Charging walk in coolers and freezers

[thethomas4]

Are you talking about just committing suicide and personally sucking that liquid refrigerant in or committing murder to the compressor by letting it suck straight liquid in? I'm guessing you mean metering in the liquid in to the suction line. Still, that can be time consumming.

What is the difference between sucking the liquid from a refrigerant bottle on the liquid line and a receiver from the liquid line they both go through a metering device and an evaporator prior to a compressor suction valve.

[tipsrfine]

What is the difference between sucking the liquid from a refrigerant bottle on the liquid line and a receiver from the liquid line they both go through a metering device and an evaporator prior to a compressor suction valve.

Didn't understand what you meant by "sucking". Usually "sucking" means hooking up to the "suction" line. A vacume can also "suck". The only other way to "suck" liquid refrigerant is by vaccume on the high side. So when you said "let it suck liquid from the liquid liquid line" I thought you meant just hook it to the suctin line and let it suck liquid straight to the compressor. If the unit's running, hooking the "refrigerant bottle" to the liquid line is not going to result in any sucking on the bottle.

[thethomas4]

Its late Saturday night I'm visiting with my buddy Weiser. Are messing with me?
A bottle of refrigerant open on a liquid line I don't think you will be in a vacuum if done right.

[tipsrfine]

Its late Saturday night I'm visiting with my buddy Weiser. Are messing with me?
A bottle of refrigerant open on a liquid line I don't think you will be in a vacuum if done right.

I'm drinking too so I'm thinking goodnight. Your post ain't makin any more sense to me than yours are to me.

[AtoZhvac]

http://sporlan.jandrewschoen.com/90-30-1.pdf

There is the link for charging with headmaster valves.

Raising the head pressure while charging is a waste of time, really. Yes, it will clear the sightglass, but it won't speed charging in any way.

Follow 90-30-1 and walk away.

Thanks for all of the help so far. I am majorly confused over the Sporlan info on charging. I have tried my best to understand how to apply the information and the table 2. I don't know if the design temp is the evaporator design temp or the anticipated outside ambient that is being referred to?

If anyone can make sense out of how it works please take this scenario and please tell me how to make sense out of the Sporlan data tables.

Here is the scenario:

Walk in freezer that has -20 cooling capability.
The system is charged with an outside ambient of 60 degrees and the sight glass has cleared and stabalized.Non unloading compressor.

Now say that I want to make sure that the charge for the headmaster is correct for the upcoming cold weather which could be as low as 20 degrees.

What data on table 2 do I use to determine the extra charge needed?

Thanks

[frigeguy]

As was stated earlier, close the king valve ( outlet of the receiver ) and charge liquid into the liquid line supplying the TX Valve. If that is not an option charge liquid in the suction line as far away from the compressor as possible ( usually at the evaporator coil ) I close the hand valve at the case and meter liquid in the suction slowly.

In the case of shutting the condensor fan off, I have only used this method to empty the system quickly into reclaim cylinder at low ambiant conditions, shut off bypass and cycle compressor building discharge pressure to force liquid out of receiver.

[Airmechanical]

As was stated earlier, close the king valve ( outlet of the receiver ) and charge liquid into the liquid line supplying the TX Valve. If that is not an option charge liquid in the suction line as far away from the compressor as possible ( usually at the evaporator coil ) I close the hand valve at the case and meter liquid in the suction slowly..

i have never used that method, i always dump in liquid (using discretion)

but your way sounds good as well



.

[timebuilder]

When initially charging ANY system, after drawing the vacuum down to the proper micron level, I charge as much as I can into the liquid line, until the flow out of the charging cylinder pretty much stops. Then, I start the compressor and begin metering refrigerant into the suction side.

I've never tried to close a valve between the compressor and the point where I am adding refrigerant into a liquid line. I would imagine you can't do this for long before the pressure in the receiver gets too high.

I'd like to hear more about it, though.

[jpsmith1cm]

Are you talking about just committing suicide and personally sucking that liquid refrigerant in or committing murder to the compressor by letting it suck straight liquid in? I'm guessing you mean metering in the liquid in to the suction line. Still, that can be time consumming.

Are you actually speaking from experience or are you parroting the BS that they spew out of texts and tech schools?

I have poured literally THOUSANDS of pounds of refrigerant into systems by charging liquid into the suction side.

[jpsmith1cm]

Thanks for all of the help so far. I am majorly confused over the Sporlan info on charging. I have tried my best to understand how to apply the information and the table 2. I don't know if the design temp is the evaporator design temp or the anticipated outside ambient that is being referred to?

If anyone can make sense out of how it works please take this scenario and please tell me how to make sense out of the Sporlan data tables.

Here is the scenario:

Walk in freezer that has -20 cooling capability.
The system is charged with an outside ambient of 60 degrees and the sight glass has cleared and stabalized.Non unloading compressor.

Now say that I want to make sure that the charge for the headmaster is correct for the upcoming cold weather which could be as low as 20 degrees.

What data on table 2 do I use to determine the extra charge needed?

Thanks

You need to give me more information.

Type of refrigerant.
Number and size of return bends on the condenser (remember to EXCLUDE any subcooling coils)
Length of the condenser tubes.
type of refrigerant.

Given that data and a few minutes and I wil give you the flooding charge.

[jpsmith1cm]

When initially charging ANY system, after drawing the vacuum down to the proper micron level, I charge as much as I can into the liquid line, until the flow out of the charging cylinder pretty much stops. Then, I start the compressor and begin metering refrigerant into the suction side.

I've never tried to close a valve between the compressor and the point where I am adding refrigerant into a liquid line. I would imagine you can't do this for long before the pressure in the receiver gets too high.

I'd like to hear more about it, though.

Unless you are massively overcharged, the pressure in the high side will level off, then actually drop a bit as the load on the compressor drops due to pump down.

[jpsmith1cm]

Thanks for all of the help so far. I am majorly confused over the Sporlan info on charging. I have tried my best to understand how to apply the information and the table 2. I don't know if the design temp is the evaporator design temp or the anticipated outside ambient that is being referred to?

If anyone can make sense out of how it works please take this scenario and please tell me how to make sense out of the Sporlan data tables.

Here is the scenario:

Walk in freezer that has -20 cooling capability.
The system is charged with an outside ambient of 60 degrees and the sight glass has cleared and stabalized.Non unloading compressor.

Now say that I want to make sure that the charge for the headmaster is correct for the upcoming cold weather which could be as low as 20 degrees.

What data on table 2 do I use to determine the extra charge needed?

Thanks

Table 2 tells you what percentage of the coil is to be flooded.

Now, with an ambient below 70, you need to be extra careful with this as it is fairly easy to overcharge. At an ambient of 60, it might not be too bad, but get down colder, and you can put an awful lot of gas into the unit.

At 60, you have already flooded part of the condenser, so you have to figure THAT amount out and also the total flooding charge out.

Soooo,

total flooding charge of say 8.5# (to flood from 70 degree ambient.)

At 60 degrees (use 60 as minimum ambient) your flooding charge is let's say 2#.

8.5# (total flooding charge) - 2# (amount ALREADY added) = 6.5# (amount left to add)

Clear as mud?

Good.

[tipsrfine]

Are you actually speaking from experience or are you parroting the BS that they spew out of texts and tech schools?

I have poured literally THOUSANDS of pounds of refrigerant into systems by charging liquid into the suction side.

Take a chill pill jpsmith, me and thethomas4 had a few drinks last night and it was pretty unprofessional. I know you have good experience and I respect and learn from your post. It's just the way thomas4 said "turn the bottle over and let it suck refrigerant" sounded funny so I poked some fun at him since we were both hanging out with our "buddy weiser".
On a more serious side, I have seen a very experienced refrigeration man "turn the bottle over" into the suction side and in a flash 10 lbs liquid straight to compressor. We were out in a week or 2 replacing the reed valves. He's getting old and I think he just screwed up due to his age.
And yes I am speaking from experience-albeit limited-and I understand the gap between theory and what real experience has to say about it.