Method for testing an earth tap heat exchanger and associated apparatus

A method for installing a ground-coupled heat pump apparatus comprising the steps of:

• providing at least one earth tap heat exchanger comprising electrically conducting tubing having an electrically insulating layer covering an exterior thereof;
• positioning the at least one earth tap heat exchanger in soil or water;
• connecting the at least one earth tap heat exchanger in fluid communication with associated fluid lines of the heat pump apparatus;
• and
• providing electrical isolation means for electrically isolating the at least one earth tap heat exchanger from electrical ground.

A ground-coupled direct expansion heat pump apparatus comprising:

• a first heat exchanger;
• at least one earth tap heat exchanger for positioning in soil or water and comprising electrically conductive tubing and an electrically insulating layer covering an exterior thereof;
• electrical isolation means for electrically isolating the at least one earth tap heat exchanger from electrical ground for permitting measurement of an electrical resistance between the electrically conducting tubing and the soil or water to determine if the electrically insulating layer has an undesired opening in a portion thereof thereby exposing an adjacent portion of the electrically conducting tubing to the soil or water as indicated by a relatively low electrical resistance measurement;
• and
• a compressor for circulating refrigerant through said first heat exchanger and said at least one earth tap heat exchanger.