Asked by: Amador Mapelli
home and garden indoor environmental quality

What does low high side pressure mean?

Last Updated: 10th March, 2020

Lower Low and High Side Pressures
Lower than normal pressures on both high and low side, with the correct amount of refrigerant, could mean a problem building pressure in the system or too much heat is being removed at the condenser. A pressure switch or sensor could be bad.

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Similarly, it is asked, what causes low high side pressure?

The needle valve may also get stuck partially open from grit or a sludging condition in the oil. This will cause high pressure to go directly into the compressor's crankcase causing high low-side pressures and low high-side pressures.

Also, 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.

Then, what causes high low side pressure and low high side pressure?

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.

What happens if refrigerant pressure is too low?

Low refrigerant means low pressure and low pressure means low temperatures that will eventually freeze something called an evaporator coil. When the evaporator coil freezes, cold liquid refrigerant flows through the refrigerant line, causing the surrounding moisture in the air to freeze.

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