carrier aircon units

[jacko 63]

Can anyone help. We have a problem at work with 2 carrier split aircon units. They both run on hot or cold setting for approx 2 mins, then they shut down. We have had 3 different engineers out, and 2 said that it was the PCB, which was changed but did not rectify the problem. The other 1 said it was the thermo switch, which also was changed and also did not rectify the problem. Both units were well serviced, filters cleaned, gas checked etc...

Any thought guys.

[AbsoluteWDJ]

Can anyone help. We have a problem at work with 2 carrier split aircon units. They both run on hot or cold setting for approx 2 mins, then they shut down. We have had 3 different engineers out, and 2 said that it was the PCB, which was changed but did not rectify the problem. The other 1 said it was the thermo switch, which also was changed and also did not rectify the problem. Both units were well serviced, filters cleaned, gas checked etc...

Any thought guys.

You will need more info than this my friend. Refrigerant type, pressure and temperatures would help. Two simple questions: 1. Have they worked in the past ok? 2. If so..when did you notice the fault?
Strange the two of them are under fault at the same time with the same problem. Is your set temps higher than your room temps in heating and vice versa in cooling?

[jacko 63]

they have worked fine till now.R22 is the gas and no the set temp is not higher than the room temp.These units are on seperate villas they both went down with this problem within 3 weeks of each other.

thanks

jacko 63

[jacko 63]

they have worked fine till now.R22 is the gas and no the set temp is not higher than the room temp.These units are on seperate villas they both went down with this problem within 3 weeks of each other.

thanks

jacko 63

[al]

if units are shutting down so quickly it should be fairly handy to see why.

Are you losing the compressor run command from the indoor?

If not then the fault is on the outdoor, hp/lp switch or thermal overload, indoors are a different matter though.

I think these old 22 units had a thermistor wired from the indoor to the outdoor, is this ok and is the inter connect ok and polarity correct??

What kind of suction/discharge temps/pressures you getting, more info pleeeeeeease.

al

[AbsoluteWDJ]

When you say they shut down after 2 mins.....are they tripping the main fuse or do you receive a fault perhaps on the indoor unit. It could be a sequence of LED's flashing. I'm not familiar with carrier split systems fault code process but most split systems will have some sort of fault indication. Do the outdoor fans and compressors run?