A/C "quick cycle"

[ingalmi]

Anyone out there that has experienced a rapid cycling a/c (penquin 2). Whisper Quiet system front unit turns on normally and appears to cool normally but after several minutes (fan in auto) the compressor and fan seem to shut down then come back on in several seconds. I'm thinking the return and supply ducts are not properly sealed from each other. I think I need to remove the top unit to see this since it is a Whisper Quiet install.

[chuckster57]

Next time it does it, pay attention to fan speed. In some systems with the fan set to auto the fan will blow on high until the temp is within a few degrees of set temp, then will shut off and resume on low speed. When that happens it sounds like everything is shutting off but just the fan is.

[ingalmi]

I never get to set temperature when it starts cycling. Fan and compressor definitely shut down.

[chuckster57]

Try setting the fan to high or low and see what happens. If it keeps doing the same thing then further investigation is definitely warranted.

Haven't dealt with whisper quiet systems that much, but I would figure the rooftop unit is secured like any other- 4 screws through a plate that thread into the corners of the unit and pull it down to seal it from outside air/water.

[ingalmi]

So I did try both low and high fan settings, the only difference was that the fan stayed on and the compressor cycled. Major difference in the Whisper Quiet installation is that the inside ceiling directly below the upper unit is not where the returns are located. The upper unit is bolted from the top and not through a bottom ceiling plate. The result will be the same if the output and return are not sealed off from each other. Cold air gets pulled back into the return side causing the system to freeze up

[Mandtra]

My dometic 15k acts the same way . Cycles every 45 seconds