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View Full Version : Are these true? or they just exaggerating it? - R22 replacement



ahmadshafiq87
16-03-2011, 08:45 AM
Hi all.

Please take a look at these. Is it true as it claim to be? HC-22a is a drop in replacement for r-22. my company is considering to use it.

6488

how exactly will the change of refrigerant will lower the energy consumption?

Brian_UK
16-03-2011, 10:41 PM
It shows three different reductions, why is this?

ahmadshafiq87
17-03-2011, 06:55 AM
It shows three different reductions, why is this?

I also didn't understand their purpose of doing that. I've call one of their customers, and unfortunately, the company that have been using the refrigerant (HC-22a)has converted back to use R-22. Have to make another call to another customer of them. anyone have any experience using hydrocarbon replacement for R-22?

paul_h
17-03-2011, 08:49 AM
I'm starting to hear of hydrocarbon refrigerants to replacing R22, though I've never seen it or used it. Have a look at hychill in australia.
http://hychill.com.au/
http://hychill.com.au/pdf/whcse.pdf

ahmadshafiq87
17-03-2011, 10:13 AM
erm.. quite interesting facts you got there. anyhow, R-417 are getting little popular as a drop in replacement for r-22. what your say?

paul_h
17-03-2011, 11:33 AM
What's my say?
R417 is the drop in replacement for R22.
I don't care at the moment because I can still buy R22 though, so I've given it no thought.
the PDF I linked though is interesting. It's fact that major fridge manufacturers have switched to r600a to be more efficient, but then again, r134a wouldn't be hard to beat in any aspect.

stufus
17-03-2011, 11:50 AM
That's a strange one .
How do they go about selling that to a customer?
We can offer you a power consumption reduction of 20% and possibly +or- a further 5%.But we don't know !
Fair enough, A reduction is a Reduction ,but people like fact's.
It's interesting must look into it.
Cheers
Stu

ahmadshafiq87
18-03-2011, 02:15 AM
paul_h and stufus,

thanks for your help. I must say that the proposal is quite confusing.

I don't care at the moment because I can still buy R22 though, so I've given it no thought.

i think i would propose that. why such a rush, when the thing is still there, and the others are still in grey?

Fair enough, A reduction is a Reduction ,but people like fact's.

yeah, as long as the industry using conscious people to run the show.

allnatural
20-03-2011, 12:15 AM
Hi,

I'm a technical advisor for HyChill - a major supplier of hydrocarbon refrigerants.

Using the correct blend of hydrocarbon refrigerant in place of R-22 will, on the overwhelming majority of cases, produce higher EER (Energy Efficiency Ratio) outcomes compared to R-22.

In HyChill's case, the product which can be used to replace R-22 is called "Minus 50". The name refers (approximately) to the boiling point of this particular blend of propane and ethane, which is around -50 degrees Celsius.

Some of you have been discussing the statement that energy savings for R-22 conversions to HC can produce a wide range of energy savings - anywhere from 5% to 20%.

I hope to explain why the savings can vary so much.

Basically, it comes down to the fact that the R-22 systems were designed to work on R-22 and due to the fact that the hydrocarbon refrigerant has different physical and thermodynamic properties, the full cooling potential of the hydrocarbons are not fully utilized. The extent of utilization varies depending on the particular design nuances of the particular model of system.

Some of the physical differences of Minus 50 compared to R-22 that are related to this issue include:


The different vapour density profile of hydrocarbons, and
The slightly lower "high side" pressures when using hydrocarbons



The former is relevant to optimum compressor design. The latter is relevant to pressure switch set points. All these factors (and more) affect, to varying degrees, the extent to which the cooling capability of the hydrocarbons is fully utilized.

I hope I've explained that well enough.

Yes, fluorochemical R-417 is the "official" replacement for R-22. You can bet your left leg it won't perform as well as R-22. Just like the supposedly "new" fluorochemical R-1234yf, R-417 is anything but "new". These refrigerants have been around for a long time (or the constituents thereof). Just like R-134 (vs R-12), the reason these "replacements" were never promoted until environmental concerns forced the manufacturers hands was because they are poorer performers than the original fluids, basically without exception.

R-1234yf, the new (and highly toxic) replacement for R-134a (which was a replacement for R12... hang on, I think I see a pattern here) performs even worse than R-134a (and thats saying something). Just check out the critical temperature of R-1234yf - it is much lower than R-134a and will ultimately result in a lot of end-user dissatisfaction in the really hot climates in this world as it will simply fail to function. But (at the moment at least) they are having it forced down their throat - unless, of course, they break free of the monopoly and use hydrocarbons, as many workshops have been doing for around 20 years now.

All the best,

John W Clark
Technical Advisor
HyChill

allnatural
20-03-2011, 12:22 AM
All,

One more thing: do remember that all refrigerants are dangerous and potentially lethal, and different refrigerants require different safety considerations. Hydrocarbons are more flammable than most fluorocarbons, but less toxic. In some cases a simple drop-in replacement with HC's is reasonable, but in some cases modifications will be required to accomodate safety and performance differences. A careful and realistic assessment of your own skills, experience and training handling and using different refrigerants is a MUST. The last thing HyChill wants, both for your own wellbeing, that of your customers and of the natural refrigerants industry, is for careless work to cause fires that will become another propaganda piece for the f-gas cartel.

All the best,

John W Clark
Technical Advisor
HyChill Australia

ahmadshafiq87
21-03-2011, 05:29 AM
Hi John.
Thanks for your advice.
That explanation do give me clear understanding on the proposals. I'm quoting your reply here to be as one of my references. Thanks a lot!

Shafiq
Process Engineer
Barry-Callebaut Malaysia Sdn Bhd.

mbc
21-03-2011, 09:05 AM
safety is very important and it is mean thing we have to think in first step.

xxargs
02-04-2011, 05:56 PM
I agree HFO1234yf is not so good alternative in MAC application. it's flammable, but oil and fuel as gasoline burns also very hot if ignite in accident situation. but worse thing, HFO1234yf burns with highly toxic fumes compare to fumes from burning HC as propan/isobutan/gasoline

i make some calculation on theory cooling COP with +2/70 degree C setup without super heating or supercooling and compressor with 1.0 in isentrop efficiency

this give for R134a:

cooling COP: 2.3
suction volume : 2.63 m^3 per kWh
mass flow:

xxargs
02-04-2011, 07:20 PM
(seems not editing function here)


OK again...


I agree HFO1234yf is not so good alternative in MAC application. it's flammable, but oil and fuel as gasoline burns also very hot if ignite in accident situation. But worse thing, HFO1234yf burns with highly toxic fumes compare to fumes from burning HC as propan/isobutan/gasoline.

I make some calculation on refprop theory cooling COP with +2/+70 degree C setup without super heating or supercooling and compressor with 1.0 in isentrop efficiency

this give for R134a:

cooling COP: 2.42
suction volume: 2.44 m^3 / kWh
mass flow:37.7 kg/kWh
volume flow liquid side:37.8 liter / kWh

HFO1234yf

cooling COP: 1.97
suction volume: 3.1 m^3/kWh
mass flow: 59.1 kg/kWh
volume flow liquid side: 70 liter/kWh


for 60/40 mass percent propane/isobutane:

cooling COP: 2.3
suction volume: 2.6 m^3/kWh
mass flow: 19.4 kg/kWh
volume flow liquid side: 44 liter/kWh

and surprise! - DME (DiMethylEther)

cooling COP: 2.86
suction volume: 2.2 m^3/kWh
mass flow: 13.9 kg/kWh
volume flow liquid side: 24 liter/kWh

all of them has pressure range fit for typical R134a-cooling cycle.

DME seems very good refrigerants for R12/R134a replace if possible to handle flamable risk simular for propan/isobutan/gasoline etc.

typical car AC have practical cooling COP from 0.99 to near 2.5 with R134a as best in temperature setup as +8/+25 degree air temperature, data take from Sanden-report HFO1234yf and R134a comparison, so is many other thing above type of refrigerants make car AC so inefficient compare to other cooling machine.

But is very clear R134a using HFO1234yf as drop in on unmodified car AC lose very much cooling capacity depend of HFO1234yf bad cooling capacity and need around 50% more mass flowing around system for same cooling capacity as R134a...

HFO1234yf need suction gas heat exchanger with liquid line to make better cooling COP and also protect compressor from liquidizing of HFO1234yf in compression stage...

research
02-04-2011, 09:11 PM
Just be sure to check your local codes for suitability of the replacement refrigerants.
Example; both propane R290 and ethane R170 are A3 refrigerants.

North American codes prohibit using A3 refrigerants for most occupancies, and have stringent regulations for using them in allowed occupancies.

Always make sure you are aware of the codes, penalties and liabilities before changing refrigerants.