Air-to-water heat pumps and water-to-water geothermal heat pumps provide warm water for space heating, domestic water heating, and chilled water for cooling. Switching a hydronic heat pump system from space heating to cooling and vice versa seasonally is relatively simple. The system operating mode is changed at the thermostat or a dedicated system mode switch with heat, off, and cool settings.

Last month, we began discussing the HVAC system installed at my church’s newly-constructed parsonage. In this month’s column, we’ll complete the picture.

An installer is asked to provide a 4-ton-rated (48,000 Btu/h) geothermal heat pump system that can provide space heating and domestic hot water.

Weil-McLain’s 95% AFUE high-efficiency ECO Tec boiler features heat only and combi versions for all residential space and domestic hot water heating, the company explains.

In last month’s column, I presented a “template” for a system that provides space heating, cooling and domestic water heating using a cold climate air-to-water heat pump as the primary heat source, and the sole source of chilled water for cooling.