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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3382
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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01 Chevy cab over Isuzu diesel 4800 ac some times does not

Customer Question

01 Chevy cab over Isuzu diesel 4800 ac some times does not blow cold enough new system with oem parts including condensor 100 degrees out fan on low and recirculate temp 46 degrees pressure 290 low 35 to 40 at idle bring it up to 1800 rpm high side 300 low 29 put fan on high at idle 62 degrees high side 325 low side 50
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Wayne replied 1 year ago.

Hi I'm Wayne

I will help you with this

does it do it when truck is hot only

Customer: replied 1 year ago.
It's always normal in the morning
Expert:  Wayne replied 1 year ago.


Thank you for that

I noticed that pressure is high on the high side

I suggest to wash radiator good with dish soap and a hose

Customer: replied 1 year ago.
Radiator is new also new condensor is by itself with its own fan if ur not an expert on this vehicle please opt out
Expert:  Jeremy replied 1 year ago.

My name is ***** ***** I will assist you with your question today.

I'm an independent contractor and I don't get paid until a rating has been made.

We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence!

Is the condensor fan spinning good?

Was the system pulled down, vacuumed for at least 1 hour, and then recharged after the fresh parts were put on?


You want a 5 star service and I want to provide a 5 star service. Please consider that I don't know your skill level as well as I can't see, touch, smell, hear the vehicle/machine in question. Please provide as much detail as possible and I will provide as much back.

Once an answer is provided, you should see a rating screen. Please rate my personal service to you. The ratings are my personal feedback,

they are not the site feedback.

Thank you for allowing me to assist you through Just Answer!


Expert:  Jeremy replied 1 year ago.

I know where the condenser fan placement is, it gets a lot of heat from the asphalt wit hhow it pulls the air up. I am in Florida and it pulls the air straight from the ground. We have to check these in the shop to get an idea of what they will do.

The fans are not that great either. They are always going

Unplug the fan and at the connector, make sure you are getting a full 12 volts to the fan and not lower. That can cause the fan to spin slower and bringing the head pressure up. Your suction looks good, but the head pressure is getting high like the condenser isn't getting enough air across it.

Customer: replied 1 year ago.
Ok I will check that tomorrow and get back to u
Expert:  Jeremy replied 1 year ago.

sounds good.

Customer: replied 1 year ago.
sorry the truck is gone out of town for couple of days I probably won't get to check it until Monday of next week I will be in touch as soon as I do
Expert:  Jeremy replied 1 year ago.

I won't be back until Thursday, but I will tr and check in on Monday afternoon and again Tuesday.

I have the email replies turned on.

Good day!