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ZeroTolerance
09-05-2010, 07:44 PM
I've read so much different BS on how to charge a liquid (404a) into a system its ridiculous and now I'm starting to get confused. I really wish if people didn't know wtf they were talking about they wouldn't input or give advice on the procedure.

So, I typically input the 404a as a liquid on the high pressure side at the king valve coming out of the receiver WITH the system running. Is this the correct method?

I hear people say leave the system running, shut it off, throttle the 404 in the low pressure vapor side as a liquid, etc.

What is the real procedure and BEST procedure when charging in a liquid state?

And when would you ever want to charge the 404A on the low pressure side if ever?

cool runings
09-05-2010, 07:57 PM
So, I typically input the 404a as a liquid on the high pressure side at the king valve coming out of the receiver WITH the system running. Is this the correct method?

I hear people say leave the system running, shut it off, throttle the 404 in the low pressure vapor side as a liquid, etc.

What is the real procedure and BEST procedure when charging in a liquid state?

And when would you ever want to charge the 404A on the low pressure side if ever?


What you are doing is fine, but it is only one of the ways to do it.

It is not BS realy it is common sense.

Put the refrigerant in the system anyway you want just do it in liquid form. (you could even do it in vapour form as long as you charge the whole cylinder)

If that means weighing the whole charge into a reciever or into the liquid line with the reciever valve closed when running or throtled into the suction while running or even from an access point in the suction near the evaporator.

It does not matter. It honestly doesn't

What does matter is that you are comfortable doing it the way you do.

coolrunnings

.

ZeroTolerance
09-05-2010, 08:13 PM
I heard though that when charging via liquid on the suction side it could and would damage the compressor? As liquids don't compress and BOOM there goes your compressor.

So is the proper procedure to throttle it in while the system is running or while its off if doing it near the compressor on the suction side?

monkey spanners
09-05-2010, 08:13 PM
I would charge enough liquid to run the system into the reciever with the system off, then run it up and charge into the suction valve on the compressor, i would throttle the valve on the gauge manifold so that little or no liquid reached the suction valve on the compressor. Effectivly turning the gauges into a hand expansion valve.

If you are not charging the whole bottle, so long as the refrigerant leaves the bottle as a liquid, it doesn't matter if it vapourises before reaching the system.

And as Cool runnings says if you are putting the whole bottle into the one system you can charge as a vapour.

Jon

sneep
09-05-2010, 08:18 PM
What you are doing is fine, but it is only one of the ways to do it.

It is not BS realy it is common sense.

Put the refrigerant in the system anyway you want just do it in liquid form. (you could even do it in vapour form as long as you charge the whole cylinder)

If that means weighing the whole charge into a reciever or into the liquid line with the reciever valve closed when running or throtled into the suction while running or even from an access point in the suction near the evaporator.

It does not matter. It honestly doesn't

What does matter is that you are comfortable doing it the way you do.

coolrunnings

.

High side charging with the system running is not how you do it. You could pump your can full and explode it.

Dumping liquid into to high side is a normal practice with the system off. As is metering liquid into the low side when it's running.
What matters is safety.

ZeroTolerance
09-05-2010, 08:21 PM
"or into the liquid line with the reciever valve closed when running"

Are you referring to putting the charging line on the output (king valve) of the receiver and shutting off the input (king valve) of the receiver and charge it while the system is running?

monkey spanners
09-05-2010, 10:06 PM
If you shut the input valve on the reciever you will just fill your condenser up with liquid and the unit will either, trip on the high pressure switch if fitted, the compressor will stall and trip a breaker, or there will be a loud bang. If there is a loud bang, don't worry, you won't hear it...

Why not get yourself one of thoses charging metering devices which you fit on the bottle and it boils the liquid off as it goes through?

ZeroTolerance
09-05-2010, 10:22 PM
Thanks for all the info; I am new to the game so please bare with me. I don't have a mentor/teacher to learn from, so I have been doing a lot of research on my own (online). I am a facilities manager and like to be hands on, so I try and do all the work the restaurants request myself without having to outsource.

surenuff
11-05-2010, 06:04 AM
If it is a system that holds a lot of refrigerant, and it is empty, then you should be in a vaccuum. So charging into the liquid line until the pressure equalize should not be a problem. Once the pressure equalizes, then start the unit and start metering in liquid into the low side.(meter it with your manifold and hoses). If the unit is very small, you can overcharge it before it even equalizes.

Brian_UK
11-05-2010, 05:10 PM
You can also use a quick-charger like this one... (It seems somewhat expensive so please look around)

http://www.professionalequipment.com/imperial-refrigerant-charger-kwik-charge-535-c/hvac-accessories/

B G Scott
12-05-2010, 11:14 AM
You can also use a quick-charger like this one... (It seems somewhat expensive so please look around)

http://www.professionalequipment.com/imperial-refrigerant-charger-kwik-charge-535-c/hvac-accessories/
Been using the quick charge for many years, well worth the money, save you a lot of time and you don't have the risk of liquid slugging the compressor.

cadillackid
13-05-2010, 09:48 AM
im going to have to get me one of those.. ive always just used a sight glass in the gauges and made sure i was evaporating in my manifold.. but is a pain as the pressure on the system changes...
-Christopher