On Monday, June 4, 2018 at 3:12:56 PM UTC-4, wrote:
I have basement with over 13,000 square feet w/ 9 feet to upper floor.
When temperature is 0 F outside basement is in low 30's.
Water temperature is in low 40's.
I am wondering if there is enough heat in basement floor & walls to heat 1,000 square feet on upper floor with heat pump.

If you're proposing to try to extract heat from the basement and use it
upstairs when the basement is in the low 30s, it's probably not going to
work. The system won't have to run very long before the basement air
temp drops, you're turning it into a freezer. And the lower it goes,
the less efficient a heat pump is. That is unless the basement is
much larger than the 1000 sq ft. What other choices are there for heat?