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ASU ASHRAE
06-04-2009, 11:30 PM
hi,
We are designing a heat pump to aid a domestic water heater for our senior design project at Arizona State University and I am having trouble finding a compressor that will work for my needs.
here are the specs. it needs to handle:

refrigerant: r410a
Freq: 60hz
voltage: 120 V
Capacity: 5585.17 Btu/hr
pressure: from 159 to 525 psi
efficiency: around 70%


Thanks,
Paul.

nike123
07-04-2009, 03:42 AM
Any rotary compressor for modern split system AC will do that pressures/temperatures. Check Toshiba, Daikin, Matsu_s_hita, Sanyo, Mitsubishi spare compressors for their split system AC-s of that capacity.

desA
07-04-2009, 06:04 AM
Your isentropic efficiency at 70% is probably asking for a lot - nice if you can get there. Most would be closer to the 60% mark at high temp.

Why R-410A for a water-heating heat-pump? Don't you need a fluid with a higher critical temp? What temperature do you want to heat your water to?

Have you looked into alternative refrigerants?

amitsaxena
07-04-2009, 10:47 AM
Dear You can look for samsung rotary comporessor
G4C065JU, slightly higher in capacity.
thanks
amit

ASU ASHRAE
07-04-2009, 09:01 PM
Amit,
Thank you for the response, It has been really helpfull. I have a couple of questions for you:
1) is the fact that the compressor is for 50Hz instead of 60Hz something I should worry about? I don't think that frequency will work here in the US

2) as far as the capacity being higher, can I adjusted so that it works at the capacity that I want or does it matter at all?

for DesA,

R410a is a requirement for the design. This is because we are part of the energy and environment concentration for ME and ASU requires us to use that type of Refrigerant. Trust me, if we could use R-22 instead we would've already be done with the whole thing!!

For Nike123,

Thanks for the name brands, I'll check them out right now.


Thanks for your suggestions.

Paul.

desA
08-04-2009, 12:55 AM
for DesA,

R410a is a requirement for the design. This is because we are part of the energy and environment concentration for ME and ASU requires us to use that type of Refrigerant. Trust me, if we could use R-22 instead we would've already be done with the whole thing!!

No need for R-22 - I don't touch it in my heat-pumps. Why not use R-134a? Have a look at its critical temperature compared with a blended refrigerant (R410a).

For a hot-water heat-pump, you need a refrigerant which operates some 'distance' from its critical temperature.

:)

amitsaxena
08-04-2009, 05:07 AM
DearASU,

1. What i feel, as the motor is designed for 50Hz but it can also be used in 60Hz it will not make much difference as the comp is slightly overdesigned.
2.Yes capacity can easily be adjusted with the help of Expansion valve, hence if you select this comp and use the exp valve which is only of capacity required, then comp can not deliver more.
3. My suggestion is that as your usage is for heat pump so i would recommend R 407C.

Thanks
Amit

ASU ASHRAE
18-04-2009, 09:28 PM
amit,

I have been trying to get pricing for the samsung compressor model G4C065JU you gave me and I can't find any dealers that would carry that. Do you know of any websites or catalogs I might be able to get that price from?
thanks,
Paul