INCREASE COP of 18 % - need expertise

Dear,
we just finish the certification EN14511:2011,
Temperature AIR is 7 degree and the cop is measure to heat the water from 35 to 40 degree.

we want to increase the COP of 18% for our HEAT PUMP WATER. We want to increase from 2.76 to 3.25 or more for the condition measure in the standard.
Attachment 9490

the gas is R410 -600 grammes

we want to optimize the COP for air 7 degree and heating 35 degree, even if we degrade other range of heating. but we need to reach 60C minimum for 7C.

we can examine many axes:
- change gaz or combination with an other
- add sub-cooler - exchanger (simple by 2 small pipe inside a bigger)
- increase length of some pipe or diameter
- other solution

please found the information here:
Attachment 9491

Sorry my friend your so far behind, 3.25, is shocking for those conditions.
Lets point you in the right direction.
You are loosing a lot of heat energy, "where"? and how are you going to fix it?

Dear mad fridgie, i agree, i want to have no loss of heat energy except in the ballon.
I want to optimise the transfer all the energy to the water.

the caracteristic of our compressor is this:
Attachment 9492
and during the test we have:

HEATING CAPACITY = 2485W
HEATING POWER CONSUMPTION(W)= 900W
Current(A)= 3.95

So where are you loosing lots of heat?

Look at the picture and feel with your hands

Yes mad fridgie
can we please have some more data on this machine like compressor data and heat exchangers etc. I think if you changed to R22 for a heat pump gas you would get better results but that gas was good 10 years ago and perhaps not so politically correct today. A sub cooler heat exchanger will increase out put only if the compressor has the capacity for the conditions. You could also experiment with COP measurements with an increase and decrease of the 600 Gms of R410a of 10% and check response with either EEV or some control over superheat at metering device for the changed conditions - either load or ambient.

Thanks Tesla,

for the advice, the data of the compressor is in my second post above. I want to make some simulation before changing. Do you know some expert than can estimate the gain of the cop, before do some change or advice me what superheat or sub cooler i can use for this specific application.

Another question is really, the 4 way valves is an advantage in this case (compressor is below 1KW and no reversibility here) ? if any body can reply

another way i found in this article:

Attachment 9493

IS anybody have change an TEV by an EEV and see an increase of COP very important?

First of all,
There is a lot of figures missing before we can tell you much...
What is your;
Discharge pressure?
Suction pressure?
Subcooling?
Superheat?
Air temp on evaporator?
Air temp off evaporator?
Air volume through the evaporator?
Water temp on condensor?
Water temp off condensor?
Water flow through condensor?

Generally an EEV will only give marginal savings and then only at the "ends" of the design envelope.
The 4 port valve is only needed if the system is reversible, if it never will cool the water and heat the air then it can be removed but on the other hand should have no impact on your COP what so ever providing the system is correctly designed.

:cool:

.

Best employ someone who knows about refrigeration.
It is very clear from the data given that you have a number of issues and that you do have limited understanding of the design and mechanical process.
Focus on base principles before yous start looking at specifics.
There is a saying "you can not make a silk purse out of a sows ear"

Dear mad fridge,

thanks for your advice, and i agree. If some company or person have done comparable study and are capable and interested by this challenge, i will be happy to contract them for a mission. Please send me proposal privately.

thanks.