CRD Installation Standards & Environmental Compliance 4

Question 1

What is the required flushing velocity in HDPE ground loop pipes during system purging to ensure air removal per IGSHPA standards?

Accepted Answer

2.0 ft/s minimum

Answer

IGSHPA standards require a minimum flushing velocity of 2.0 ft/s in ground loop pipes to achieve turbulent flow and effectively purge air from the system.

Question 2

Which environmental concern is specific to open-loop (groundwater) geothermal systems that does NOT apply to closed-loop systems?

Accepted Answer

Groundwater discharge permit requirements

Answer

Open-loop systems that discharge groundwater to surface water or injection wells require discharge permits under the Clean Water Act's NPDES program, unlike closed-loop systems.

Question 3

In a residential geothermal installation, what is the primary purpose of installing a flow center with an integrated purge cart?

Accepted Answer

To flush, charge, and purge air from the ground loop during commissioning

Answer

The purge cart integrated into the flow center allows technicians to flush debris, remove air, and charge the ground loop with antifreeze solution during system startup.

Question 4

Which state regulatory body most commonly issues drilling permits for vertical geothermal boreholes in the United States?

Accepted Answer

State Water Resources Control Board or equivalent

Answer

State Water Resources Control Boards or equivalent agencies (e.g., state DNR, DEP) typically regulate vertical well drilling including geothermal boreholes to protect groundwater.

Question 5

What is the acceptable pressure test value range for a newly installed residential geothermal closed-loop system before backfilling?

Accepted Answer

75-100 PSI with no drop over 30 minutes

Answer

IGSHPA guidelines recommend pressure testing at 75-100 PSI (not to exceed pipe pressure ratings) with zero pressure drop over 30 minutes to confirm loop integrity.

(CRD) Certified Residential Geothermal Designer Practice Test

(CRD) Certified Residential Geothermal Designer Practice Test

CRD Installation Standards & Environmental Compliance 4