CRD Installation Standards & Environmental Compliance 3

Question 1

Which HDPE pipe fusion method is most commonly specified for residential geothermal ground loop connections at header manifolds?

Accepted Answer

Socket fusion

Answer

Socket fusion is the preferred method for joining smaller-diameter HDPE pipes (typically 3/4" to 2") used at geothermal header manifolds in residential installations.

Question 2

What pipe material is required by IGSHPA standards for buried geothermal ground loops to ensure long-term chemical resistance and flexibility?

Accepted Answer

High-density polyethylene (HDPE) SDR-11

Answer

IGSHPA and virtually all industry standards require HDPE SDR-11 pipe for buried geothermal ground loops due to its chemical resistance, flexibility, and longevity.

Question 3

A geothermal installer must document the pressure test results for a closed-loop system. What is the minimum holding time typically required for a satisfactory pressure test per IGSHPA guidelines?

Accepted Answer

30 minutes

Answer

IGSHPA guidelines typically require a minimum 30-minute pressure hold test with no pressure drop to verify loop integrity before backfilling.

Question 4

Which antifreeze solution is environmentally preferred for geothermal ground loops in areas with high groundwater contamination risk?

Accepted Answer

Propylene glycol at 20% concentration

Answer

Propylene glycol is the environmentally preferred antifreeze because it is food-grade, non-toxic, and biodegradable, making it safer near potable water sources.

Question 5

When installing a pond loop geothermal system, what is the minimum recommended pond depth per IGSHPA guidelines to ensure adequate heat exchange?

Accepted Answer

8 feet

Answer

IGSHPA recommends a minimum pond depth of 8 feet to ensure the loop coils remain below the thermocline and avoid thermal depletion in cold weather.

(CRD) Certified Residential Geothermal Designer Practice Test

(CRD) Certified Residential Geothermal Designer Practice Test

CRD Installation Standards & Environmental Compliance 3