HVAC Help

[GCSI]

I’m having an issue with CruiseAir split system, symptoms are (SMX Controls)
- Thermostat Cooling light illuminated
- Thermostat Cool light illuminated
- Fan automatically cycles to high
- Blower is operating
- No codes on SMX
- While in bilge next to compressor unit, I hear relays but unit does not engage (compressor does not engage)
- Compressor is hot too touch
Any ideas for a quick fix or should I start begging for a service call??

Tampa Bay Area

Brett

 

[Pascal]

Compressors have thermal safeties. They will self reset once temp drops down to safe level. Could be a defective compressor. Usually a water flow problem will trigger high pressure before the compressor get hot but maybe it will under certain conditions.

Does it restart after it cools, how long does it ru ?

 

[zigzag930]

When cold starting the system, does the compressor run at all?

If it does and shut's off within a minute or so, then you may have a water flow issue or the charge in the system is off. Either will cause the compressor to run hot and shut down on thermal overload.

If the compressor does not run, it could be a start capacitor. Easy and inexpensive to try that before calling for service. Just in case you are not familiar with capacitors, be very careful handling them. Turn off all power to the system and discharge them by grounding them out with a screwdriver or other "INSULATED HANDLE" device. If not discharged and you touch the terminals, you may get a free ride across the engine room.

 

[JD5652]

I’m having an issue with CruiseAir split system, symptoms are (SMX Controls)
- Thermostat Cooling light illuminated
- Thermostat Cool light illuminated
- Fan automatically cycles to high
- Blower is operating
- No codes on SMX
- While in bilge next to compressor unit, I hear relays but unit does not engage (compressor does not engage)
- Compressor is hot too touch
Any ideas for a quick fix or should I start begging for a service call??

Tampa Bay Area

Brett

I would call for a service tech... sounds like compressor is not energizing for some reason. The two most common error messages on the keypad is "HI PS" or "LO PS"... HI PS is not enough water flow.... LO PS is usually low freon.... if the compressor is HOT to the touch... sounds like you might have a seized compressor.... but that's beyond my keyboard troubleshooting abilities...

 

[JD5652]

When cold starting the system, does the compressor run at all?

If it does and shut's off within a minute or so, then you may have a water flow issue or the charge in the system is off. Either will cause the compressor to run hot and shut down on thermal overload.

If the compressor does not run, it could be a start capacitor. Easy and inexpensive to try that before calling for service. Just in case you are not familiar with capacitors, be very careful handling them. Turn off all power to the system and discharge them by grounding them out with a screwdriver or other "INSULATED HANDLE" device. If not discharged and you touch the terminals, you may get a free ride across the engine room.

AH ha!.... good catch!... usually there are two capacitors... a start capacitor and a run capacitor... super cheap to buy and try... can get them from Grainger if you get the label info off each and order them... usually less than $20 each....

 

[GCSI]

After the compressor cooled for 8 hrs, still no joy, just a “buzz” for about five seconds then nothing. Earliest competent help will be next week. Plan on installing two new capacitors tomorrow as a hail
Marry, will report back.

 

[Pascal]

Well
If it a not the capacitors then the compressor maybe defective. Usually a locked compressor trips the breaker though. Odd

 

[scottinsydney]

There is also a small relay used for start/run in the box.

You can swap this relay over with a known good one.

There are also ohms tests you can do to check compressors wirings. Youtube will show you how.

 

[tjshuler]

Well
If it a not the capacitors then the compressor maybe defective. Usually a locked compressor trips the breaker though. Odd

Could one of the windings be open?

 

[rwaldrop13]

The buzzing noise really sounds like the start/run capacitors. We had same issue with house AC unit and I was able to replace capacitor with same one for under $50. Grainger should have it, but check and see if you have a CC Dixon in the area also. They tend to be cheaper than Grainger.