Week90 - 30Jun 2003

As with everything, laying the ground loop needs planning. The trick is to arrive back at the entrance/exit point to the house with the right amount of pipe. For the 1st loop I use a combination of  a single pipe in a single trench and the method Ice Energy call "slinky" which involves loops of 1m diameter 0.5m apart. The latter method obviously requires a wider trench (1m) but (using Pythagoras) you can lay 4m of pipe per linear meter. This is a more efficient use of the ground available. After some careful calculations I conclude that the 2nd loop must be all "slinky".

First loop laid ready for filling & pressure test
The "slinky" laying method
The pipe is filled with water (rain water of course!)
The water must run for 10 mins to remove all air. I run the water back into a downpipe connection & thus back into my water tanks. No waste!
The pipe is then pressurised to 10 bars and left for 20 mins. Pressure may drop to 6 bar as the pipe expands. Mine held 7.5 bar
The pipe is then covered in sand and back-filled. Not rocket science!

With the wettest weather for months, I decide to enlist some help for a couple of days with the 2nd loop to ensue we are ready for the commissioning scheduled for Tue 8th July.

Digging the 2nd loop begins
and we start the clear-up!
The heat pump is now ready for the final connections