R22 normal operating pressure

With 95 F outdoor temperature and 80 F indoor temperature you can expect a 125 F condensing temperature, (ambient plus 30).
95 F + 30 F = 125 F
Convert temperature to pressure, R 22 at 125 F = 279 psi
Indoor temperature (80 F) minus 40 F = 40 F evaporating temperature.
Convert temperature to pressure, R 22 at 40 F = 70 psi.

So, what this means is that the normal operating pressure depends on the indoor and outdoor temperature.

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