Tip & How-To about Heating & Cooling

Charging AC by superheat and subcool

First charging a unit by superheat, **this is only for Acs with an orifice or capillary tube**.

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling, **this is for Acs with a thermostatic expansion valve, it’s common to see a sight glass on the liquid line (on these units with a sight glass just clear it, when, indoor room is at approximate set point of the thermostat). If there is no sight glass then the Optimum sub cooling is 12° to 15° at the outdoor unit.**Hook up your gages and put a thermometer on liquid line (small line), start the AC. Measure the temperature of the liquid line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant,(you can also use a temperature pressure chart), now read the thermometer, let’s say the liquid temperature( the thermometer) is 100° and the saturation temperature (the gages or temp. press. Chart), is 114°, subtract the liquid temperature from the saturation temperature, 114°- 100° = 14° subcool.

This is also the only way to know if your a/c has the proper charge.

Hello, if this is a R-22 unit your low side should between 70-75 psig and high side should be between 225-230psig. But keep in mind always measure the superheat if it is a fixed orifice and subcooling if it is a txv unit

Jun 07, 2011 | Amana Heating & Cooling

Charging AC by superheat and subcool

First charging a unit by superheat,**this is only for Acs with an orifice or capillary tube**.

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,**this is for Acs with a thermostatic expansion valve, it’s common to see a sight glass on the liquid line (on these units with a sight glass just clear it, when, indoor room is at approximate set point of the thermostat). Optimum sub cooling is 12° to 15° at the outdoor unit.**

Hook up your gages and put a thermometer on liquid line (small line), start the AC. Measure the temperature of the liquid line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant,(you can also use a temperature pressure chart), now read the thermometer, let’s say the liquid temperature( the thermometer) is 100° and the saturation temperature (the gages or temp. press. Chart), is 114°, subtract the liquid temperature from the saturation temperature, 114°- 100° = 14° subcool.

First charging a unit by superheat,

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,

Aug 09, 2010 | Amana Heating & Cooling

Charging AC by superheat and subcool

First charging a unit by superheat,**this is only for Acs with an orifice or capillary tube**.

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,**this is for Acs with a thermostatic expansion valve, it’s common to see a sight glass on the liquid line (on these units with a sight glass just clear it, when, indoor room is at approximate set point of the thermostat). Optimum sub cooling is 12° to 15° at the outdoor unit.**

Hook up your gages and put a thermometer on liquid line (small line), start the AC. Measure the temperature of the liquid line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant,(you can also use a temperature pressure chart), now read the thermometer, let’s say the liquid temperature( the thermometer) is 100° and the saturation temperature (the gages or temp. press. Chart), is 114°, subtract the liquid temperature from the saturation temperature, 114°- 100° = 14° subcool.

First charging a unit by superheat,

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,

Mar 19, 2010 | Panasonic CW-1006FU Air Conditioner

It depends on the indoor and outdoor temperature and humidity. The low side pressure can be in the area of 135# to 145# with an indoor temperature of 80° and 50% relative humidity, and the outdoor pressure can be in the area of 300# to 330# on a 95° day depending on effeciency rating.

If your asking this to charge your a/c this is not how to charge your a/c.

Charging AC by superheat and subcool

First charging a unit by superheat,**this is only for Acs with an orifice or capillary tube**.

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,**this is for Acs with a thermostatic expansion valve, it’s common to see a sight glass on the liquid line (on these units with a sight glass just clear it, when, indoor room is at approximate set point of the thermostat). Optimum sub cooling is 12° to 15° at the outdoor unit.**

Hook up your gages and put a thermometer on liquid line (small line), start the AC. Measure the temperature of the liquid line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant,(you can also use a temperature pressure chart), now read the thermometer, let’s say the liquid temperature( the thermometer) is 100° and the saturation temperature (the gages or temp. press. Chart), is 114°, subtract the liquid temperature from the saturation temperature, 114°- 100° = 14° subcool.

If your asking this to charge your a/c this is not how to charge your a/c.

Charging AC by superheat and subcool

First charging a unit by superheat,

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,

Dec 25, 2009 | Heating & Cooling

You are still low on freon.
Charging AC by superheat and subcool

First charging a unit by superheat,**this is only for Acs with an orifice or capillary tube**.

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,**this is for Acs with a thermostatic expansion valve, it’s common to see a sight glass on the liquid line (on these units with a sight glass just clear it, when, indoor room is at approximate set point of the thermostat). Optimum sub cooling is 12° to 15° at the outdoor unit.**

Hook up your gages and put a thermometer on liquid line (small line), start the AC. Measure the temperature of the liquid line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant,(you can also use a temperature pressure chart), now read the thermometer, let’s say the liquid temperature( the thermometer) is 100° and the saturation temperature (the gages or temp. press. Chart), is 114°, subtract the liquid temperature from the saturation temperature, 114°- 100° = 14° subcool.

First charging a unit by superheat,

Optimum superheat is 12° to 15° at the compressor or suction line outside the unit.

Hook up your gages and put a thermometer on suction line (large line), start the AC. Measure the temperature of the suction line and read the pressure on your gages. Theres a temperature scale on your gages for R-22 or R-410A the needle will show you the pressure on the outer scale and if you follow it down to the R-22 or R-410a inner scale that is the saturation temperature for that refrigerant, (you can also use a temperature pressure chart), now read the thermometer, let’s say the suction temperature( the thermometer) is 67° and the saturation temperature (the gages or temp. press. Chart), is 55°, subtract the saturation temperature from the suction temperature, 67°- 55° = 12° superheat.

Charging by Subcooling,

Oct 05, 2009 | Heating & Cooling

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