R407a in R-22 retrofits?

[ktice]

I saw a topic on this else where and I wanted to see what you all thought. Is anyone using R407a in the R22 retrofits?

[AndyHX]

hi there , i have not used 407a but have converted a swimming pool heatpump system to 417a , slightly lower super heats , much lower discharge temp (from 90 to 68 ) so very happy , oh and lower running amps , all good so far.

[Lodiev]

I am in a similar dilemma now with all our vessels witch are on R22 gas. We have to phase out R22 in 3 years from now but being a pro active guy i want to start now. The problem is that i am not sure to what gas i must change, sure there are a couple of options but look at the T/P and capacity charts and make a decision, and not to speak about the oil and o-ring changes that needs to be made. We have massive plants on the vessels witch take up to 4 tons of gas per vessel and one screw uses 200 Lt of oil with 4 screws per vessel. These vessels go out on sea for 40 to 50 days and only return to re fuel and unload the catch, so there is no time for error on the plants at sea. What to do ?????????????

[nevgee]

hi there , i have not used 407a but have converted a swimming pool heatpump system to 417a , slightly lower super heats , much lower discharge temp (from 90 to 68 ) so very happy , oh and lower running amps , all good so far.

Andy,
You say the discharge temps are lower, by 22deg C?
That's a significant drop in temp. Being a swimming pool heat pump are you just looking to maintain the dehum process without any concerns over heat recovery to the pool /Air side. Which would be a lower grade of heating if the discharge temps are lower? Do you then assume the auxiliary heating will take up any slack on the heating processes?

[AndyHX]

yes the discharge temperature (discharge super heat) is much lower but condensing saturated temp is very close to r22 temperature , so benefical for longevity of oil in system and life of compressors. Capacity drops 5 % but use less power and increase in cop of about 15% , swings and roundabouts i suppose , has to work longer to achieve temps but at lower costs.