. Not really a big deal I guess.