Ac hot when first starting
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Ac hot when first starting
2017 Lariat 4wd crew cab
I first start my truck it only blows hot air with AC on. Only starts blowing cold after I start moving the truck. I know this is a symptom of a bad condenser fan. I can't seem to locate a condenser fan. Is it possibly the fan clutch? Truck doesn't overheat at idle.
I first start my truck it only blows hot air with AC on. Only starts blowing cold after I start moving the truck. I know this is a symptom of a bad condenser fan. I can't seem to locate a condenser fan. Is it possibly the fan clutch? Truck doesn't overheat at idle.
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It is the fan clutch. You mean that if you just let it sit and idle with the A/C on for a minute or so, it will not blow cold air? And if you sit in traffic for a minute or so, it starts to blow hot again until you get moving? Any icing on the suction line out of the evaporator?
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It is the fan clutch. You mean that if you just let it sit and idle with the A/C on for a minute or so, it will not blow cold air? And if you sit in traffic for a minute or so, it starts to blow hot again until you get moving? Any icing on the suction line out of the evaporator?
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No freezing. Have had refrigerant vacand refilled 3 times and it has never been low. It is a diesel but not sure on aux heat. It is a lariat with auto climate and dual control.
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The fault has to be in the blend door. If, as you describe, the system will blow cold once it starts working even if you let it idle for an hour, then it can't be air flow through the condenser. With no freezing on the suction side and that you've had it serviced multiple times means the system itself is up to snuff.
Why does it behave they way you describe? Again, look to the blend door. But I have no idea why it would behave that way. Funny that it wouldn't move until you start driving. Could be a vacuum control issue that's not moving the door properly. You might also take a peek at the compressor clutch when you first start the vehicle. If that's not turning at first start then there's something screwy in the body control module not turning on the compressor. But that would mean something in the computer code and that would be really goofy since it would be in other computers. But just check to rule it out.
Why does it behave they way you describe? Again, look to the blend door. But I have no idea why it would behave that way. Funny that it wouldn't move until you start driving. Could be a vacuum control issue that's not moving the door properly. You might also take a peek at the compressor clutch when you first start the vehicle. If that's not turning at first start then there's something screwy in the body control module not turning on the compressor. But that would mean something in the computer code and that would be really goofy since it would be in other computers. But just check to rule it out.
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The fault has to be in the blend door. If, as you describe, the system will blow cold once it starts working even if you let it idle for an hour, then it can't be air flow through the condenser. With no freezing on the suction side and that you've had it serviced multiple times means the system itself is up to snuff.
Why does it behave they way you describe? Again, look to the blend door. But I have no idea why it would behave that way. Funny that it wouldn't move until you start driving. Could be a vacuum control issue that's not moving the door properly. You might also take a peek at the compressor clutch when you first start the vehicle. If that's not turning at first start then there's something screwy in the body control module not turning on the compressor. But that would mean something in the computer code and that would be really goofy since it would be in other computers. But just check to rule it out.
Why does it behave they way you describe? Again, look to the blend door. But I have no idea why it would behave that way. Funny that it wouldn't move until you start driving. Could be a vacuum control issue that's not moving the door properly. You might also take a peek at the compressor clutch when you first start the vehicle. If that's not turning at first start then there's something screwy in the body control module not turning on the compressor. But that would mean something in the computer code and that would be really goofy since it would be in other computers. But just check to rule it out.
Also, when truck is sitting still with the AC on there is no condensation dripping. Used to leave a pretty good pool underneath it.
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It is an electric fan clutch. If this is a gasser, it might also have a small electric auxiliary fan. I don't know if that is absolutely true in every configuration. A/C evaporator condensation dripping is affected by temperature, humidity, fan speed, and refrigerant flow through the evaporator. The drain line could also be plugged. Who knows, really.
If you want to test your fan theory, do this; Put a thermometer in the HVAC vent, open the hood and put the vehicle in the failure mode, which I believe for you is where you first start the engine with the A/C on for a couple minutes. You get no A/C cooling in this mode, correct? Now, using your most excellent garden hose and nozzle, spray water onto the condenser. If your fan theory is correct, the water will very efficiently cool the condenser and dramatically drop your HVAC vent temperature.
You could also put a set of gauges on the system. If the condenser isn't extracting heat, head pressure will be high.
If you want to test your fan theory, do this; Put a thermometer in the HVAC vent, open the hood and put the vehicle in the failure mode, which I believe for you is where you first start the engine with the A/C on for a couple minutes. You get no A/C cooling in this mode, correct? Now, using your most excellent garden hose and nozzle, spray water onto the condenser. If your fan theory is correct, the water will very efficiently cool the condenser and dramatically drop your HVAC vent temperature.
You could also put a set of gauges on the system. If the condenser isn't extracting heat, head pressure will be high.
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It is an electric fan clutch. If this is a gasser, it might also have a small electric auxiliary fan. I don't know if that is absolutely true in every configuration. A/C evaporator condensation dripping is affected by temperature, humidity, fan speed, and refrigerant flow through the evaporator. The drain line could also be plugged. Who knows, really.
If you want to test your fan theory, do this; Put a thermometer in the HVAC vent, open the hood and put the vehicle in the failure mode, which I believe for you is where you first start the engine with the A/C on for a couple minutes. You get no A/C cooling in this mode, correct? Now, using your most excellent garden hose and nozzle, spray water onto the condenser. If your fan theory is correct, the water will very efficiently cool the condenser and dramatically drop your HVAC vent temperature.
You could also put a set of gauges on the system. If the condenser isn't extracting heat, head pressure will be high.
If you want to test your fan theory, do this; Put a thermometer in the HVAC vent, open the hood and put the vehicle in the failure mode, which I believe for you is where you first start the engine with the A/C on for a couple minutes. You get no A/C cooling in this mode, correct? Now, using your most excellent garden hose and nozzle, spray water onto the condenser. If your fan theory is correct, the water will very efficiently cool the condenser and dramatically drop your HVAC vent temperature.
You could also put a set of gauges on the system. If the condenser isn't extracting heat, head pressure will be high.
Fleet Mechanic
Joined: Aug 2017
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From: St Louis Suburbs
My 2017 PSD did this same thing. It only got cool after driving. If I then had to idle for several minutes (like in bad traffic) it would get warm again. My engine was getting into the red zone when towing also.
It was my fan clutch. About $1,200 to fix. I was out of my 36,000 mile warranty by 3,000 miles. Ford picked up $900 of the repair for me.
It was my fan clutch. About $1,200 to fix. I was out of my 36,000 mile warranty by 3,000 miles. Ford picked up $900 of the repair for me.
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Definitely want to check this. have ordered a new one just to plug in. Problem is I can't figure out where it plugs in. Doesn't appear to be the same as the 2016 and prior. Any idea where the connector is for the sensor? I know the sensors behind the dash but the connector should be out front somewhere.
Also, I ran water over the condenser and that didn't change anything so I don't think it is the fan clutch. Has been working perfectly now for the fourth day in 110+ heat. can'treally test anything until can get it to malfunction again. It must think it is at the dealer LOL
Also, I ran water over the condenser and that didn't change anything so I don't think it is the fan clutch. Has been working perfectly now for the fourth day in 110+ heat. can'treally test anything until can get it to malfunction again. It must think it is at the dealer LOL
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Definitely want to check this. have ordered a new one just to plug in. Problem is I can't figure out where it plugs in. Doesn't appear to be the same as the 2016 and prior. Any idea where the connector is for the sensor? I know the sensors behind the dash but the connector should be out front somewhere.
Also, I ran water over the condenser and that didn't change anything so I don't think it is the fan clutch. Has been working perfectly now for the fourth day in 110+ heat. can'treally test anything until can get it to malfunction again. It must think it is at the dealer LOL
Also, I ran water over the condenser and that didn't change anything so I don't think it is the fan clutch. Has been working perfectly now for the fourth day in 110+ heat. can'treally test anything until can get it to malfunction again. It must think it is at the dealer LOL
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