After I finished my very first heat exchanger, I
got an offering from a refrigerator repair company. The were willing to help me constructing the
system and filling it with refrigerant. Of course I accepted this offering. So, first of all I
want to thank P. Nieuwkamp and especially M. Nieuwkamp for helping me out. All I did when I was there was
keeping my hands warm in my pocket.
The first thing we did was removing everything from my old R12 compressor unit, except the condenser.
Then, we put a Danfoss R134a compressor unit, type NL7F in place. This is a 150W compressor which is able
to move 182W of heat at an evaporator temperature of -20 °C (ASHRAE rating). The compressor is also
very, very silent. We also replaced the filter/drier. We decided to keep the original capillary tube that
came with the R12 unit.
Wrapping the capillary tube around the filter drier
We also mounted a service valve to faciliate evacuating and filling the system.
Mounting the service valve.
The finished system looks like this. The thick copper tube going from the heat exchanger to the compressor is the
suction line which returns the evaporated refrigerant. The small tube on the right is the capillary tube. Behind
the heat exchanger the condenser is just visible. The red hose on the left is the filling/bleeding line.
The finished R134a system.
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