A/C not blowing below 60*

[CJ7365]

When you added more 134, what were your pressure readings?

Was the compressor cycling?

When temps are above 80, my compressor does not cycle off, it stays on

If you can get to it try putting the thermometer right on the evaporator and see what the temperature is there


Your prior pressure readings still seem low

[Old Scout]

Pressure readings still low--could be the compressor---at the risk of repeating---max temp differential between incoming ambient air and vent is 20-25 degrees. Bad expansion valve would tend to raise pressure not lower it. Not sure what input you are looking for now??????

[mel s]

Originally Posted by racerb

Have a Cross Country DP checked out the A/C can not get it below 60* at the dash.
Took the Evens water control out of the system installed manual valve. Evaced the system installed 3# 134a coolant low side reading 20# high side 185-205
Still not getting below 60* at the dash.
Cycling off at 19# on at 32#
Can live with it but its not right
Help

racerb
What temp is the incoming air?
The "output air temperature" is dependent on the "temperature of the incoming air".
Not much more than a temperature difference between the incoming and output air than 20 degrees F can be expected from any air conditioner.
See: http://contractingbusiness.com/rob-d...lta-difference
Mel
'96 Safari

[wa8yxm]

Normal low side is higher than that.. I do not know normal high side but it appears you are a touch low.

Also if it's 90 in the shade, 60 would be known as FANTASTIC performance, 70 would be acceptable. (or less)

[racerb]

What I am wondering if the expansion valve is stuck in say the middle would it work as a thermostat holding it at 60* never ran into that before just trying to figure if it doing all it can really looks like a small system for the Motorhome
Thanks for all the input.

[Ray,IN]

I think your refrigerant charge is too low. Remember, the compressor is mounted to the engine, it takes more refrigerant to reach the proper amount than a front engine.
I use a simple gauge on a large can of refrigerant from WalMart to refill my vehicles. When the needle gets into the green it's full. More is NOT better with the new refrigerants, unlike the old R12, which was not as picky.

[TQ60]

If compressor cycling then could be sucking low or the sensor in evaporator in the cold spot.

Placement of the sensor that controls system makes a difference.

Look for a long tube about 1/8 inch diameter going into unit.

If too close to expansion valve it gets cold fast before rest and shuts off the cooling.

[racerb]

Originally Posted by TQ60

If compressor cycling then could be sucking low or the sensor in evaporator in the cold spot.

Placement of the sensor that controls system makes a difference.

Look for a long tube about 1/8 inch diameter going into unit.

If too close to expansion valve it gets cold fast before rest and shuts off the cooling.

Had replaced the sensor it was bad back in the factory location
60oz. of coolant it is close to the expansion valve may try pulling it out to see if it makes a difference

[Scatterbrain]

Are you running the coach air to cool the cabin down first? Personally I drive with the coach air and dash air on. With only the dash air on you won't get very cold because the rest of the cab will just keep heating up. As has been pointed out, you are looking for a temperature differential, not an absolute temperature. If your incoming air was 90* and the outside air was even hotter then I'd say 60* was perfectly adequate. Bot the incoming air (what's being blown across the evaporator and into the cabin) and the outside ambient air (what is being used to cool the condenser) matter. The general target difference is 20* - 25*. It sounds like you're getting more than that.

[racerb]

Thanks every one that commented I am just going to be happy with what I have pulling 25*+ difference and they will run the overhead air on hot days.
Final results
Evap the system put in 60 oz (3.75#) of fresh 134a coolant. still maybe a little low but with the Mfg. calling for 2.5# not wanting to over do it.
replaced the sensor switch.
replaced evens electric water control valve with manual shut off heater valve
checked the condenser, condenser fan, compressor, belts and hose's all like new.
the only thing I didn't do was replace the expansion valve may try that later.
This unit is 11 years old with 6000 miles customer says the A/C has never worked the way it should cools for a while then warns up I am thinking that was the result of the Even installed water shut of valve that they admit to being faulty and have a replacement for at customer cost and low coolant Evens calls for 2.5 oz of 134a.
Thanks again they will take it for a trip and we will see how it goes going the be over 103 this weekend should be a good test of both air conditioners

[mel s]

Originally Posted by racerb

Thanks every one that commented I am just going to be happy with what I have pulling 25*+ difference.

racerb

You can not expect, (and will never get), better than a 25 degree ΔT, (Delta T), from you A/C.
Mel
'96 Safari

[racerb]

Originally Posted by mel s

racerb

You can not expect, (and will never get), better than a 25 degree ΔT, (Delta T), from you A/C.
Mel
'96 Safari

The unit will pull down the longer you run it as the inside of the M/H cools can get it from high 80's to into the 50' after it runs for a while.

[Deny]

Check the temp on your other vehicles, for comparison

You might be getting all you will get.

[wa8yxm]

You said it won't below less than 60 Degrees. You also said ambient was 95.. What is the intake temp (Temp inside the RV)

If the cabin temp is 90 and the outside temp is 95, and the discharge temp is 60, that is called "Working as designed". .