Is possible to add next evaporator to air>water heat pump and make air+ground>water ?

[medusa]

Hi I want to ask if is it possible, it is just hypothetical now

I want to use cheap air>water heat pump (designed for pool heating) to prepare hot water and heating house (45 *C 110 *F should be fine)
It could work well down to 5-10 *C (40-50 *F), it have no defrosting
I have an idea to add plate heat exchanger to evaporator (between expansion valve and current evaporator) and "heat" it with ground collector (which gives stable water temp 0-5 *C (30-40 *F) whole year)
So at low temperatures it will work from ground and with rising outdoor temperature will use more and more air evaporator to increase efficiency

Do you thing could it work ?

[research]

Hi. better would be to parallel the evaporators and control them with solenoids. If they are in series, there will be issues with liquid distribution and pressure drop.

This company has a dehumidifier heat pump but if you take out the reheat coil and used the condenser to heat domestic water it would be what you are describing.
http://www.desert-aire.com/index.php?option=com_content&task=view&id=282&Itemid=117

Note that the condensers are in series, but the evaporators are in parallel. Different operating characteristics.

Check your local plumbing codes for the type of condenser. Many require 'double wall vented ' construction of condensers used to heat domestic hot water. (it may already be part of the pool heater)

[medusa]

I have an idea to connect it like this image
6676
Fluid is distributed by gravity
So water evaporator could be flooded when not used
And when is used, then air evaporator could be used to heat steam with output air from ventilation to increase performance
It should require just increase amount of refrigerant