I have a new build with pex pipe in the slab and manifold etc plumbed for a GSHP. Unfortunately I have been caught out by weather/contractor so have been unable to dig trenches for the loop before our wet weather starts-making trenching difficult. My wife is not really happy that we don't have underfloor heat yet! For a temporary fix (until I can get the trenches dug) I am thinking that I could either:
1/Connect the GSHP to the floor and plumb a heat exchanger where the ground loop would normally be and on the other side of the heat exchanger connect that (with a circulating pump) to the house hot water cylinder (which obviously has hot water). The GSHP should then extract heat from the hot water cylinder (which is large and also solar heated as well as electrically)
and heat the floor. This would require the least replumbing when I get around to putting the loop in.
2/Connect the heat exchanger with pump to the hot water cylinder and on the other side of the heat exchanger connect the floor (with an additional pump). This maybe more efficient? But would require an additional pump that I am not sure that I would reuse.
