Dash air conditioner compressor not running

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Wrinkles

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Feb 5, 2019
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47
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Mn
07 winn.adv. 38t ,put ac oon max air  compressor does not start. Fan blows strong. Checked fuses all okay, any more to check, it would have to be simple as I know zero about ac. Thanks for any ideas

edit by staff - changed subject to make it more descriptive

edit by staff - changed message icon to topic solved
 
I would bet it is low on Freon.  You could have almost any auto shop charge it for you, OR buy a can at Walmart and do it yourself.  A word of caution, if you know nothing about it, I recommend letting others charge it, you can 'overcharge it', and that can cause expensive repairs.  Not unusual at all for a 07 to have leaked enough out that it will not come on, seals get old, and if you don't run the AC occasionally, it is hard on them.
 
If the compressor clutch isn't engaging it could be due to a number of reasons - high pressure, low pressure, problem with the clutch itself, other electrical issue. The engine control module (ECM) could be controlling the clutch operation, that's the way my Jeep works. The powertrain control module (PCM) in the Jeep monitors the various sensors and driver input and does whatever it needs to do.
 
A commonly overlooked failure item, particularly on the Evans Tempcon systems commonly used on motorhomes, is the "Cold Control" fixed temperature thermostat. The control senses when the evaporator is near freezing and shuts down the compressor until the temperature rises again. The control is typically attached to the side of the evaporator housing and has two wires attached with push-on connectors and a capillary tube that's pushed into the evaporator through a small hole. A quick test is to simply unplug the wires and jumper them together with a paperclip. If the compressor then runs normally, that's the culprit. It's an easy part to swap, and usually sells for around $35.
 
Once again thanks to all of you for all the ideas, as I know nothing about ac and would like to use it soon I am going to have it checked out. I will check back with results. You guys are the best
 
Hi all,just a follow up on ac problem. I took it  in they had to replace quite a bit of freon and it works great. They were unable to find any leaks. Thanks for all help, best to you all
 
Wrinkles said:
Hi all,just a follow up on ac problem. I took it  in they had to replace quite a bit of freon and it works great. They were unable to find any leaks. Thanks for all help, best to you all
Glad to hear.  Many will advise against it, but they sell products that stop the leak.  You do have a leak.  A likely culprit is the evaporator core.  Under the dash, royal pain to replace. If they added dye to the system, you can buy a purple light on Ebay, and you will see that dye appears in the AC water droppings under the car.  But honestly, the $50 for a recharge at a shop once a year, I wouldn't complain too much.  Keep cool  :))
 
Sounds like the freon was pretty low. It is something you can add when you notice the AC is not as cold as it should be. It's not hard to do just watch a few UTube videos until you understand what you need to do.
 
The compressor that runs your dash A/C is driven by a pulley and belt from your engine. The shaft behind the pulley has a mechanical seal on it as it enters the compressor to keep the refrigerant in. These seals always leak, they did on commercial compressors which is why most  commercial compressors are now sealed. Not running your air conditioner every month will cause the seal to dry and it will lose refrigerant at a faster rate. Reckon on a top up every 4 years unless you are lucky. If it loses refrigerant quickly, most likely cause is the condenser that normally sits at the front. It is liable to getting a road chip into it damaging the coil. Glad to hear you are now sorted.
 
Spencer and Gizmo thanks for feedback I like the idea of using stopleak and topping off once in a while with small cans , as always thanks is not enough for your help
 
I come from a commercial air conditioning background and it was considered bad practice to use leak stop. The problem is it will not stop a leak from a seal that has a rotary shaft in it. It would be suitable for a pinhole leak in either the evaporator or condenser coils, but to control the refrigerant in the system and make it work there will be either an expansion valve or very small capillary. Any additional restriction in those will stop the AC working correctly. With regard to the filter/drier, this should always be changed when a major component like the compressor is replaced. As someone else has said, if you top the system yourself, you will not know how much is in the system. Too much refrigerant can cause as many problems as too little. In my opinion it is better to let the professionals do any top up. To put it in perspective, even though I have all the necessary equipment, I never bother with doing any of my vehicles, it is not worth it considering the small charge levied.
 
NY_Dutch said:
A commonly overlooked failure item, particularly on the Evans Tempcon systems commonly used on motorhomes, is the "Cold Control" fixed temperature thermostat. The control senses when the evaporator is near freezing and shuts down the compressor until the temperature rises again. The control is typically attached to the side of the evaporator housing and has two wires attached with push-on connectors and a capillary tube that's pushed into the evaporator through a small hole. A quick test is to simply unplug the wires and jumper them together with a paperclip. If the compressor then runs normally, that's the culprit. It's an easy part to swap, and usually sells for around $35.

LOL, it only took me about 2 years to find this issue.  None of the shops could find it.  If a dash A/C is intermittent this could be a prime factor.  I just put a fuse in place of it and the dash A/C has been fine.  I bought one of the replacement sensors just in case.  It looks like a "major" job to get into the evaporator and replace the tube sensor.  I wondered if I could just "wrap" it around the cold side of the inlet hose to the evaporator?

I suspect that unless we get into a very high humidity area it won't matter.



 
taoshum said:
LOL, it only took me about 2 years to find this issue.  None of the shops could find it.  If a dash A/C is intermittent this could be a prime factor.  I just put a fuse in place of it and the dash A/C has been fine.  I bought one of the replacement sensors just in case.  It looks like a "major" job to get into the evaporator and replace the tube sensor.  I wondered if I could just "wrap" it around the cold side of the inlet hose to the evaporator?

I suspect that unless we get into a very high humidity area it won't matter.

There's no need to get into the evaporator housing at all. The capillary tube just gets straightened out so the last ~8 inches is straight so it can be pushed into the small hole in the housing. Pull the old one out and take a look. The hardest part is usually loosening the two thermostat mounting screws. If the Phillips heads strip out, just mount the new thermostat nearby anywhere the capillary tube and wires reach.
 

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