Air conditioner compressor delay

[Lakewind]

My 2005 Ranger 3.0 has good air conditioning but it takes 4-5 minutes for the compressor to kick in. It never used to do this. The compressor clutch seems to be working good when it does kick in. Has anyone had this problem with their Ranger? South Carolina summer heat is tough.

 

[sgtsandman]

A/C systems are one of the few things I'll take to a shop since they require specialized equipment to service them properly. It could be that the system is on the fringe of being too low to operate properly, thus the delay. But that is just a guess on my part.

 

[Lakewind]

Thank you. Thats a place to start.

 

[gw33gp]

I have dealt with a somewhat similar issue. I replaced the A/C clutch cycling switch and that solved my problem. I don't know if that will help you, but that switch is not very expensive, and you can replace it without having to remove and replace the freon.

 

[Lakewind]

I have dealt with a somewhat similar issue. I replaced the A/C clutch cycling switch and that solved my problem. I don't know if that will help you, but that switch is not very expensive, and you can replace it without having to remove and replace the freon.

Thank you.

 

[Uncle Gump]

While it could be the clutch cycling switch... you need to remember the pressure temperature relationship of refrigerant. The warmer the ambient temperature... the higher the pressure of the refrigerant in your a/c system.

The clutch cycling switch won't allow the compressor clutch to engage if system pressure is below the upper threshold. That is typically 40 to 45 psi. Then the switch will cycle the compressor clutch off when the system pressure falls below the lower threshold... typically 20 to 25 psi.

So when you start the engine and the compressor clutch won't engage... it could be the system is low and doesn't have enough pressure. As the engine warms up... ambient temps underhood increase... which in turn raises a/c system pressure. If it achieves pressures greater then the upper threshold... the clutch engages.

If that is what is going on in your case... the clutch will cycle on and off fairly quick. The performance of the system will also be degraded and not blow acceptable levels of cold air.

If you try a low pressure switch and it doesn't change your issue... you'll need to put some gauges on the system to further diagnose the condition.

Hope that helps... and good luck.

 

[Lakewind]

Very informative. Thank you.

 

[Lakewind]

While it could be the clutch cycling switch... you need to remember the pressure temperature relationship of refrigerant. The warmer the ambient temperature... the higher the pressure of the refrigerant in your a/c system.

The clutch cycling switch won't allow the compressor clutch to engage if system pressure is below the upper threshold. That is typically 40 to 45 psi. Then the switch will cycle the compressor clutch off when the system pressure falls below the lower threshold... typically 20 to 25 psi.

So when you start the engine and the compressor clutch won't engage... it could be the system is low and doesn't have enough pressure. As the engine warms up... ambient temps underhood increase... which in turn raises a/c system pressure. If it achieves pressures greater then the upper threshold... the clutch engages.

If that is what is going on in your case... the clutch will cycle on and off fairly quick. The performance of the system will also be degraded and not blow acceptable levels of cold air.

If you try a low pressure switch and it doesn't change your issue... you'll need to put some gauges on the system to further diagnose the condition.

Hope that helps... and good luck.

I have a question if you don't mind. When I'm checking the system pressure at 77 degrees ambient temperature with a warm engine and clutch engaged, will the system pressure still be between 40-45 lbs? It's not exactly a/c weather yet. I'm trying to prepare for it.

 

[Uncle Gump]

Ya know... I don't do a ton of A/C work these days... so actual pressure number elude me at the moment. But that seems a bit high. I would think at 77 degrees... the compressor with clutch engaged would pull the system down enough to cycle the clutch off. That number would be below the 45 psi.

 

[Lakewind]

Thanks.