The heat pump most suited to each situation is determined by a number of factors. When combining the heating for a swimming and underfloor, sizing priority is given to the area has the greatest load requirement. These factors include things such as; surface area of the pool, whether the pool has a cover and the time it is covered, underfloor area, building structure and local temperature and weather conditions.

For more information about heat pump sizing please contact Hot Water Heat Pumps. As a general guide to heat pump requirements for an extended season of swimming from mid October to mid April and underfloor area based on modern insulated houses with a 2.4m stud as listed:

17KW POOL & 11KW UNDERFLOOR HEAT PUMP - 7GP17U11-1 & 7GP17UB11-1 (SINGLE PHASE) & 7GP17U11-3 & 7GP17UB11-3 (THREE PHASE) 

• NOTE: Ub model includes buffer tank & circulation pump
• Residential Pool (up to 4 hours per day uncovered) with a surface area up to 65m² for most of the North Island, up to 60m² for the Central North Island and South Island.
• School Pool (up to 6 hours per day uncovered) with a surface area up to 48m² for most of the North Island, up to 43m² for the Central North Island and South Island.
• Commercial Pool (up to 12 hours per day uncovered) with a surface area of up to 38m² for most of the North Island, up to 22m² for the Central North Island and South Island. 
• Underfloor area of up to 220m² (providing 50 Watts/m²) for Northland, Auckland, and Coastal Bay of Plenty.
• Underfloor area of up to 169m² (providing 65 Watts/m²) for Hamilton, Gisborne, Taranaki, Coastal Hawkes Bay and Wellingon.
• Underfloor area of up to 129m² (providing 85 Watts/m²) for the Central Plateau and South Island. 

20KW POOL & 9KW SPA HEAT PUMP - 7GP20U14-1 & 7GP20UB14-1 (SINGLE PHASE) & 7GP20U14-3 & 7GP20U14-3 (THREE PHASE)

• NOTE: Ub model includes buffer tank & circulation pump
• Residential Pool (up to 4 hours per day uncovered) with a surface area up to 65m² for most of the North Island, up to 60m² for the Central North Island and South Island.
• School Pool (up to 6 hours per day uncovered) with a surface area up to 48m² for most of the North Island, up to 43m² for the Central North Island and South Island.
• Commercial Pool (up to 12 hours per day uncovered) with a surface area of up to 38m² for most of the North Island, up to 22m² for the Central North Island and South Island. 
• Underfloor area of up to 276m² (providing 50 Watts/m²) for Northland, Auckland, and Coastal Bay of Plenty.
• Underfloor area of up to 212m² (providing 65 Watts/m²) for Hamilton, Gisborne, Taranaki, Coastal Hawkes Bay and Wellingon.
• Underfloor area of up to 162m² (providing 85 Watts/m²) for the Central Plateau and South Island.

Ideal applications

• Swimming pool and underfloor
• Indoor pool heating and air heating

All heat pump models carry a comprehensive two year parts and labour warranty, including the compressor, evaporator coils, heat exchanger and refrigeration systems. The titanium tube within the heat exchanger is covered against corrosion for 30 years for residential use and 10 years for commercial use.

Heat pump water heaters are fitted with protection systems to prevent damage in the event of a malfunction. Such as a flow switch to ensure the heat pump cannot operate without water flow and other refrigeration safeties. If a problem is identified, the unit automatically shuts down before damage can occur.