What should the high and low side pressures be for r22?

Asked By: Jefferey Elberskirchen | Last Updated: 3rd June, 2020
Category: home and garden indoor environmental quality
4.3/5 (20,562 Views . 10 Votes)
High side reads about 250 give or take at 90 degrees ambient temperature. Low side reads 43. Using farthest outside scale on gauge. generally it should be around 225 on the high side and near 70 on the low.

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Keeping this in consideration, what should my Pressures be for r22?

Example R-22 Refrigerant Temperature vs Pressure Data
Ambient Temperature in °F1 R22 Vapor Pressure at Sea Level R-22 Low Side Pressure2
95°F (35°C) 181.9 psig 68 psi
110°F (43.3°C) 226.4 psig
150°F (65.6°C) 381.7 psig

Additionally, what is the suction and discharge pressure for r22? For example, a high-efficiency condensing unit using R-22 typically operates with a suction pressure of about 68 psi and a discharge pressure of about 250 psi at an outdoor temperature of 95°F.

Herein, what should the high and low side pressures be?

The low-side should be near 30 PSI at 90 degrees Fahrenheit or less. Pressure that is too much lower or higher shows there is a problem. On a properly working system, high-side pressure will be about twice the ambient temperature, plus 50 PSI.

What is a good superheat for r22?

approximately 10F

39 Related Question Answers Found

What is the condensing temperature of r22?

The influence of the evaporator temperature on the volumetric refrigerating capacity (VRC) at the condensing temperature of 50 o C for R22 and the two alternative refrigerants is shown in Fig.

What is the best replacement for r22 refrigerant?

The best replacement for R-22 Freon is usually R-407c. It has a very low loss in capacity (0 – 5%) relative to R-22 and is less expensive than many other R-22 replacement refrigerants. If a system has R22 in it already you cannot use a replacement refrigerant to simply add to the R22.

What happens if you mix r22 and r410?

No, you cannot. To make a short story long, R410A and R22 are refrigerants. They are both good refrigerants and they both work, but they have to be charged in the system at different pressures.

How cold is liquid r22?


R22 is the short name for the halocarbon compound CHClF2 (monochlorodifluoromethane), which is used as the refrigerant. R stands for the refrigerant. In the number “22” second “2” denotes the number of the fluorine atoms in the compound. The boiling point of R22 is -40.8 degree Celsius (-41.4 degree F).

What is the suction pressure of r22?

Pressure Variables
For example, in a refrigeration unit, the refrigerant R-22 should operate at 75 psi on the suction side.

What should the gauges read on 134a?

For a low pressure gauge, a reading of 25 pounds per square inch (psi)to 40 psi is optimum. On the other hand, a high pressure gauge should read between 225 psi and 250 psi.

What should the high and low side pressure be in a r134a system?

R134a Pressure Gauge Chart
Ambient Temperature (°F) Low Side High Side
80° 45-50 psi 175-220 psi
75° 40-45 psi 150-175 psi
70° 35-40 psi 140-165 psi
65° 25-35 psi 135-155 psi

What should my AC gauges be reading?

IMPORTANT - UNDERSTAND WHAT NORMAL GAUGE READINGS ARE.
AIR TEMP (C) RED GAUGE (PSI) BLUE GAUGE (PSI)
10 50-100 20-30
20 100-150 20-30
30 150-200 25-35
40 180-225 25-35

Why is my low pressure side high?


The high low side readings (with normal high side readings) are a result of thermostat switch malfunction. The thermostat might have the wrong range of temperature. To get normal readings, you would need to get the thermostat switch replaced by a local mechanic.

Do you charge AC on high or low side?

The high side port should be on the line between the condenser and the expansion valve or orifice tube while the low side port will be on the return line between the evaporator (firewall) and compressor. The high side port is larger in size than the low side.

Why is my low side AC pressure low?

An overcharged AC system in your car can also cause your pressure readings to be off on the low side. This is a situation that will also need to be corrected. To do this, you will need to remove refrigerant from the AC system. Ideally the reading should be at 30 psi for the low side pressure.

What should AC pressure be with engine off?

That's normal with the compressor off. Then watch the pressures when you turn it on. The low side will drop to 25-40psi, and high side should go to around 150-200psi.

Can you use r134a gauges on r22?

R134A is typically used in automotive/small appliance applications. Assuming you are talking about a "room air conditioner", the correct up to date refrigerant is R410a. You can use any gauges you like to check the pressure of the system, with slight risk of cross contamination.

What causes a compressor to ice up?

A freeze up can also be caused by low refrigerant and improper fan operation. Faulty thermostats and drainage problems are often causes of a freeze up. In the cooling process, an AC unit condenses water vapor into liquid that drains outside. If the coils are frozen, the ice will cause a blockage for the drain hole.

How do you use AC manifold gauges?

How to Use A/C Manifold Gauges
  1. Connect the low side hose (blue) to the low side port on the A/C unit.
  2. Connect the high side hose (red) to the high side port on the A/C unit.
  3. Open both valves so that the gauges register the A/C system pressure.