I have an open-loop heat pump on a houseboat. The system pumps water thru the system whenever the HVAC unit calls for heat/cooling. The unit is a 3 Ton Carrier and has a water line set with an internal restructor/limiter. The water flow is restricted to approx 6 gpm. The pump capacity is 7.5 gpm max. The system works great for cooling, but shuts down in the heat mode when the inlet water temp drops to approx 48 to 49 degrees because the outlet water temp drops to freezing. The cooling air temp differential across the coil is approx 20 to 22 degrees.
Question: If I remove the restrictor, the flow will increase. Will this have an adverse affect on the cooling mode? By increasing flow, the heating inlet/outlet temp differential should be reduced; this should allow the unit to operate with colder water in the heat mode ... will this have an adverse affect on heating?