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randen · 02-15-13, 04:57 PM

The new homemade GSHP is being tested for leaks both refrigerant and the water side for the heat exchangers. Everything looks good. The varible frequency drive is programmed for basic function. For this application this particular VFD wouldn't let me power the 3 ph compressor with supplying single phase only. In the basic circuit design of the VFD the line power 240 VAC 60Hz is applied to a bridge rectifier to 360VDC approx. on the DC buss and from there the munipulation of the Voltage, Current and Frequency. The manufacturers must want to confirm with this model they have the 3 legs for the 3 phase. VFD's can be purchased that will operate from single to 3 ph.

The VFD has so many cool features from timers to relays to many operation profiles as well as Analog input for speed control. The VFD even has a counter for time operating and # of cycles. Can hardly wait to play with it but will have wait until its installed with loopwater running through the HX's

The compressor is rated 240 V 3ph 17A running load. Thats 5 Ton 60 KBtu if .you check a single phase compressor of the same capacity you will see they almost double the amount of run current. I'm expecting it should be no more expensive to operate than the 3.5 Ton single phase that I removed.

I wish I had thought about this when we had the geothermal units installed in my home. We did talk about that option because we are nearing the capacity of our 100A service to the house. We thought about changing the service to the house to 3 phase and installing a small step down transformer. With this we could have installed 3 phase heat-pumps that operate for near half the cost. Our service line to the house is quite long so we do experience a little line loss.

In my 5.0 Ton build I included a suction line heat exchanger. This is something that Jeff and Mikesolar have been doing some work on. I had the bits and pieces it took a little extra time but now its included. I just worked with the space and pieces I had and its 1.125 dia x 7" lg. around the 7/8" suction tube. Hopefully we will gather a little more efficiency.

In the photo's you will notice a nice trick to stop tubes from vibration. Using a tie-wrap and a section of rubber tube you can lash the tubes together with the rubber tube between simple & effective. In the top veiw you will see the modified TXV with the old gate valve handle as well as the sight glass. The sight glass is really a must have. With it you can confirm the condensor is full of liquid refrigerant. It is suprising how sensitive the TXV's are. Just a 1/8 of a turn can alter the pressure alot. The cheapy foam pipe wrap is more for the prevention of condensation than heat loss. Without this the floor around the GSHP gets wet with condensation. The wrap also helps with noise reduction. The other copper tubes will have the insulation slipped on when the GSHP has finished operating for the probationary period.

Randen

02-15-13, 04:57 PM	#23
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	5.0 Ton build The new homemade GSHP is being tested for leaks both refrigerant and the water side for the heat exchangers. Everything looks good. The varible frequency drive is programmed for basic function. For this application this particular VFD wouldn't let me power the 3 ph compressor with supplying single phase only. In the basic circuit design of the VFD the line power 240 VAC 60Hz is applied to a bridge rectifier to 360VDC approx. on the DC buss and from there the munipulation of the Voltage, Current and Frequency. The manufacturers must want to confirm with this model they have the 3 legs for the 3 phase. VFD's can be purchased that will operate from single to 3 ph. The VFD has so many cool features from timers to relays to many operation profiles as well as Analog input for speed control. The VFD even has a counter for time operating and # of cycles. Can hardly wait to play with it but will have wait until its installed with loopwater running through the HX's The compressor is rated 240 V 3ph 17A running load. Thats 5 Ton 60 KBtu if .you check a single phase compressor of the same capacity you will see they almost double the amount of run current. I'm expecting it should be no more expensive to operate than the 3.5 Ton single phase that I removed. I wish I had thought about this when we had the geothermal units installed in my home. We did talk about that option because we are nearing the capacity of our 100A service to the house. We thought about changing the service to the house to 3 phase and installing a small step down transformer. With this we could have installed 3 phase heat-pumps that operate for near half the cost. Our service line to the house is quite long so we do experience a little line loss. In my 5.0 Ton build I included a suction line heat exchanger. This is something that Jeff and Mikesolar have been doing some work on. I had the bits and pieces it took a little extra time but now its included. I just worked with the space and pieces I had and its 1.125 dia x 7" lg. around the 7/8" suction tube. Hopefully we will gather a little more efficiency. In the photo's you will notice a nice trick to stop tubes from vibration. Using a tie-wrap and a section of rubber tube you can lash the tubes together with the rubber tube between simple & effective. In the top veiw you will see the modified TXV with the old gate valve handle as well as the sight glass. The sight glass is really a must have. With it you can confirm the condensor is full of liquid refrigerant. It is suprising how sensitive the TXV's are. Just a 1/8 of a turn can alter the pressure alot. The cheapy foam pipe wrap is more for the prevention of condensation than heat loss. Without this the floor around the GSHP gets wet with condensation. The wrap also helps with noise reduction. The other copper tubes will have the insulation slipped on when the GSHP has finished operating for the probationary period. Randen Attached Images Last edited by randen; 02-15-13 at 05:02 PM..