Flow control valve and spa recirculation system with heat pump using the valve

In a bathing installation including a tub for holding bathing water and including an water inlet port and a water outlet port, a recirculating water flow path connecting the tub inlet port and the tub outlet port, a water pump connected to the tub output port to pump water through the water flow path, and a water bypass path in the recirculating water flow path configured to divert water to the inlet port, the combination comprising:

• a heat pump connected in the water flow path for temperature conditioning the bathing water;
• and
• a flow control valve positioned in the recirculating water flow path downstream of the water bypass path and upstream of the heat pump, the flow control valve configured to dynamically regulate water flow through the valve in dependence on the water pressure applied to the valve, the flow control valve to operate between an open state and a closed state, as water pressure increases to a value that causes the valve to be placed in the closed state;
• wherein as the water pressure applied to the valve increases, an amount of water diverted to the water bypass path increases to reduce the water flow to the heat pump, the valve serving to maintain the water flow to the heat pump to a given flow for efficient heat pump operation, and to prevent the water flow to the heat pump from exceeding a predetermined maximum water flow that would lead to heat pump damage.