Resolved Dash A/C not blowing cold air

[Neal]

Brought coach out of storage finally for next trip after 8 months and I don't think the dash A/C is blowing cold air. Recirc etc. Any suggestions in anything I can check? Fuse bay shows all good. 6 years and fine until now. Next Gaffney visit is November.

 

[B52Bombardier1]

Does the AC compressor clutch engage when you turn the system on?

Rick

 

[J&JD]

Were you part of the PDM module Recall? That was one of the known effects of a defective unit.

 

[Webz]

I'm on my 3rd dash AC compressor. As asked earlier, does the clutch engage when turned on?
Do you have gauges to check the freon level? Could be a leak in the system.

 

[Neal]

I had the PDM recall done (twice I think), thanks for the info, I'll put a call in to FL next week.

Where do I find the clutch and what do I do if it's not doing what it's supposed to do?

I do not have the equipment so I'd pretty much have to take it somewhere. I can obviously use the house AC's and I'm scheduled for Gaffney in November so I can get it squared away then. I'm hoping it is just gooked for now somewhere and during some travels ahead it clears itself, or maybe there's a leak. Who knows.

 

[B52Bombardier1]

The AC compressor will have two black hoses sticking out of it and its mounted to the motor with a belt around a pulley on the front. My suspicion is a refrigerant leak and your low pressure cutoff switch is stopping the compressor from engaging - low refrigerant means no oil to the compressor . . . bad.

Don't use sealant in a refrigerant can to fix this!! Sealant contaminates the recovery machines in the professional AC repair shops and those people will DESPISE you. Though, I do recommend the use of UV light dye in the refrigerant to help detect leaks.

Let's hope its not a leaky evaporator or condenser. Maybe just a hose fitting o-ring leak.

Rick

 

[Neal]

Any FL shop can fix this or wait for Gaffney?

 

[Rich W.]

Here’s some interesting reading while you ponder this:

https://newpar.newmarcorp.com/instance1Env99NEWMAR/html/images/SS2013EVEQUILTRAIN.pdf

RV Air Conditioning Service

Servicing your dash air doesn't have to be difficult. In this article we examine how to test, troubleshoot and recharge your RV's air conditioning system.

www.rvtechmag.com

Newmar Dutch Star Diesel Freightliner Chassis Dash A/C

I have a 2000 Dutch Star Motorhome built on a Freightliner Raised Rail Chassis. The Dash A/C does not work. Blows hot air after engine warm up. The Vent function blows Hot air as well. Currently running generator and roof air while traveling. Having trouble getting someone to work on coach. They ...

community.fmca.com

I’m not very familiar with DP dash AC systems but I should be, and your post got me thinking. I’ll be interested to hear your findings on this one. The many links in the third post in the FMCA link are a good resource.

The problem with leak detection is the 40’ run from your dash to the compressor. Also this means that you system takes a lot more refrigerant than conventional automotive systems. But you can see the compressor from the door side rear compartment so the first thing to check is whether or not it is engaging when running and calling for AC. If you are just seeing the pulley spinning but the center part isn’t engaging, you are probably low on refrigerant. The question then would be why which as I said on these things could be difficulty to identidy.

But the charge ports are easy enough to get to (upper pass side corner under the front hood) so you could just start adding refrigerant (up to 5lbs or more) until the compressor comes on (or doesn’t). As I said I’m no expert here but I’ve done a lot of “standard” auto AC recharges. And in most (if not all) cases, ultimately there was a leak involved.

If you decide to try a recharge to see what happens, this is a good little primer on the subject:

https://www.autozone.com/diy/climate-control/how-to-recharge-car-ac

AC compressor (hard to get to but easy to see)

Refrigerant ports (upper passenger side front)

Cheap one-gauge AC charging gizmo (avail at any auto parts store, usually included with purchase of a two 1lb can kit)

If you add 4lbs or so and the compressor starts kicking in, you know it was low, just not exactly why. But if its a really slow leak, that may get you through the season.

 

[Neal]

Great info, thank you.

 

[osuallen]

We had a thermal switch at the evaporator go out this spring that kept the compressor to engage. it also prevented the engine go into high idle -- weird.