freon 410 problem in iraq

[rdholder]

An R-22 has a critical point temperature of 205.6 degrees F and loses about 6% of capacity for every 10 degrees above 95 degrees OSA.

An R-410A has a critical point temperature of 162.5 degrees F and loses about 7.5% of capacity for every 10 degrees above 95 degrees OSA.

Both refrigerants lose about 2% of capacity on a condenser for every 1000 feet of rise in altitude.

The performance of both R-22 and R-410A is influenced by condensing temperature – R410A is slightly more sensitive to condensing ambient temperature than is R-22 up to around 45°C. Above this temperature (equivalent to a condensing temperature of around 60°C) the refrigeration capacity of the R-410A system starts to fall off more rapidly. At this temperature the relative drop in capacity exhibited by R-410A systems is around 10% greater than that of an R-22 system.

RDHolder
shop.rdholder.com

[coolinman]

kefah

The reason your having problems with the new R-410A systems is due to the characteristics of the refrigerant and the outdoor temperatures your experiencing. R-410A is not designed for air cooled equipment at the temperatures you indicated.

If we go back to the principles of refrigeration, the way we cool is to send a liquid refrigerant to a heat exchanger where it boils. The only way to boil a liquid is to add energy to it, in our case HEAT. As we remove the energy surrounding the coil to boil the refrigerant we cool the area. This energy is now trapped in the refrigerant vapor and we need to release the heat energy to return the refrigerant to a liquid state to be used again to absorb more energy. And this goes on over and over. Pretty simple process.

In your case the problem is your outdoor temperature.

In order to condense a refrigerant vapor we compress it to increase its temperature above the ambient surrounding the heat exchanger coil. With the temperature of the refrigerant climbing above the ambient air (normally 15- 25 degrees “F”) the heat naturally flows out of the vapor and condenses the refrigerant.

I think in degree “F” so let’s convert. 60C = 140F, 70C = 158F. Using this information, a system operating in a outdoor condition of 60C will need to condense between 155F to 165F depending on the equipment (remember condense 15-25 degrees above ambient), in a outdoor condition of 70C will need to condense between 173F to 183F depending on the equipment (remember condense 15-25 degrees above ambient) This would be considered normal for the conditions.

The characteristics of R-410A are that it has what they call a Critical temperature of around 162F. This means that R-410A can’t exist as a liquid above this temperature no matter what the pressure is, as a matter of fact it will be a vapor no matter what the pressure needs to be. If you look back at the condensing temps at your temperatures at 60C you MIGHT condense if the condensing unit is designed for a minimum rise above ambient. At 70C it’s NOT going to condense.

The reason R-22 worked is the critical temperature is around 204F which would allow it be able to condense at the conditions above.

I hope this helps to explain why your having problems with an air cooled R-410A system in your location.

Good luck
Coolinman

[dlove]

An R-22 has a critical point temperature of 205.6 degrees F and loses about 6% of capacity for every 10 degrees above 95 degrees OSA.

An R-410A has a critical point temperature of 162.5 degrees F and loses about 7.5% of capacity for every 10 degrees above 95 degrees OSA.

Both refrigerants lose about 2% of capacity on a condenser for every 1000 feet of rise in altitude.

The performance of both R-22 and R-410A is influenced by condensing temperature – R410A is slightly more sensitive to condensing ambient temperature than is R-22 up to around 45°C. Above this temperature (equivalent to a condensing temperature of around 60°C) the refrigeration capacity of the R-410A system starts to fall off more rapidly. At this temperature the relative drop in capacity exhibited by R-410A systems is around 10% greater than that of an R-22 system.

RDHolder
shop.rdholder.com

Thank YOU, i have been telling this to people and they just don't understand this. Over and over i have said when you replace a R22 with a 410 you may need re-size it because swapping out a 3ton r22 with a 3ton 410 will not operate the same in high temps.

[AYservicetech]

Thank YOU, i have been telling this to people and they just don't understand this. Over and over i have said when you replace a R22 with a 410 you may need re-size it because swapping out a 3ton r22 with a 3ton 410 will not operate the same in high temps.

X2

Also.. With the iformation you have given, i believe a PROPERLY designed water cooled system best suits ur application

[mixsit]

And here's a quick low budget more harm than good in the long run fix.

http://www.gogreenitems.com/Cool_N_S...m_p/cnss-1.htm

The vid shows water being pulled into the coils. (No replaceable evaporation pads to protect the coil and throw-away when they foul collecting all the minerals.
Do they say what is in the water treatment canister?

[KB Cool]

The vid shows water being pulled into the coils. (No replaceable evaporation pads to protect the coil and throw-away when they foul collecting all the minerals.
Do they say what is in the water treatment canister?

Are you serious?

[mixsit]

Are you serious?

Nah.
I didn't think you were either.
Just a nod of caution for the possibly unsuspecting..
A close-up of the coil after a season or two would have been better.

[dlove]

Nah.
I didn't think you were either.
Just a nod of caution for the possibly unsuspecting..
A close-up of the coil after a season or two would have been better.

Interesting, yes i would be curious after a season how the coils look. in cold climates how much you want to bet it freezes, Because they forget its there...

[kefah]

Thank YOU, i have been telling this to people and they just don't understand this. Over and over i have said when you replace a R22 with a 410 you may need re-size it because swapping out a 3ton r22 with a 3ton 410 will not operate the same in high temps.

i didnt mean that i wnt to swap the 22 with 410a by changing the split unit freaon only
i meant changing the whole 22 split unit with new split working on 410a
when we tried the 410a new split their cooling was not so good since the temp is reached 55c in some places
also 22 freon cooling is very good but the conpressor is overheated then stopped working
so do you advice me to use freon 407c or not
thanx

[hvacvegas]

i didnt mean that i wnt to swap the 22 with 410a by changing the split unit freaon only
i meant changing the whole 22 split unit with new split working on 410a
when we tried the 410a new split their cooling was not so good since the temp is reached 55c in some places
also 22 freon cooling is very good but the conpressor is overheated then stopped working
so do you advice me to use freon 407c or not
thanx

Thats exactly what he said.

The system your trying to run is not designed to operate in the area you have it.
You need a different type of system.
Using ANY air source is not going to be effective.

[kefah]

thanx
ok

what is opinion if i use new split unit working on 407c
is freon 407c is best than r22

[greggerson88]

most air conditioning systems are designed for 90 degree ambient,for proper operation situations. clearly you are exceeding that, you have add extra tonnage for the added temperature discrepency.

[greggerson88]

basically just get a larger capacity condenser.

[beenthere]

thanx
ok

what is opinion if i use new split unit working on 407c
is freon 407c is best than r22

R407C is not better the R22.

[jbcrane]

Water cooled is the only solution. You could rig up a lawn sprinkler spraying on the outdoor coil as a test. Saw that one time on a call. Stacked coil completely blocked.

Sent from my DROID RAZR using Tapatalk 2

[timjimbob]

Water is more precious then R22 in the desert, isn't it?

[toocoolforschool]

Water is more precious then R22 in the desert, isn't it?

Excellent observation.

[dijit]

If this is a thermal power plant, they have to have water available in order to make steam to run the turbines. The best bet, like others have said is probably a water-source ac or heat pump and a cooling tower. An air-cooled ac could work but not at stock specs. You would need a higher compression ratio to get the difference between high and low side to be greater. If you can get a walk-in to freeze in Phoenix (where I live), with an air-cooled system, you can get a room to room temp in 60 C ambient. But it has to be designed to do so. And 60-70C ambient is at the maximum temp of condenser fans. Highest I have seen is 70C rated which, if that is really ambient, by the time the air pics up condenser heat, it will be much warmer and probably cause a very short fan life. I would go with a WSHP.

[timjimbob]

As posted earlier, different refrigerants have different "critical temperatures" that are less suitable to high temperatures. Any use of water to cool is complicated by minerals in the water. Typically, water in hot, arid climaytes is more problematic with fouling and if the hot climate is also very humid, there is little benefit to water cooling. Try to air cool, if all possible

[kefah]

thanks