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#### wetbar

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What is the lowest temp you can add freon?

Got a bet with a buddy!

#### Bigfoot

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What is the lowest temp you can add freon?

Got a bet with a buddy!
Depends on the freon and the pressure/temperature differential, either the atmospheric pressure or the pressure of the system you are trying to fill into. I guess you can add at anything above the boiling point of the freon you are using, filling into an empty system or into the atmosphere. As the pressure differential decreases (the pressure in the system increases), you are going to need more heat. You have to be able to build more pressure/temperature in the fill bottle, than the system you are trying to fill into.
The boiling point is usually very near the lowest possible temperature/pressure mark on your gage for that particular freon. I think it's around -40F for freon 12.
I can fill at most any temperature, my filling station has a heater or I sit the bottle in a bucket of hot water.
Maybe the correct answer would be anything above the freezing point of the freon (F-12 -158 F I think) you are using. Technically you could use gravity to feed freon as a liquid. if it was frozen you would have to use a spoon. LOL
Maybe the easiest answer would be to look at your low side gage, at the temperature equal to the low side pressure in your system and have your fill bottle above that temperature/pressure for that particular freon.

Clear as mud.

#### beenthere

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Depends on what equipment you have for charging systems.
Charging cylinders have heaters. So you can charge a system when your outside and its -80°F. :laughing:

Ok, thats not exactly what you were asking.

When working on heat pumps, its common to have to add gas when its 10°F outside.

Spme techs can't figure out how much gas to put in an A/C when its 50°F outside.

I work on systems that must run in cooling mode when its -10°F outside.
And I have to add gas to them sometimes. (they won't pay for the leak repair)

There is no minimum outdoor temp.

#### hvaclover

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Depends on what equipment you have for charging systems.
Charging cylinders have heaters. So you can charge a system when your outside and its -80°F. :laughing:

Ok, thats not exactly what you were asking.

When working on heat pumps, its common to have to add gas when its 10°F outside.

Spme techs can't figure out how much gas to put in an A/C when its 50°F outside.

I work on systems that must run in cooling mode when its -10°F outside.
And I have to add gas to them sometimes. (they won't pay for the leak repair)

There is no minimum outdoor temp.
been what about the mfg spec that say the min ODT is like in the 55 to65*
range. Sure I can charge an ac at 10*with my heated dial-a-charge, but I sue would not want to turn on the ac to check it.

Could you clarify what you me?

BTW this op has no bet with any one. He's a landlord fixing his own equipment.

OP, you don't have to be shady, we are a DIY site and will help anyone with a reasonable service request.

#### wetbar

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hvaclover - Thanks for the response, but I am not sure why I cant have a bet with someone. I bet you, you wrong! Is that a bet? Yes I am a land lord learning to work on my own units. . . and yes I just won a bet! well two bets since I just won one from you.

#### hvaclover

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hvaclover - Thanks for the response, but I am not sure why I cant have a bet with someone. I bet you, you wrong! Is that a bet? Yes I am a land lord learning to work on my own units. . . and yes I just won a bet! well two bets since I just won one from you.
go smart mouth somebody who gives a care.

Like you can prove the bet. You are obviously a not a skilled tech so if you had a bet going as you describe your buddy must be less skilled than you.

Right now with what you know of hvac you could be considered a threat to public safety the way you practice the trade.

#### wetbar

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. . . but you can prove I dont have a bet, right? Your right about what I know, and that is why I am on this web site getting help from the non dickheads. If you dont want to help then dont, but dont give the web site a bad name, cause you think you know someone 700 miles away. Its easy just cut your pc off and make this a better place!

#### hvaclover

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You're the one asking questions not me. I know what to do.

And I don't have to validate my self to a trigger tempered person like yourself. And I sure don't didn't give you justification to respond with hostility.

I'll still answer your questions though, part of my job is to ensure public safety thru the safe application of solid hvac practices.

#### beenthere

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been what about the mfg spec that say the min ODT is like in the 55 to65*
range. Sure I can charge an ac at 10*with my heated dial-a-charge, but I sue would not want to turn on the ac to check it.

Could you clarify what you me?
The manufacturer's min specs. Ar for min operating conditions.

As: The min conditions that the unit can be ran, for prolonged periods of time, with out the addition of low ambient devices/controls.
To prevent the indoor coil from freezing, and the compressor from receiving a liquid refrigerant flood back.

Those units not equipmed with a CCH of some type. Should be jogged before running it to check the charge.

Just to charge/check if additional charge is needed.
You can run a unit for 20 to 30 minutes and not freeze the coil. If you get the indoor temp up. Even if your 10 or 20° under manufacturer's listings.

Then there are several ways to simulate a 70 or 80° outdoor temp also.

#### hvaclover

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thanks for clearfying

#### pnutzhome

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go smart mouth somebody who gives a care.

Like you can prove the bet. You are obviously a not a skilled tech so if you had a bet going as you describe your buddy must be less skilled than you.

Right now with what you know of hvac you could be considered a threat to public safety the way you practice the trade.

not slow just stupid

#### hvaclover

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