Filter
Top Products
ENERGY STAR Homes Northwest
Geothermal Heat Pump Design and Installation Standards
1
1.0 CLOSED LOOP GROUND HEAT EXCHANGERS
1.1 Installation Personnel and Training Required.
1.1.1 The loop contractor shall have a certified installer (technician) trained by
IGSHPA or an IGSHPA certified manufacturer's training program.
1.1.2 Ground heat exchanger fabricators shall have completed a heat fusion school
in which each participant has performed a heat fusion procedure under direct
supervision of an IGSHPA Association Certified Heat Fusion Technician or
DOT certified heat fusion technician.
1.1.3 Certified technicians shall attend a retraining school annually. A single
failure of a fusion joint will void the certification, and the technician shall be
retested to demonstrate satisfactory performance.
1.1.4 Local and State laws and ordinances as they pertain to buried pipe systems
shall be strictly followed, or the necessary variance obtained from the proper
jurisdiction.
1.2 System Sizing
1.2.1 The recommended method and form for heating and cooling load
calculations is available in the Air Conditioning Contractors of America
(ACCA) Manual J. This or an equivalent method shall be performed using
Component U-values and F-values in the heat loss and heat gain coefficients
that reflect the actual construction of the building. Heating loss calculations
shall be made using 70°F indoor design temperature. The recommended
ASHRAE winter design temperature and cooling design temperature for the
nearest weather station representative of the installation shall be used. Heat
pump system shall be sized to meet or exceed the heating design load of the
house. Installed auxiliary heating shall not exceed 150% of the heating
design load. All supplemental heaters greater than 5 kW shall be staged.
Sizing documentation shall be provided to the ENERGY STAR Homes
Northwest Verifier.
1.3 Thermostats
1.3.1 An electronic thermostat shall be installed to control the heating and cooling
system. Thermostats used for both heating and cooling shall have a manual
changeover feature or heating/cooling lockout to prevent cross-cycling
between heating and cooling.
1.3.2 Heat Pump Thermostat Capability: Heat pump thermostats shall have the
capability of supporting a lock out to limit supplemental heater use. The
thermostat shall have a minimum of two stage heating control.