40 F Spring for a water-source heatpump

[microHydro]

I've got a 3.3 gpm spring that flows 40 F water. I'd like to use this for heating with a small water-source heatpump. Cooling the spring water all the way to 32 F yields a heat flux of about 13,000 btu/hr. What kind of evaporator design could accomplish this?

[geodude]

Depending on your thermal extraction from the water ( delta T ) and speed of the water through your heat exchanger, you may freeze the water in your heat exchanger.

[james122964]

I've got a 3.3 gpm spring that flows 40 F water. I'd like to use this for heating with a small water-source heatpump. Cooling the spring water all the way to 32 F yields a heat flux of about 13,000 btu/hr. What kind of evaporator design could accomplish this?

what part of the country are you in? my spring runs 58.
I have only 2 gallon per min though.

Jim