copeland compressor

[tcdmtcdt]

I recently installed a copeland compresso 5ton, replaced capacitor got gas in the system but the compressor won't start. The condenser fan starts up but nothing? Any suggestions, contactor is brand new and it doesn't have a low pressure switch reset

[james10]

Have you tried hp switch? are you getting voltage to your contactor coil? are the compressor fuses/overloads ok? is the unit setpoint low enough for the unit to run? what type of kit is the compressor on

[tcdmtcdt]

I thought about the hp switch but couldn't find one on the condenser unit. I am getting line voltage, then I turned the thermostat to cool my contactor pulls in. I am getting power through the contactor for a few seconds then it goes away. I put my ammeter to see if I was getting enough amps and noticed it was 2 or 3 amps below what is stamped on the compressor. There are no control relays on the condensing unit
just a capacitor and a contactor. That's why I'm confussed because there is really not too much to look for. Any suggestions would be appreciated

[james10]

Does the power stay on at the line in of the contactor if it does and you lose voltage on the load side with the coil pulled in i'd replace the contactor i know you said it was new but these things happen

[james10]

PS is the compressor capacitance start or capacitance run? is ther any compressor protection modules robert shaws etc

[dane mccarthy]

are you getting voltage through the contactor and to the compressor? i would check voltage through contactor then at compressor, check capacitor again and check wiring is correct, is the compressor hot, could be an internal thermal overload either faulty or if it is hot it could be tripped!!

[powell]

My bets on a faulty contactor.

[botrous]

If the compressor is a single phase one it would do such proplems if the power cables are poorly selected or if the voltage is under the compressor rated voltage put a powerpack (supco or equivalent) to give the compressor a hard start.
I beleive that in your case the compressor pull of current while starting is decreasing the line voltage , those making the contactors relay deactivated.

[chemi-cool]

Hello Botrous, nice to see you again here.


tcdmtcdt,
5 ton compressor single phase??
Will you please give us the model?

Maybe that the capacitor belongs to the fan motor?

If the compressor and fan are on the same circuit and the compressor is trying to start, the fan will hardly turn as the tension will drop.

[Eric the King]

what model of copeland compressor do you have? as Botrous said a start pack may be required. all copelands single phase should be fitted with a start pack,if the comp. is a recip. you definitely need a start pack. Have you line voltage at the compressor terminals. Possibility that copeland wiring ex factory a problem I have seen it happen on two occasions.