No cold a/c
- Thread starter FJK1954
- Start date
westmicher
Veteran Expediter
Yeah, your cabin filter could be LOADED with junk. Mine was.
Cabin filters would be my first check as well. If that is ok then either high pressure switch or heater control valve. Easy to test each. On the HPS, see if cold lines are actually cold going in to the firewall. If cold, then check the HCV and if it is hot on both sides, that needs closed (cable operated or electronic) or replace.
If not sure on the filters, take them out and run it for a few minutes and see if it blows cold. That will answer that question.
If not sure on the filters, take them out and run it for a few minutes and see if it blows cold. That will answer that question.
First thing first A/C work can be hazardous so you do this at your own risk. If you destroy somthing, or if you or anyone gets hurt or killed its your fault.
Now with that said lets move foward....
You need a couple basic tools.
1) An A/C pressure guage set with a charging line abbout 50 bucks at Carquest.
2) A dial thermometer.
3) Plain refridgerant or if you have alot of miles ONE can of high milage this contains a sealant. and one can regular Older systems can develop microscopic pores not major enough to warrent replacement, its just wear and tear.
4) LEATHER INSULATED WORKGLOVES AND SAFETY GOGGLES. Freon will freeze any flesh it comes into contact with.
If you need more then 1 to 1-1/2 cans for cars 2 most light and medium duty trucks if you need more have an AC shop get into it.
Check what kind is required for your vehical most run 134 A but a newer formula is out there I dont recall the name but, Its a whole different animal if you run 134a through it you will destroy your A/C system.
If youre a newbee A/C works like a heat pump by recovering the available cold from the outside air. Yes even when ist 100+ degf there is cold as freon boils at -15.43deg F. or 26.3 deg.C newer formulas even colder. It picks up the heat from inside the vehical and releases it into the atmosphere. This is all dependant on having correct line preasures.
STEP 1 Find out wich line is the high side and wich is the low side. carefuly touch the metal lines of both the high and low sides the high side should be hot. (compressing a gas increases the temp.) and the low side cold.
Get an accurate outside temp reading and put the thermometer in the dash vent.
if you can get betwene 30 to 40 deg difference its good to go.
. Contact an A/C shop and find out what youre cut in and cut out preasures are supposed to be. (when the compressor kicks on and off) Get the required readings at idle and 2000 RPM.
Now here is where you use the preasure guages using gloves and goggles attach your guage set run the AC on high, open all the windows and doors and write down the readings have somone hold the throtle at abbout 2000 rpm and write them down.
If both readings are low usualy freon is low try adding freon and see if this helps FOLLOW THE SERVICE MANUALS DIRECTIONS TO THE LETTER.
Add freon slowly if the thermometer and preasure guages dont improve during your first can stop and take it to a shop.Only use one can with sealant as too much will ruin your system add this can first.
After charging even if you get cold air check your preasures in a few hours and then every couple days for a week or so and see if they drop if they do you have a leak take this to a shop as most state have a heafty fine for cracking open an AC system.
If you have any doubts take it to a shop that specializes in A/C work.
Good luck
Bob Wolf
Now with that said lets move foward....
You need a couple basic tools.
1) An A/C pressure guage set with a charging line abbout 50 bucks at Carquest.
2) A dial thermometer.
3) Plain refridgerant or if you have alot of miles ONE can of high milage this contains a sealant. and one can regular Older systems can develop microscopic pores not major enough to warrent replacement, its just wear and tear.
4) LEATHER INSULATED WORKGLOVES AND SAFETY GOGGLES. Freon will freeze any flesh it comes into contact with.
If you need more then 1 to 1-1/2 cans for cars 2 most light and medium duty trucks if you need more have an AC shop get into it.
Check what kind is required for your vehical most run 134 A but a newer formula is out there I dont recall the name but, Its a whole different animal if you run 134a through it you will destroy your A/C system.
If youre a newbee A/C works like a heat pump by recovering the available cold from the outside air. Yes even when ist 100+ degf there is cold as freon boils at -15.43deg F. or 26.3 deg.C newer formulas even colder. It picks up the heat from inside the vehical and releases it into the atmosphere. This is all dependant on having correct line preasures.
STEP 1 Find out wich line is the high side and wich is the low side. carefuly touch the metal lines of both the high and low sides the high side should be hot. (compressing a gas increases the temp.) and the low side cold.
Get an accurate outside temp reading and put the thermometer in the dash vent.
if you can get betwene 30 to 40 deg difference its good to go.
. Contact an A/C shop and find out what youre cut in and cut out preasures are supposed to be. (when the compressor kicks on and off) Get the required readings at idle and 2000 RPM.
Now here is where you use the preasure guages using gloves and goggles attach your guage set run the AC on high, open all the windows and doors and write down the readings have somone hold the throtle at abbout 2000 rpm and write them down.
If both readings are low usualy freon is low try adding freon and see if this helps FOLLOW THE SERVICE MANUALS DIRECTIONS TO THE LETTER.
Add freon slowly if the thermometer and preasure guages dont improve during your first can stop and take it to a shop.Only use one can with sealant as too much will ruin your system add this can first.
After charging even if you get cold air check your preasures in a few hours and then every couple days for a week or so and see if they drop if they do you have a leak take this to a shop as most state have a heafty fine for cracking open an AC system.
If you have any doubts take it to a shop that specializes in A/C work.
Good luck
Bob Wolf