Energy Tech Laboratories Homes Northwest manual 2.0PIPE PLACEMENT AND BACKFILLING

1.8.4No visible leaks shall occur within a 30 minute period.

1.8.5All fusion joints and loop lengths shall be visibly checked to verify that no leaks have occurred due to fusion joining or shipping damage.

1.8.6Flow rates will be compared to calculated values to assure that there is no blockage or kinking of any pipe.

1.8.7A minimum velocity of 2 ft/sec in each piping section shall be maintained for a minimum of 15 minutes to remove all air.

1.9Piping arrangement

1.9.1All piping arrangements, including pipe diameters, header arrangements, parallel and series loops, reverse returns, etc. shall conform to manufacuturer’s recommendations and approved design criteria. Field substitutions shall not be allowed without prior approval.

2.0PIPE PLACEMENT AND BACKFILLING

2.1.Horizontal Systems

2.1.1Sharp bending of pipe around trench corners shall be prevented by using a shovel to round corners. Manufacturer's recommendations shall be followed.

2.1.2Backfilling procedure will include prevention of any sharp-edged rocks from coming into contact with the pipe by removal of the rocks before backfilling, backfilling through a coarse screen for a 6 inch cover, or use a 6 inch cover of sand. Clods resulting from use of a backhoe shall be broken up so air pockets formed around the pipe will not reduce heat conduction between the earth and the pipe. In some types of soils, wetting or flooding may be required.

2.1.3Horizontal return bends shall be backfilled by hand to properly support the pipes and prevent kinking.

2.2Vertical Bore Holes.

2.2.1The dry section of a vertical bore holes shall be backfilled to ensure good heat transfer. Local and State codes as to backfilling requirements shall be followed. In some cases a bentonite grout/slurry will be required.

ENERGY STAR Homes Northwest 4

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