AboutHoward Livingston Expertise Can answer questions on electrical control circuits, power supply,airflow & distribution, electrical components,refrigerant problems,gas, electric & propane furnaces.No boiler or refrigerator or oil fired furnaces experience.Just HVAC questions please.
Experience 35 years experience in residential & light commercial repair & installation.
Question okay let me start by saying i am a residential/commercial service tech. my question is one, more for reassurance or to insure that i am not missing anything. ok the condenser wasn't coming on when switched to cool. inside blower was running, and my 220 was present at contactor. so i assumed transformer, which i replaced after i put a volt meter to it and assured myself. still nothing so go to contactor, 220 present only one side of contactor getting 24v, checked high and low cut outs, they are fine. so i followed the wiring back, now this is where my question will be asked. on the circuit board terminal strip y is sending 24, but c isn't. the terminal strip is not replaceable, so does that mean that the circuit board is faulty and needs replacement? or am i jumping the gun. i appreciate any and all help that u can offer. also if u need any additional info just ask
Answer Are you getting 24 v between Y & C on the board WITH THE RED & WHITE wires to the outside unit disconnected ?? That ought to prove the trouble is in the red & white wire OR inside the unit. You said there are hi * lo cutouts in the unit ?? If one is tripped your not getting 24v to close the contactor. Right ? So if you manually press in the contactor & it runs, its the control circuit thats open. So it can be either the red or white wire briken & oopen, or a pressure switch has tripped. Disconnect the Y wire & ohm the wires going thru the 2 pressure switches to find the trouble. More difficult to write than to do. Good luck
