Contactor relay not pulling in.

Briank213

I am attempting to fix this myself with all the proper precautions.

- First, the contactor stopped pulling in. I ordered a new one and replaced it. New one is not pulling in either. I bought a multimeter and I am showing 24V coming out of the transformer and into the unit outside. The positive (Blue wires) then goes into a red piece connected to the coils. Not really sure what it is but there is no voltage on the lead at the relay after this point...

Picture attached. Not sure what it is.

biggles

pressure control safty(Hi or Lo?) the 24Vs for the contactor coil are in series with this....does it have a red push buttom on top might be tripped...read each of those blue wires seperatly...24V but none out it is open

Doc Holliday

In English, Biggles is saying that that is either a high or a low pressure switch and it's tripped/open. I can't tell from your pic but if it's a low pressure switch then your system is running low on refrigerant. If it's connected to the high side pressure line than you've got other issues, possibly a restriction in the refrigerant lines.

The switch is doing it's job of protecting the compressor. In other words you have a refrigerant problem, not a low control voltage problem.

I got your back, Biggles.

__________________
Thanks.

Marty S.

Yep. It's on the condensing coil so it's a high pressure switch. Bad fan motor,fan motor capacitor or dirty coils cause it to trip and protect the compressor. Push the red rubber button on the end then figure out which of the above caused the problem.

beenthere

looks like a manual reset high pressure switch. Push the reset button in. If the condense fan doesn't run, then you know why it tripped. Also, wash your condenser coil before resetting the switch.

Briank213

Thanks for all the replies. Least its something easy I hope.

I am replacing this unit after the summer if it makes it the duration. Its older than old but its been working so im trying to run it till the wheels fall off. Sadly its got a freon leak somewhere that drains the freon each year and i have to get it filled with a grade of freon they are going to stop producing. The price on the old freon has doubled as a result.

I will hose down the coils.. but the switch may have tripped when it ran low and i had it refilled.

biggles

with that rate of leaking so goes the droplets of oil for the compressor that travel around during a cycle.might do a look see feel of all the refer lines to see if you pick up oil soaked armaflex or wet spots.that change out happening latter in the year the lines will need to be verified that a leak isn't there with the new stuff

beenthere

Being low on charge won't make a high pressure switch trip.