Hi, I'm a newb to this list, but I have HVAC experience. I have what seems odd behavior of a 2011 Honda CRV upon changeout of the compressor.
- As far as I can tell the problem with the old compressor was the clutch (I didn't disassemble to look inside, but the clutch wouldn't engage and the comp seemed to pump when turned by hand)
- I changed the compressor, expansion valve and drier insert, added 4 oz oil (provided with kit)
- Pumped down system
- I have gauge set, and used autoparts store cans of r134
- data plate says 17.4 Oz capacity
- figured two cans would be more than enough (12 oz by weight), and I could bleed some off or stop short on second can if the pressures got a little high
- filling system saw normal behavior, but noticed the low pressure switch never operated, which is normal when you first start to fill. Low side pressure at/below 20 psi didn't open it.
- after putting both cans in, during idle, system pressure looks fine, maybe even a bit low, but at 1500-2000 low side drops below 20 psi
- got a little flash of frost on suction line
- all indications were that it needed more refrigerant ???
- with great trepidation, I got another can and started adding, finally saw a little more normal pressures, but nothing indicating overcharging (high side hardly went over 200 psi (temp outside was 75-80 F)
- after dumping all three cans in, at high idle (2000 rpm) the thing started rapidly cycling even though the low side pressure was around 30 psi (figured high pressure switch was cycling - I didn't have the high side gauge on at the time)
- I got scared and started bleeding gas off
- now I'm back to what looks like low pressures but the system seems to operate normally 20 psi at 1500 rpm, about 200 high side
What is going on? Is the low pressure switch bad? Is it still overcharged? Is it undercharged?