Dometic heat pump & a/c vents

[Tall Guy]

Two questions about the a/c system on our 2017 Sunseeker 2400W:
1. In high temperatures (100+ in Utah this month), the Dometic heat pump will sometimes cycle on and off several times within 30 seconds to a minute. Both the compressor and fan cycle. This seems to happen as the inside temperature gets close to the thermostat setting. Is this common?
2. We noticed that the two a/c vents in the middle of the cabin, just in front of the a/c unit, have small wooden blocks (app. 2x2x1) we can see in the ductwork behind the vent openings. Neither is anchored or attached to anything; they are just sitting in the duct. My thinking is they were probably used as a jig or alignment aid during assembly, but I'm not sure. So, any thoughts on what they are or how to remove them? I'm not sure if the vent covers are supposed to snap out in some way.

Thanks,
Mike

[DaveJordan]

Originally Posted by Tall Guy

1. In high temperatures (100+ in Utah this month), the Dometic heat pump will sometimes cycle on and off several times within 30 seconds to a minute. Both the compressor and fan cycle. This seems to happen as the inside temperature gets close to the thermostat setting. Is this common

I think this was discussed in a recent thread. If you've got the fan set on "Auto" (at the thermostat) then the whole thing more or less goes off for a few seconds, then goes back on, when the fan switches speeds. You might try setting the fan to a single speed to see if the behavior goes away.

Originally Posted by Tall Guy

2. We noticed that the two a/c vents in the middle of the cabin, just in front of the a/c unit, have small wooden blocks (app. 2x2x1) we can see in the ductwork behind the vent openings. Neither is anchored or attached to anything; they are just sitting in the duct. My thinking is they were probably used as a jig or alignment aid during assembly, but I'm not sure. So, any thoughts on what they are or how to remove them? I'm not sure if the vent covers are supposed to snap out in some way.

I'm not exactly sure which vent cover you're talking about, but if it's like mine, it's the main cover in the center of the ceiling and has vents for both air from the A/C and air returning to the A/C. The return air cover (toward the front of the RV) is removable to allow cleaning of the dust filter. The A/C outlet vents (which can slide either open or closed) are builtin to the main cover. I would take the return air cover off and look around inside to see if there's an obvious way to remove the whole cover.

As far as the blocks of wood, I'd guess that they're just construction debris - you'll find stuff like that pretty much anywhere that is even slightly hidden - under cabinets, behind drawers, in walls, etc.

Dave

[BEMR]

Hey Tall, my center of cabin 2 air vents always have little or NO air coming out, dealer said that's just the way the do it, makes no sense, how's your airflow from those?

[Mikegjax]

By opening some vents and closing others you are able to increase or decrease airflow to different parts of the RV. At night I open the bedroom and partially close the living area.

[gmccullers]

Tall Guy, with the exception of the wooden blocks, I have the same symptoms. When ours starts cycling it seems to never get the interior cooled down.

[DaveJordan]

Originally Posted by gmccullers

Tall Guy, with the exception of the wooden blocks, I have the same symptoms. When ours starts cycling it seems to never get the interior cooled down.

You might try changing the fan speed from automatic to high (or low) That should cut down on the cycling...

Dave

[Mikegjax]

Facing ceiling vent away from thermostat and adjusting temp one degree up or down usually stops mine from cycling.

[Tall Guy]

I have a reasonable amount of air coming from them. One trick I've tried in very high temperatures (Moab, Utah in July) is to fully open the air vents on the ceiling unit. I use a small piece of cardboard to wedge them open. This helps get the main section of the motorhome cooler, faster.