Did a thorough coil cleaning of a couple of old
20 hp singer mid temp refer units today.
Before I cleaned the condenser coils the pressures
were 29 low side, and 197 high. These units do
use TXV valves, and they were cooling great.
After giving them a good cleaning, and coils had time
to dry out, and warm back up the pressures have
dropped to 10 low side, and 160 high. Using R409a.
They are still cooling good, but that seems mighty
low, worried they will freeze up over time.
I should not have to adjust the TXV valves, after
cleaning, so what is up?