The heat pump in our unit isn't loud. Here are some things to know about the heat pump. It is basically the AC working in reverse. The cool air is sent to the outside and warm air to the inside. It is an electric heater that you can use so you don't need space heaters or use the furnace when temps are mild. The heat pump is not a substitute for the furnace. It is a supplement to it.
The heat pump comes on when the t-stat is set to within 5 degrees of the interior temp. If the spread is more than 5 degrees, the furnace kicks on first to bring the interior temp up to within the 5* then the heat pump takes over. Also, if you have the heat pump running and the temps outside dip below 40*, the furnace automatically kicks on.
As long as you know what the heat pump is, how it works and it's limitations, you'll be happy with it. We live in Texas and camp year round. It rarely gets really cold so the heat pump is great because no more space heaters, and a comfy trailer using CG electricity versus costly propane.
2016 North Point 377 RLBH
2006 Ford F350 Lariat, CC, 6.0PSD, DRW, SCT tuner, air bags, bullet proofed