3 A/C Units - Front and Back Units

rlw1210 · 09-08-2020, 07:52 PM

I have a 2016 Pinnacle FLSA with 3 factory installed AC Units (I live in Texas so it's hot and a must!). Per design, the front and back units can not run at the same time and alternate. Recently the front unit won't come on unless I "trick" it. The trick is...turn the back unit on and set it down 1 degree, it will come on, cool the 1 degree and when it cycles off, the front one will usually cycle on. It's like the front unit won't come on because it thinks the back unit is running. Anyone else have this issue? Any suggestions?

All three units cool well (although after reading these forums I'm going to follow the youtube video about the barrier) so it's not a cooling problem - it's just getting the front unit to think it's ok to cycle on. This just recently started. I got up on the roof and took the cover off all three units, cleaned them up really good and no wiring, loose wires or cracked insulation/wire issues.

Thank you in advance.

**JFlightRisk** · 09-08-2020, 08:06 PM

It sounds like somewhere in that power system is a control module, designed to share the power available from one circuit breaker, between two heavy loads. It may be malfunctioning. I have no idea where it may be on your rig, but maybe someone else here knows.

Packerbacker_TX · 09-09-2020, 11:46 AM

Quote:

Originally Posted by rlw1210

I have a 2016 Pinnacle FLSA with 3 factory installed AC Units (I live in Texas so it's hot and a must!). Per design, the front and back units can not run at the same time and alternate. Recently the front unit won't come on unless I "trick" it. The trick is...turn the back unit on and set it down 1 degree, it will come on, cool the 1 degree and when it cycles off, the front one will usually cycle on. It's like the front unit won't come on because it thinks the back unit is running. Anyone else have this issue? Any suggestions?

All three units cool well (although after reading these forums I'm going to follow the youtube video about the barrier) so it's not a cooling problem - it's just getting the front unit to think it's ok to cycle on. This just recently started. I got up on the roof and took the cover off all three units, cleaned them up really good and no wiring, loose wires or cracked insulation/wire issues.

Thank you in advance.

3 AC units.. wow. Must be a monster of a rig to need 3. My suggestion would be to invest in a few Micro Air Soft Start modules. They're inline, easy to install and reduce the total startup wattage. I suspect this may allow you to run all 3 if it ever gets over 110'F LOL.

Good Luck

rlw1210 · 09-09-2020, 12:01 PM

Quote:

Originally Posted by Packerbacker_TX

3 AC units.. wow. Must be a monster of a rig to need 3. My suggestion would be to invest in a few Micro Air Soft Start modules. They're inline, easy to install and reduce the total startup wattage. I suspect this may allow you to run all 3 if it ever gets over 110'F LOL.

Good Luck

It is a monster....during the heat of the day both units run (given that by design only two units can run at a time) and the best it can do is keep it at 80-ish degrees inside. I'll look into the Micro Air Soft Start modules - thanks for the suggestion.

Bookemdanno · 09-09-2020, 12:03 PM

Quote:

Originally Posted by Packerbacker_TX

3 AC units.. wow. Must be a monster of a rig to need 3. My suggestion would be to invest in a few Micro Air Soft Start modules. They're inline, easy to install and reduce the total startup wattage. I suspect this may allow you to run all 3 if it ever gets over 110'F LOL.

Good Luck

He beat me to it! I have them on both my units and I can runs both a/c’s and the residential fridge on 30 amp. There not cheap, but worth it if you want all your a/c’s to run!

RedHorse1 · 09-09-2020, 07:11 PM

I would expect the gizmo that keeps the two from running at the same time would have to be removed if you install soft starts before they would work together.

Chris Wendt · 09-10-2020, 09:14 AM

Quote:

Originally Posted by rlw1210

I have a 2016 Pinnacle FLSA with 3 factory installed AC Units (I live in Texas so it's hot and a must!). Per design, the front and back units can not run at the same time and alternate. Recently the front unit won't come on unless I "trick" it. The trick is...turn the back unit on and set it down 1 degree, it will come on, cool the 1 degree and when it cycles off, the front one will usually cycle on. It's like the front unit won't come on because it thinks the back unit is running. Anyone else have this issue? Any suggestions?

All three units cool well (although after reading these forums I'm going to follow the youtube video about the barrier) so it's not a cooling problem - it's just getting the front unit to think it's ok to cycle on. This just recently started. I got up on the roof and took the cover off all three units, cleaned them up really good and no wiring, loose wires or cracked insulation/wire issues.

Thank you in advance.

I use to have this exact fifth wheel and there is a relay behind the electrical panel that cycles the front and rear unit. Mine went out and I had to replace it. The trick is you have to pull the whole electrical panel out. Luckily there is enough slack in all the wires that you are able to pull the panel forward and set it on the ground. You will see the box screwed to the floor with the relay in it. You will have one romex coming from the panel and two pieces of romex leaving the box and going to the each AC unit. Make sure you turn the power off.

rlw1210 · 09-11-2020, 04:29 PM

Quote:

Originally Posted by Chris Wendt

I use to have this exact fifth wheel and there is a relay behind the electrical panel that cycles the front and rear unit. Mine went out and I had to replace it. The trick is you have to pull the whole electrical panel out. Luckily there is enough slack in all the wires that you are able to pull the panel forward and set it on the ground. You will see the box screwed to the floor with the relay in it. You will have one romex coming from the panel and two pieces of romex leaving the box and going to the each AC unit. Make sure you turn the power off.

Thank you! You don't by chance remember the part number or anything for this relay do you? Or, where did you get your replacement relay?

rlw1210 · 09-11-2020, 04:47 PM

I just found a similar thread: https://www.jaycoowners.com/forums/f...lem-47999.html

Chris Wendt · 09-11-2020, 04:56 PM

Quote:

Originally Posted by rlw1210

Thank you! You don't by chance remember the part number or anything for this relay do you? Or, where did you get your replacement relay?

Precision circuits
630-515-9100
Called a powered shared switch
J.charest@precisioncircuitsinc.com
Hope this helps

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