Red Dot AC - Troubleshooting

[Bigfan]

this ac is wearing me out, none of speeds are working now. Sometimes when I turn it on low and middle work but never High, I have replaced switch, replaced resistor, replaced blower motor, basically have replaced everything inside it, with exception of two relays which i am having trouble locating replacements. Looks like I can buy a new old stock unit online delivered for $200 bucks, think its worth it at this point? Also assuming the 60 amp alternator puts off enough amperage for the ac? If not where can I pick up new larger alternator?

Should be in the blower box. It will be somewhere between the switch and the blower unit. On my MCC unit it is screwed to the blower unit.

You need to do proper diagnostics before going that far though. Take your test light and check to see if you have power to the blower motor on high, if yes, replace blower motor, if no remove the main fan switch and check for power out of the switch on the high, if no power but there is power to the switch replace the switch, if yes then check continuity of the wire from switch to blower motor. if it's good locate the resistor and check for power to it and coming out of it on high. If the continuity is bad then you more than likely have a resistor in line as it is open and dropping power .

 

[Lindsaym151]

My red dot compressor is squealing at 50 mph. what will cause this? I have a new system, with correct amount of freon and tight v groove belt. Tanks for any help!

 

[Coug]

My red dot compressor is squealing at 50 mph. what will cause this? I have a new system, with correct amount of freon and tight v groove belt. Tanks for any help!

I'm guessing you say it's the compressor because you only hear the squeal when the aircon is engaged at those speeds, but how do you know it's actually the compressor and not something else in the belts system making noise due to the increased belt load?

Belt squeal or bearing squeal or some other type of squeal?

Vehicle speed shouldn't be a factor in the aircon operation, other than the additional stress placed on the engine or the higher engine RPMs.

Is it constant squeal above those speeds every time you are going that fast, or does it come and go?

Can you recreate the squeal by holding the throttle pedal down when not moving, or is it only when driving?

Does it happen under heavy acceleration also?

How much is "the correct amount of freon" as there has been some debate about this?

 

[Mullaney]

My red dot compressor is squealing at 50 mph. what will cause this? I have a new system, with correct amount of freon and tight v groove belt. Tanks for any help!

.
You might rub a little bar soap (like you would wash your hands with) on the belts - ONE AT THE TIME - and if the squeak goes away you found a tired or loose belt.

Have to say it: DON"T LOSE A FINGER because those belts will rip off a finger so quick you won't have time to blink!

.

 

[Milcommoguy]

Blink and see the sign, CAMO