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rgs5081
17-08-2014, 06:27 AM
hai,
I want to know the pumping rate of a 1.5 ton AC compressor,
how much kg of gas is pumped per minute .
please watch this video

https://www.youtube.com/watch?v=qTYGloPSGec

and help design one with the capacity of storage accumulators for liquid and evaporated refrigerant gas
thank you

R.Gnanasekaran

PRESS
17-08-2014, 07:35 AM
Quite some fancy concept there. Do you have any idea if anyone is using that concept yet? Pumping rates for compressors vary from one compressor to the other as follows:

1. They differ from one manufacturer to the other
2. Type of refrigerant used
3. The frequency of your power source

you need to check on specifications by different manufacturers for you to zero in on the flow rate you require.

mikeref
17-08-2014, 11:03 AM
Original poster is from India. There is at best..8 hours of usable sunlight per day (if solar panels tracked the sun for maximum effect) so a solar system would have to be sized for at least 3 times the energy consumption of an a/c in a 24 hour period.

Focusing on Battery bank.

There is the maximum recommended amount of power that can be delivered without shortening the deep cycle batteries life.... Batteries have a long memory and they charge interest when being recharged. Approximately 20 %. Inverters charge another...ah....possibly 10%...depending on size/ usage and quality.

Liquid storage.

Liquid Refrigerant storage during the day, as per video...without sound :rolleyes:...will lose pressure as over night temperatures drop. Loss of pressure= less differential between High and low.
Loss in pressure from storage "Tanks" is energy lost. Significant reduction in cooling availability.

mikeref
17-08-2014, 11:17 AM
Er...It's Sunday night and i'm on the Morgan's.:cool:

Started my Sunday with an open drive compressor changeover to save 40K or so worth of packaged meat at my Favourite Abattoir. Damn thing put up a good fight on it's 4 belt drive.
:off topic:

monkey spanners
17-08-2014, 11:45 AM
I think it would cost too much to fill it with refrigerant, and if it leaked it could suffocate the people in the house!

Think it would be better to use excess energy to cool water thats stored in a big tank and use that at night to cool the building maybe with a thermosyphon set up as would not need too much power to run.

rgs5081
17-08-2014, 04:40 PM
thanks again, to my knowledge i haven't seen such a thing. from the feed back only i can learn something.how much of gas in kg/min approximately a 1.5 ton AC compressor pumps will be my starting point and then shall decide what to do.

PRESS
17-08-2014, 05:13 PM
Which gas within what temperature parameters at what pressure? Thats whats required to calculate the answer you require.

The MG Pony
18-08-2014, 02:51 PM
That idea is hidious in concept and many problems in practical usage. Much better to freeze water then let this cool during night when little heat will be added to the room from out side!

rgs5081
20-08-2014, 05:28 PM
if it leaked it could suffocate the people in the house!

i will take note of this point, very important,

thanks

rgs5081
20-08-2014, 05:33 PM
if it leaked it could suffocate the people in the house!

i will take note of this point, very important,

thanks

rgs5081
20-08-2014, 05:39 PM
Which gas within what temperature parameters at what pressure? Thats whats required to calculate the answer you require.

we are using R22 gas and the room temperature range is 34 deg C to 40 deg C , 18 deg C if reached would be enough.

The MG Pony
23-08-2014, 04:42 PM
I will repeat as I feel it is needed.
1: It will not work, you'd need way more volume than you can imagine
2: Way to much liquid R22 will be in the system, this is a disaster in the making, it will end badly for all

3: when it goes off it will suffocate or burn all in or near vicinity of the system

Now much more safe and practical system is to freeze 1K L of water in a well insulated tank (This is one ton of ice), then circulate this water in your heat exchanger through the night, the compressor will only then need to come on every so often to help chill the water till morning with vastly reduced duty cycle.

This keeps the gas charge low, and far greater safety should a leak occur.

An auto motive compressor on average is rated for 2tons at rated RPM, it will require apx 2.5Hp at full pumping power at its rated evap temp (if I recall the average is 35-40degree F evap)

So with a correctly sized solar array running it full out should easily freeze the water during the day after the room has reached desired temp, this will allow for a smaller battery bank as well as the ice is doing the bulk of the work for you. The tank can be placed in a pit with large amounts of insulation (Saw dust, straw, glass fibre, then cover to protect from out side moisture then rebury it with dirt, insulate the pipes well.

This method is superior in efficiency and safety compared to the above proposed idea.

The MG Pony
23-08-2014, 04:47 PM
you will only need one pump running all the time to circulate a water glycol mix from an hx in the tank to the hx in your window, this pump will only draw apx 25w to 35w to perform this job.

any leak in this circuit will be very safe if you use propylenglycol.

I am certain water and glycol are much easier to acquire then R-22 and much cheaper in cost as well. There for the cost of the system will be greatly reduced, greater safety, greater simplicity, you save on the over all project in many ways.

Put these savings to use by adding better insulation to the room that you are trying to cool, further reducing the load on the ice bank thus saving energy more directly.

Saving energy costs fractions of that to make energy, it is the first rule of when designing a solar system.

xxargs
23-08-2014, 05:24 PM
For 5 kW cooling capacity you need 112 kg liquid R22 per hour and after expand 15 degree C and superheated to 20 degree C, need storage volume of vapour of 3.54 m^3 size per hour at pressure 6.7 Bar.

So for 16 Hour cooling without sun-power, you need 1792 kg R22 and 56.5 m^3 Vapour storage on 6.7 Bar pressure... if storage pump down completely to full vacuum in charging period...

ie solution is complete unrealistic in real world.

---

And R22 are already or going to banned in many country and more expensive in future to get ie manufactorys not interested make more R22 depend of several shrunken market

same way going for R407, R410, R404 etc. in future and already going to banned or very high taxed for new product in EU-contry...


is a lot better to cooling water with small refrigerant charge machine under sun time, you can store 11.6 Wh per litre Water and 10 degree K temperature change and give only need 428 Litre Water per hour for 5 kW cooling demand or for 16 hour 6.85 m^3 storage tank and same tank can used for cooled and heated water if you mange proper stratification in the tank., if you can afford 20K temperature difference (water cooled down to ~ 0 degree C with antifreeze agent) and accept lower COP on your cooling machine - you only need half tank volume around 3.5 m^3...