I just purchased a 1989 GMC Sierra 1500. I'm wanting to try and fix the AC myself to learn and also because the closest AC shop is over an hour from here. It is currently an r12 system, but with the price of r12 I'm thinking I should go ahead and convert to r134a.
So far I've bought manifold gauges and a vacuum. When I first got the truck, I pushed one of the valves and heard pressure in it. I just did it for a second because I know you're not supposed to. I tried to connect the gauges, but when I got them in the mail, I realized I'm missing an adapter for the high side of the gauges. I then pushed one of the valves in again and heard no pressure coming out of it. So it must not have had much left in it.
I did jump the low pressure switch for a few seconds and the compressor engages and has no noises, so I'm hoping it is good.
I'm going to pick up a retrofit kit so I can connect my gauges. Should I see if it holds a vacuum at that point (probably not because it's now empty and it had to go somewhere)? Or should I go ahead and flush the system, change the o-rings, accumulator and orifice tube, see if it holds a vacuum, then refill with refrigerant and ester oil? If so, is that all I need to change to convert to r134a? Doing research, some say I need to change condenser, get new high and lower pressure switches and get barrier type hoses, but others are saying I don't need to do that?
Any help would be greatly appreciated.
So far I've bought manifold gauges and a vacuum. When I first got the truck, I pushed one of the valves and heard pressure in it. I just did it for a second because I know you're not supposed to. I tried to connect the gauges, but when I got them in the mail, I realized I'm missing an adapter for the high side of the gauges. I then pushed one of the valves in again and heard no pressure coming out of it. So it must not have had much left in it.
I did jump the low pressure switch for a few seconds and the compressor engages and has no noises, so I'm hoping it is good.
I'm going to pick up a retrofit kit so I can connect my gauges. Should I see if it holds a vacuum at that point (probably not because it's now empty and it had to go somewhere)? Or should I go ahead and flush the system, change the o-rings, accumulator and orifice tube, see if it holds a vacuum, then refill with refrigerant and ester oil? If so, is that all I need to change to convert to r134a? Doing research, some say I need to change condenser, get new high and lower pressure switches and get barrier type hoses, but others are saying I don't need to do that?
Any help would be greatly appreciated.
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