We have a communal geothermal well for 10 townhomes.
Our unit has Envision Waterfurnace and a 120 gallon tank it heats. The tank goes to hot water and radiant heat.
When we moved in, Waterfurnace was working smoothly, gradually increasing the noise until the temperature is reached. The temp was set to 115F. The winter came and with it came the freeze protections. After some maintenance magic: purging air, reloading refrigerant and setting the geothermal well pumps to max, setting the target temperature to 108F the unit started to work uneven. The installer came again, but "found nothing wrong" with the heat pump.
However I feel there might be something wrong.
I'd like to get your opinion. The data I gathered:
TED says the unit consumes power like this:
(HeatPumpLoad.jpg) (small spikes).

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The pump sounds like this: http://www.youtube.com/watch?v=AziJWMHt6N8
the noise increases near 15th second and 1:47.
Any suggestions are appreciated.