Both AC Units won't keep running.

[rschley]

I have 2 AC units that run intermittently. We are in the deep south with 80 degrees on the way and have 2 AC units that decide when they want to work. Can run well together for hours then they switch to fan only mode. When switched on the fans run showing 6 amps draw on Kenwood and about 14 amps when both are cooling with the compressor engaged. Thermostats are set low to 60 degrees, which we never reach.

Have to add that I posted earlier that my Leg 2 is off showing that I have limited electrical input, but both units and the dryer have pulled 24 amps and run well in unison on Leg 1. 

Is there power sharing going on that I need to live with or is there a fix to allow either one or the other or both units to be reset to engage the compressors? 

Any input would be great. Hanging out in the South until the snow melts in Northern Minnesota so I can get into my yard. 

Thanks in advance. Your input is always awesome stuff.

 

 

[96 EVO]

Both compressors aren't running if your only drawing 14A!

That's about what one unit draws.

Your on 50A shore power?

Edited April 1, 2023 by 96 EVO

[Trinidaddave]

You first need to determine what is shutting them down.

1. Are the receiving proper voltage?  You will need a meter for that.

2. Are the compressors drawing too much current?  Resulting in internal overload opening.  This will require an ammeter.

3. Are the compressors overheating?  Maybe the units require service and cleaning.

4. It’s not normal for both units to be wired to line #1.

5. don’t rule out the thermostat just because it’s set at 60.  It could be a component in the thermostat overheating.

it’s really hard to guess without doing some checks.

 

[rschley]

41 minutes ago, 96 EVO said:

Both compressors aren't running if your only drawing 14A!

That's about what one unit draws.

Your on 50A shore power?

Ok. 14 amp for just 1 makes sense. I misspoke. You are right.  We are on 50 amp shore power. 

10 minutes ago, Trinidaddave said:

You first need to determine what is shutting them down.

1. Are the receiving proper voltage?  You will need a meter for that.

2. Are the compressors drawing too much current?  Resulting in internal overload opening.  This will require an ammeter.

3. Are the compressors overheating?  Maybe the units require service and cleaning.

4. It’s not normal for both units to be wired to line #1.

5. don’t rule out the thermostat just because it’s set at 60.  It could be a component in the thermostat overheating.

it’s really hard to guess without doing some checks.

 

Thanks for your input. All makes sense.  I have meters and will do some checking. Bought unit recently and I know one unit is old and the other is 2018 install. 
I will do some checking and servicing.  
Thanks!!  

[Tom Cherry]

Couple of things….exactly how did you define that you have “limited power input” on leg 2?  If you mean the voltage is lower and you are in a CG with a bunch of 5W and TT, THEN…. they are pulling down the L2 voltage as the idiot electrician did not keep switching and put too many 30’s on that leg

OK, you have a 10Kw Genny.  Fire it up and disconnect the shore.  Do you still have the same problem?  If so, it’s in your AC’S.  

Read your manual or figure out how to pull the HVAC filters.  Wash them.  Rinse them. Roll them up in a towel and wring out the water.  They need to be dry, but a little damp wont hurt. Did that improve it?  Even if the Genny fixed it, then check the filters.

Finally, and I doubt it is the issue…do a reset on the five button thermostat(s).  Use the bottom switch.  Turn off power.  Hold in Mode & Zone buttons.  Than power on.  FF will be displayed.  That resets any “glitches”.

IF it still exists, you have an issue.  

NOW, ONE LAST DITCH.  IF YOU ARE COMFORTABLE….Unplug Shore.  Turn off or trip the circuit breaker on the Genny.  Pull the cover off the main 50 A panel and tighten every screw or fastener inside.  This should be done as preventative maintenance every 3 - 5 years.  Look at all the breakers.  They snap in from one side. If they are not perfectly aligned or one sits further up or down, PUSH HARD ON THE BREAKER….use a thumb on each end and push and seat.

Thats it