Water heater using heat pump

[ctscasemod]

Hi guys,
I've serached the forum but all the post regfarding this were either too old or "closed"

Now the question is: I want to heat wather at home using a compressor. The kind of compressor used in refrigirators 1/4 or 1/6HP.

I think the electric water heaters are way to much inneficient, espeacialy in sumer when you use power to cool down the house, so you are wasting heat that otherwise could be used to heat water.

I need about 50liters capacity.

Questions:

Which is the best temperature for the wather / Condenser to have optimal performance? I need about 40-50Degrees Celcium. Should this be OK?

Wich size for the capilar tube?
How many gas should I put? 70PSI is ok?
Wich is the best temperature for the evaporator so that it doesn't get full of ice? I live in Portugal in a climate were ambient temperatures don't go much colder that 5Degrees Celcium, while at summer 40Degrees are normal. The Evaporator has a FAN blowing air.

The wather should not take more that 1,5Hours reaching 35Degrees. I usualy arrives home between 10 and 20 Degrees so no big problems here

Wich Refrigirant should I use? I usualy stick with R134, althought sometimes I find old compressors (R12) and like to retrofit them with R407C because of the mineral oil. Much better in my oppinion that the R134 easter oil that gets full of moisture. Are this OK? If not wich is the best alternative? Pros and Cons of each one.

And yes, opinions and thoughts are welcome.

Thanks, Carlos

[Tesla]

Hi Carlos
Welcome to the forum. Not to sure ablut the size but I think 1/2 - 3/4hp aircon compressor, not a refrigerator compressor. R22 works best for a heat pump. And if you can preheat the water through heat exchanger in waste pipe or coil of black plastic pipe on the roof you could halve the energy used. A scroll would be the best type of comp, then rotary, piston. If you search the posts you will find other helpfull stuff like how to calculate the heat load, then sizing compressor, cappillary etc. Good luck

[Magoo]

check this site,,, www.waterheating.co.nz