Long story short, I got a call: A small walk-in cooler no cooling. Trouble shoot it. the compressor didn't start. the start and run winding are 11 ohms,3 ohms and r to s total 14 ohms. it pull 32 amps which match the LRA on the nameplate then circuit opened by the Klixon overload. Checked capacitor,it's 140uf, (its range should be 145uf to 175 uf.)
It's single phase,1/3 hp,capacitor start,induction run tecumseh compressor. It's nameplate marked with R134a,but someone made a note " R414" on it (don't know R414a or R414b hot shot). The comp was changed half year ago by somebody else. the walk in is more than 20 years and it might be a R-12 system before(info offered by the owner)
My questions are
1.anyone has any good method to check the current relay at this kind of situation?
2.if the guy didn't flush the system, coverted the R12 to hot shot with a R134a comp.will it be damage?( if the old r12 comp didn't burnt out before)