Engine air conditioner

[Secarider]

Does any one know what air temp should be coming out of engine ac on max with outside temp at 84. Out of duct

[waiter21]

If you have 84 degree air in, I'd think you should see 64 degree air out.

My old Mirada had an Evans system with a manual water valve.

Verify the water valves is tu shutting the hot water off.

Also consider placing the AC in MAX . This recirculates the inside air.

[SidecarFlip]

20-30 degree temp differential is the norm (measured at a dash outlet. One thing people don't understand is a leaking water valve will severely dergrade AC performance. I would suggest installing a manual valve (WOG Ball valve in the heater hose to shut the flow completely off for warm weather use.

[Iwannacamp]

High blow max cool at highest speed cool cab should be 35-45 outlet temp. You can live at 50, but in hot conditions you prolly won't be happy. It may take 10-15 miles to get that temp in a big cab/car/rv

[Secarider]

I just measured engine air conditioner output temp. Outside temp 80. Rv temp 89. On max output temp was 37 degrees. Then on recirculate it was 39 degrees. I then measured 2015 Silverado temp and output was 33 degrees both measurements taken at duct exit. I was just concerned because this weekend air output while driving behind that greenhouse windshield I couldn't get cold enough. I guess my output in my is ok so no need to take it in to check it out

[Iwannacamp]

37?? You are good to go.

You check your thermometer. Fill a glass with ice and then some cold water. Shake it around drop in your therm and it should get real close to 32 assuming it is calibrated.

[BillMFl]

If your coach has been sitting in the sun and is hot, the dash ac will struggle to cool things down. Way too much volume in the coach to cool. When my coach has been sitting in the sun and is quite hot, I run the gen set and both roof acs long enough to give the dash ac a chance to catch up. Even so, on a really hot day the dash ac will not cool the RV like it does for a much smaller car. After running the roof units until the interior is comfortable the dash ac is cool enough for comfort by itself. But I have seen days when it was so hot and humid the dash ac by itself barely keeps up.

[kenandterry]

I can't really expect the dash air to cool the entire rig. As others have said, when it's hot, you need to run the generator and the rooftop Air Conditioners.

Or.....I installed a curtain rod just behind the front seats and installed a floor to ceiling curtain we can pull closed, then we only have to cool the smaller cockpit.

I only use the side mirrors, so who cares if it's closed up behind us?

[270S]

Answer is straight science - not opinion. A properly running AC will provide a 15-20 degree drop in air temperature from the inlet air. Inlet air is the temperature going over the evaporator. If the ac unit is the "roof top" ac, it is the temp inside your vehicle. If you are talking about an engine ac unit, it depends on whether you are in fresh air mode or recirculation mode. In fresh air mode, it is the OAT (outside air temp). In recirculation mode, it is the temp inside your vehicle. In fresh air mode, the OAT may be higher than you think depending on where the OAT is measured and if you are moving, parked, and what type of surface you are over. Concrete, blacktop, roads, grass, ... all will affect the actual OAT the ac unit "sees".

[325BH]

Something to remember, a car air conditioner is about 5 ton (60,000 BTU). Our camper units are a little over 1.

Car ac compressors operate at a wide range of speeds and output crazy BTUs. They have to cool the car down fast and deal with worse-case thermal situations.

[270S]

Originally Posted by 325BH

Something to remember, a car air conditioner is about 5 ton (60,000 BTU). Our camper units are a little over 1.

Car ac compressors operate at a wide range of speeds and output crazy BTUs. They have to cool the car down fast and deal with worse-case thermal situations.

11,917 BTU/hr equals 1 ton (No need for the history) Rounding that number up makes it a nice, round 12,000 BTU/hr. That's all folks.

[325BH]

Originally Posted by 270S

11,917 BTU/hr equals 1 ton (No need for the history) Rounding that number up makes it a nice, round 12,000 BTU/hr. That's all folks.

Yup. Basically what I said.

[happywhencamping]

My dash AC is wimpy at best. It blows luc warm air on a good. Ford said it was fine. My conclusion( from other comments), your cooling from the engine AC can vary.

I just fire up the gen (It needs something to justify the cost) and run both roof units. It seems to work out so far for us.

One time when the gen quit, it got toasty. Turned out to be loose wires in the transfer switch and one point on the generator.

One item to check out (other than heater hose not being off) if to look for leaks around the box where the evaporator coil is.

[Iwannacamp]

Originally Posted by 325BH

Something to remember, a car air conditioner is about 5 ton (60,000 BTU). Our camper units are a little over 1.

Car ac compressors operate at a wide range of speeds and output crazy BTUs. They have to cool the car down fast and deal with worse-case thermal situations.

You are pretty sharp, but I think the standard auto/p/u a/c then and now is in the 1 1/2 to 3t range and think 3 is pretty unusual.