[Are Gee Specht]

I'm doing it for solar. I live onthe island of Curacao in the carribean see, some 200km noth of the coast of venezuela. It is very hot here the whole year and a lot of sun. And electricity is very costly. My house is allready partially offgrid.
I've allready a chilled watercooled indoor unit from china. Was looking around for a freezer but all conercial freezers have a very small compressor to make ice in 5 sunhours. Had the idea to freeze water in plastic bottles in a glycolwater solution and circulate a loop of glycol in the indoor unit at night. Talked with refrigeration engineer and he told me that i need between 300 to 500l of ice every day to do the job, and it is a lot of electr-energy, like a 2 or 3hp compressor on r290. Thats where the project come to a halt. But lately i bought a 12000btu daikin inverter for my room and uninstalled the old non inverter 12000btu split (r22) wich i'm goin to use for the project. I was wondering to evacuate the r22 and charge it eith r290 and install a 3/8" copper pipe evaporator and txv in a insulated tank. I'll post a pic of the indoor unit.
Maybe the lowered suction pressure damaged your compressor?

 

[jehanzeb]

Interesting project , Good luck. Here is my take on your project. Basically you need around 60 KG of ice to melt in one hour to provide 18000 BTU of cooling. (330 KJ / KG is the latent heat of fusion of ice). For 12000 BTU per hour you need 33 KG of ice to melt per hour. So for a whole night of cooling you need 330 KG of ice (10 hours at 12K BTU). I cant say that a compressor designed for R22 can work for R290 bc of different types of oils and suction and discharge pressures. You copper pipe is ok, but I would recommend a capillary instead of TXV as its simple and probably your unit has one already there. Adjusting the evaporator temp through TXV might be a bit more complicated.
My suction pressure was 35PSI giving me around -8C at the evaporator exit. I think even 3-5 degrees of super heat is good enough, and if you use a accumulator before the compressor that will take care of the slugging.

 

[jehanzeb]

Interesting project , Good luck. Here is my take on your project. Basically you need around 60 KG of ice to melt in one hour to provide 18000 BTU of cooling. (330 KJ / KG is the latent heat of fusion of ice). For 12000 BTU per hour you need 33 KG of ice to melt per hour. So for a whole night of cooling you need 330 KG of ice (10 hours at 12K BTU). I cant say that a compressor designed for R22 can work for R290 bc of different types of oils and suction and discharge pressures. You copper pipe is ok, but I would recommend a capillary instead of TXV as its simple and probably your unit has one already there. Adjusting the evaporator temp through TXV might be a bit more complicated.
My suction pressure was 35PSI giving me around -8C at the evaporator exit. I think even 3-5 degrees of super heat is good enough, and if you use a accumulator before the compressor that will take care of the slugging.