the summer is coming up and i wanna let my windows up and blow my a/c... the ss is 31 years old and who knows when the last time its been serviced for the a/c unit. im switching to r134 a my questions are whats the best way to overhaul my unit ( hoses, compressor, etc...) before i take it in to get refrigerant. and has any one done there a/c unit on here. i searched the forums and its really nothing from start to finish so i said i would make a topic. so hvac guys put your expert brains on this thread.
a/c hvac... cold air please....
- Thread starter two90west
- Start date
- Status
Is there any Freon 12 left in the system? If not, then assume that it has been open to atmosphere for some time. You probably have a leak somewhere, and you will want to track that down before you spend gobs of money. Try turning the compressor by hand( not the pulley, but the center section of the clutch ( looks like a triangle on the front of the compressor- I use a large channel lock to grab and turn it. Don't use the center bolt in the middle of the pulley- you can change your air gap adjustment if you turn with that bolt). If the compressor turns, you may be OK. However, the seals need lubrication from the freon/oil mixture, and if your's has not been run in a while, the seals are probably gone ( usual place for the leak to start). Seals can be replaced, but IMHO, it's cheaper/easier to just get a new/reman compressor. Be aware that the R4 style compressor has a harder time running R134a, and in my experience only last a year or so under the higher pressures (YMMV).
You will need to replace the accumulator and orifice, flush the lines, evaporator and condenser with AC Flush. Replace all the o-rings with Green O-rings. Lubricate them with Ester Oil before assembling. Use Ester Oil as a replacement oil in the system. 4 OZ in the accumulator, 4 Oz in the compressor ( Drain any oil in the compressor, new or used. Do not flush the compressor). I use the oil with the Leak Dye included- makes it easier to track issues later. Seal everything up, and pull a vacuum for 30 minutes, and then see if it holds for at least 1 hr. If it holds, pull an additional 30 minutes to 1 hr of vacuum, and then charge with 4 12 oz cans of R134a. Before you charge, rotate the compressor by hand to distribute some of the oil from inside it, so you don't have hydro-lock when it kicks on. If you have a leak, time to start tracking. You can apply air pressure ( nitrogen preferred, but who has that?). If not readily apparent, try a soapy solution on all fitting, and even over the condenser if you suspect a leak there. I use the bubble solution kids use to blow bubbles.
If you suspect that your compressor failed at some time, then I suggest replacing the condenser as well as the compressor. It's hard to flush out particles from the condenser, and you will likely just mess up your new compressor over time. Another reason is that newer R134a works best with a Parallel Flow ( sometimes called 6mm) condenser,so if you do replace, find one of those and your cooling performance will be improved.
This should get you started. There are some finer details on charging, but many posts on the net about that.
You will need to replace the accumulator and orifice, flush the lines, evaporator and condenser with AC Flush. Replace all the o-rings with Green O-rings. Lubricate them with Ester Oil before assembling. Use Ester Oil as a replacement oil in the system. 4 OZ in the accumulator, 4 Oz in the compressor ( Drain any oil in the compressor, new or used. Do not flush the compressor). I use the oil with the Leak Dye included- makes it easier to track issues later. Seal everything up, and pull a vacuum for 30 minutes, and then see if it holds for at least 1 hr. If it holds, pull an additional 30 minutes to 1 hr of vacuum, and then charge with 4 12 oz cans of R134a. Before you charge, rotate the compressor by hand to distribute some of the oil from inside it, so you don't have hydro-lock when it kicks on. If you have a leak, time to start tracking. You can apply air pressure ( nitrogen preferred, but who has that?). If not readily apparent, try a soapy solution on all fitting, and even over the condenser if you suspect a leak there. I use the bubble solution kids use to blow bubbles.
If you suspect that your compressor failed at some time, then I suggest replacing the condenser as well as the compressor. It's hard to flush out particles from the condenser, and you will likely just mess up your new compressor over time. Another reason is that newer R134a works best with a Parallel Flow ( sometimes called 6mm) condenser,so if you do replace, find one of those and your cooling performance will be improved.
This should get you started. There are some finer details on charging, but many posts on the net about that.
- Status
Similar threads
