OK good afternoon my name is Ian ~ from what you have told me it is a control issue rather than that of the heatpump or underfloor heating/water. Could you give me more information about the system such as heatpump manufacturer and electronic control system
It is a Water Furnace E Series heat pump. I do not understand what you mean about electronic control.
If you mean how is it turned on, well, each zone has a DataTherm thermostat which is set to the required temperature.
OK in your original statement you mention that the two zone work independently so obviously the heat pump and underfloor work fine. However the control of the water supply to the zones is not operating correctly, I take it you have zone valves that are controlled by the thermostats?
This is too technical a question for me. Sorry
Is this it?? Is this answering my question?
I can only answer your question based on the information that You supply, you have a technical problem that needs a technical solution. In this case as you are unable to supply the information I can only give you a general area to look in. I would therefore suggest that you get an plumber familiar with heatpump heating systems to look at your problem ~ Ian