split system charging

[frankman]

after installing a split system more refrigerant is needed based on the length of the line set. the amount of extra ***** needed to add is based on liquid line size right? does it matter what the suction line size is? for instance the manufacturer states that the condensing unit is charged with 180 oz of refrigerant for up to 15 feet of line set, but if you have a 45 foot line set you have to add ***** for 30 more feet of line set. the liquid line size is 3/8 size and the suction lin size is 3/4 on the system im referring to.

[paul_h]

Are you using the same size tubing that the unit is designed for?
Is the total length (between the indoor and outdoor, not liquid line length added to suction line length) under the permissable total length stated by the manufacturer?

If same pipe diameter, if not over the maximum range, the extra charge required as stated by the manufacturer is for the extra difference in distance between the indoor and outdoor units. They already assume suction and liquid lines to be the same length and have factored that into their extra charge required.

So if you are using the same size piping, then you add ***** for 30 more feet.

[monkey spanners]

Is this a mini split or an American style system to a central ducted air handler?

Mini split like we get over here and its grams per meter over the pre charged lenght, central air and it can be off a chart, or done with subcooling or superheat depending on the expansion device.

[nike123]

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[nike123]

after installing a split system more refrigerant is needed based on the length of the line set. the amount of extra ***** needed to add is based on liquid line size right? does it matter what the suction line size is?

No, it does not much.
Volume of evaporated refrigerant is many times higher than volume of liquid refrigerant.
For example 1 kg liquid R410 at 4°C bulb point is 0,86 l volume and 10K superheated vapor is 32,3 l.

[frankman]

i know you add ***** for 30 more feet but how do you know how many ounces to add for the 30 feet.

[frankman]

this is american style split system heat pump r22 3 ton.

[nike123]

this is american style split system heat pump r22 3 ton.

Then you charge by superheat table or weight stated in instalation manual.

[ClimateControl]

Correct, the install manual will tell you how many grams per Meter or foot. There are tons of video's out there to help you.