# Refrigerant Charging Scale



## yuri (Nov 29, 2008)

No problema. As long as the resolution is okay. Might be a bit bulkier as it is meant for larger drums and a tech doesn't need a huge one for resi work.


----------



## hennyh (Nov 14, 2006)

I did it the other way around. I used a household package scale for a refrigerant scale. The cost was about $20 for a 55lb capacity digital scale vs. $100+ for a HVAC scale.

The HVAC scales are probably more rugged but I'm not a tech.


----------



## COLDIRON (Mar 15, 2009)

*Waste*

I think a scale for split systems is useless unless your using it for weight to charge a customer because of the different line sets and distances.

If you were doing package units or refrigeration work where the refrigerant amounts are very critical and are name plated I could see more of a use.

Of course you can always use it when rclaiming a system.


----------



## beenthere (Oct 11, 2008)

benjamincall said:


> Can you think of any reason why I shouldn't buy a refrigerant charging scale to use as both a shipping scale and a refrigerant scale? I don't see myself using it for more half a dozen mini split jobs, but a 110 lb. scale with .1 oz resolution would be valuable for a number of other applications.


Invaluable on mini splits. Especially on ones. Where someone else has been out and adding refrigerant, and has it over charged.

Also, helps you with billing if your a contractor.
And recovering refrigerant from systems you work on.
Plus, you don't have to wonder how full your recovering cylinder is. :no:


----------



## COLDIRON (Mar 15, 2009)

*REPLY TO benjamincall and beenthere*

1. Not worth it for the *amount of work* you are doing even on mini splits.
even if someone has tampered with the charge the weight is unknown.

2. I said Billing in my statement.

3. Stated reclaiming/recovering.

4. Use a bathroom scale as hennyh is for the amount of work.

5. If you can use the scale elsewhere and it's worth it for you go for it but I wouldn't buy one for working on 4 to 6 units especially with all the digital thermometers and technology to charge with superheat or sub-cooling.


----------



## beenthere (Oct 11, 2008)

The weight of the refrigerant in an overcharged unit is unknown.

But, the amount the unit is suppose to have, will be stamped on the data plate. Or in the install manual. Along with how much additional charge to add for the line set. Or remove if the line set is too short.
So it comes in very handy after recovering.

Hard to check subcool on a mini split. Dang liquid line ends inside the condenser.


----------



## COLDIRON (Mar 15, 2009)

*Not specific*



beenthere said:


> The weight of the refrigerant in an overcharged unit is unknown.
> 
> But, the amount the unit is suppose to have, will be stamped on the data plate. Or in the install manual. Along with how much additional charge to add for the line set. Or remove if the line set is too short.
> So it comes in very handy after recovering.
> ...


1. What I said

2. Impossible to charge by weight just a guess all the time unless line sets are precharged, different story.

2. recover/ reclaim what I said

3. Not specific as to sub-cooling or superheat general statement for:laughing: all HVAC people out there even though it was addressed to two people it's open forum.


----------



## beenthere (Oct 11, 2008)

SULTINI said:


> 2. Impossible to charge by weight just a guess all the time unless line sets are precharged, different story.
> 
> Factory pre charged line sets, are charged by weight.
> 
> ...


Since he's working on mini splits. Its important that he remembers that the line(small line) is not a liquid line that can be used to measure subcooling.


----------



## benjamincall (Apr 25, 2008)

Thanks for the input. I'm not going to spend more than $50 or so on the scale, so I think I'll proceed with the purchase. The applications for a good portable scale are endless: measuring out mortar mix, cooking, shipping, etc. I do have a recovery machine.


----------



## veesubotee (Nov 22, 2008)

*Question on 'weighing technique'*

When weighing refrigerant containers in the field, do you normally place the scale on top of the condenser (level, stable surface)?

If scale is placed on the ground, what effect do irregularities (slope, bumps, soft ground, etc.) have on accuracy of reading? Negligible?

V


----------



## beenthere (Oct 11, 2008)

Many condensers aren't big enough to set a scale on them. And not have it interfere with the condenser air flow. So if you set it on the condenser. You need to get the whole charge in wihtout the unit running. On those condensers.

If you can't set it on the condenser. Set it on as level an area as you can. And once you place your container on it, and zero it. You don't move it, or touch the cylinder.
Cause you won't always be able to get the same reading if you reposition it.

On an uneven surface, it will through the accuracy off. How much varies with how uneven the surface is.
So you can use a hard portable surface, that you can get reasonably level, and set the scale on it.


----------



## justplumducky (Aug 7, 2009)

SULTINI said:


> I think a scale for split systems is useless unless your using it for weight to charge a customer because of the different line sets and distances.
> 
> If you were doing package units or refrigeration work where the refrigerant amounts are very critical and are name plated I could see more of a use.
> 
> Of course you can always use it when rclaiming a system.


Why are refrigeration amounts for residential package units more critical as opposed to residential split systems?


----------



## beenthere (Oct 11, 2008)

Less copper piping, so less room to store excess.


----------



## yuri (Nov 29, 2008)

With mini splits the liquid line is the metering device so to work properly you have to weigh it in. 

With any other units you have some lee way and especially with a TX valve as it modulates. With a capillary tube in a refrigerator or mini split there is no TX valve so it has to be exact. With full blown refrigeration systems you have a receiver and sightglass.


----------

