I have 2002 Honda cr-v. For A/C 1. Why a/c clutch engaging and disengaging on my cr-v? 2. Do I need to change high pressure valve?

I have 2002 Honda cr-v. My car A/C is not working good. A/C clutch engaging and disengaging problem. When a/c clutch engage that time Freon pressure is 30 PSI at Low side and when a/c clutch disengage at that time Freon pressure is 100 psi at Low side. On compressor has high pressure relief valve. Sometime high pressure relief valve open and Freon is coming from high pressure valve. I have HS-110R Keihin compressor on my cr-v. High pressure valve p/n: 38801-PCA-006 ( Valve sub. Assembly… From Honda dealer )
My questions:
1. Why a/c clutch engaging and disengaging on my cr-v?
2. Do I need to change high pressure valve?

It's normal for the actual A/C compressor to go on & off. That keeps the condenser in front of the radiator from icing-up. Some cars have a MAX A/C setting where the compressor works continually, but that should only be used in the desert with it's LOW humidity levels.

Your orifice tube is clogged up. For you to have that much pressure in the low side it has to be blocked. That is the reason you flush the A/C system after the compressor blows up.

Your system is overcharged for refrigerant to escape the pressure relief valve.
It's not the orifice tube or TXV.
Have all the refrigerant evacuated/recovered, then add refrigerant by WEIGHT only. There's a sticker under the hood indicating how much is needed. Gauges are used to check the compressor function and not even close in measuring refrigerant levels, especially when using R-134a.

If the AC is blowing cold air and keeping the set temperature setting, there's nothing wrong with the AC system. If it is not, turn off the engine and wait overnight. Get static pressures (engine off) for both low side and high side. Pressures should be about the same and should have values equivalent to ambient temperature (in F). If the pressure is low, evacuate the system (you can get a mechanic to do this), check if the vacuum holds for 15 minutes and run the vacuum pump again for about 45 minutes. Put a fresh charge using a scale and check the system again.

When the 134a charge is low from slow leaks the compressor will cycle like that. Buy a can of 134a with the sealer in it and charge the system until you get 40 degree air out of the center vents.

Engaging and disengaging is normal. If air is not real cold, could be low on Freon.

A/C normally does that, but if it's more than usual, it could be low on refrigerant or if you just had it recharged, it could be too much in the system.

1. If you say the high side has blown off. Then you either have a fan that is not running, the fan behind the radiator MUST be running at ALL times. 2. The old compressor is breaking down and bits have gotten in the orifice tube and are plugging it up.
2. It was overcharged.
3. A LOW system will NOT blow off the high pressure side.

Are you getting air through your condenser? You might need to check condenser for cleanliness or as previously noted your condenser fan(s) may not be running.

Name is Jeff