First of all, i appologize in advance for my bad english, i don't have any problem to understand it but i have some difficulties when it comes to talk or write
My question is about the hunting problem for electronic expansion valve in a heat pump.
A couple of days ago, i acquired a reversible air/water (the water circuit is in the condenser side) heat pump in wich i wanted to perform some test. In those test, i cheated about the ambiant and the secondary fluid temperature in a way that it's impossible for the ambiant temperature (or starting temperature for secondary fluid) to reach the setpoint indicated to the heat pump (in fact the thermocouple that measure the ambiant temperature is in an independent room and the secondary fluid is not in a close circuit, i always put new water).
What i can't understand is, since the heat pump is not able to reach those setpoints, it should work with a maximum refrigerant fluid flow. then, how is it possible to observe oscillations due to the eev hunting since the heat pump is not working in partial load?
it's clear that i misunderstood something on the theory of the system, if anyone can help me i will be forever grateful
I believe to answer your question. A lot more info about what the leaving and entering fluid and air temps were would be needed.