AC Problems. R132 present, Clutch Turning, Hot Air.

[DavidC]

The excessive High Side probably not pulling enough outside air with the hood open. 25 is not a rock hard number, it could be 23,24 etc.. What is the temp at the center outlet in the cab ?. Worst case you may have to bleed some off.

 

[glmoore001]

The excessive High Side probably not pulling enough outside air with the hood open. 25 is not a rock hard number, it could be 23,24 etc.. What is the temp at the center outlet in the cab ?. Worst case you may have to bleed some off.
View attachment 107410

I wound it up to about 1300 rpm and held it there for a few minutes and the temp at the center came down to 63 degrees. It was still falling but very very slowly at that point. This was the first time it had put out any cool air at all. If I can get it to cool, I can give it some time to squeeze out some dye. If I find the dye, I will have the refrigerant recovered then repair the leak and put the correct amount of refrigerant back in. Outside temp at the time showed 88 degrees on the trucks temp display.

 

[DavidC]

Had it on max cool right ?. Looking at the chart at 90 it looks like your in the ball park on temp. On Max that 63 will probably drop a lot more once the inside air cools down some especially when driving.

Dave

 

[glmoore001]

Had it on max cool right ?. Looking at the chart at 90 it looks like your in the ball park on temp. On Max that 63 will probably drop a lot more once the inside air cools down some especially when driving.

Dave

It came down to 60 degrees, no further. Release some refrigerant, or add some refrigerent?

 

[Wayne M.]

It came down to 60 degrees, no further. Release some refrigerant, or add some refrigerent?

What's your ambient conditions? Do you have it on recirc? Is this idling in the driveway? Will it chill down better on the hiway?

 

[DavidC]

What's your ambient conditions? Do you have it on recirc? Is this idling in the driveway? Will it chill down better on the hiway?

Pressure readings also

Dave

 

[glmoore001]

What's your ambient conditions? Do you have it on recirc? Is this idling in the driveway? Will it chill down better on the hiway?

I went for a 10 mile drive to get the above answers this evening. about half that was above 65 mph with Max AC running.
Center vent temp ranged 60 - 64 degrees.
Ambient temp 94 degrees

I hooked up hoses as soon as I arrived back home
Idling in the driveway

Static pressures Low= 90 High = 95
System on Max Cool Low = 25 High= 300 and climbing
Is there a button for recirculate on 2nd Gen? I could not find one.
I had it on Max AC the entire time.

Thanks for the response and all the help. Gary

 

[Wayne M.]

I think you might actually need another can.

 

[DavidC]

Max AC is recirc. on second gens, no seperate button. Is the compressor cycling ?

Dave

 

[Wayne M.]

Max AC is recirc. on second gens, no seperate button. Is the compressor cycling ?

Dave

I think with 95* outside, and a warm underhood, he should be past 350 on the high.
I wonder how well the blend door is working?

 

[DavidC]

I think with 95* outside, and a warm underhood, he should be past 350 on the high.
I wonder how well the blend door is working?

Yeah the blend door has crossed my mind. I think my coupler is cracked on mine and it is a PIA to get to, pullung back the carpet and cutting up the floor insulation. I agree it may still be a little low on freon.

Dave

 

[DavidC]

Maybe cutting the heat would verify blend door.

Dave

 

[glmoore001]

Ok, I will add a little refrigerant. I think I might easily hit that 350 mark if I wait with the hoses attached. The pressures on the high side tick up about 5 lbs. every couple seconds.
Yes, the compressor is running. I have yet to see it kick off while testing pressures or just generally watching it run..
Does the blend door admit/block outside air?

 

[Wayne M.]

The blend door is hooked up to the hot/cold dial, or temp control. It either blocks or directs air past the heater core. I don’t think 2gens have water valves to shut off coolant to the heater core, so that will be hot all the time the coolant is hot. The blend door has to do its job. There is another door that allows outside air from the cowl in. That will close on recirc or max. Usually when that happens you’ll hear the blower motor get louder inside the cab, because it’s sucking air from the floor, and not from outside.
Regarding the hi side pressure, that can be artificially high due to a hot condenser. Either by being blocked with dirt, or not being able to pass air due to mashed fins, or the cooling fan not clutching (this is a big problem on 3 gens). This is why I asked if it cools better on the hiway.
Another question- While running the system during the hot humid days, does it make condensate water? You know, from the drain on the lower firewall? Like all cars do?

 

[DavidC]

There are no valves to shut off the water unless you do what some have done by installing them to get cooler air. Step # 8 talks about clamping the hoses ( C clamps etc. ) there are/were some threads on that around here. Very humid air will cut the efficiency of the AC. If hot enough the clutch may not cycle unless the low or high pressure switch is activated.

Dave

 

[DavidC]

When adding more freon keep a close eye on vent temp.. I have over charged mine before and while driving I heard a very distinct bang. That bang was the high pressure blow off valve on the compressor opening which released freon. After that I had to add some back as it dumped to much. Just a FYI.

Dave

 

[fest3er]

When adding more freon keep a close eye on vent temp.. I have over charged mine before and while driving I heard a very distinct bang. That bang was the high pressure blow off valve on the compressor opening which released freon. ...

That happened to me once when I jumpered the high-pressure switch connector (hey, hold my beer while I try this). It was a *very* loud, unexpected buzzing noise. I'll always remember never to do *that* again.

 

[glmoore001]

That happened to me once when I jumpered the high-pressure switch connector (hey, hold my beer while I try this). It was a *very* loud, unexpected buzzing noise. I'll always remember never to do *that* again.

Well, I did not get the expected results. I started it in the driveway this time, hooked up the hoses and added about a half a can when I noticed I could not get center vent under 74 degrees. I did not put in the rest of the can. I ran it up to 1500 rpm for about 5 minutes and the temp never got below 74 at the center vent. Outside temp was 94 degrees running full fan on Max AC.
Pressures were 105 and 110 static
27 and 350 running.
Never saw the compressor cycle off, ran constantly.
Just so you know.. I was getting lots of condensate running from the drain yesterday, not so much today.
Thanks.. Gary

 

[DavidC]

Gary, What State are you located ?. Off hand it appears over charged. You could try bleeding back to where you were unless some body has a better idea. Starting to wonder if it was slightly over then. As I stated earlier R134 is very finicky with over/under charging.

Dave

 

[DavidC]