High head pressure, normal suction pressure? what r some things i can check for?

Most 410-a Units will work at a vapor pressure of 125-140 suction, the normal head pressures range from 300-425, First thing i would do is get a water hose and make sure the condenser coils are clean, which affects your head pressure. Also make sure the condenser fan motor is spinning at a speed that seems normal and that your feeling good heat come out of it. And of course the normal clean filter check and make sure your evaporator coils are clean as well.
Hope this helps.
Michael

I’m happy to help further over the phone at https://www.6ya.com/expert/michael_341f3f9dee622e54

Your head pressure is a little high, depending on the ambient temp and your suction pressure is a little low. The suction pressure should be around 68 psig, the equivalent of a 40 degree coil. You can try adding a little refrigerant, check your compressor amp draw. If head pressure keeps going up and suction doesn't come up you may have a restricted metering device or filter dryer

lower fan speed.....and double check head pressure, sounds very low!!! should be around 250-275.....also make sure the return air grill is large enough.

Hi, sounds as though for this to be its 2nd compressor for such a newer unit, the superheat was not right when the compressor was installed. I don't know what freon you are using the new R-410A or the regular R-22. There's a big difference in pressure, but now I see your pressure reading and its R-22 for these readings.For a 2 ton unit, you would use the superheat charging method for a unit that doesn't use a thermostatic expansion valve ( T X V ) and not the sub-cooling. A 23 degree super heat at that outdoor ambient temperature is way to high for that unit, you will loose the compressor again!!. Super heat killed the compressor is the saying and that's a fact. Suction pressure should pull down just as quick as the head pressure unless the valves are going and weak, or you have a scroll compressor that has a valve plate that is going, or you are low on charge. With a ambient of 95*, you should be at around 270p.s.i. on your head pressure as 210 to 200 is way low. Suction line temp should be around 68 to 70, with a suction line temperature of 50 to 51 degrees, which would give you a 10 to 12 degree F super heat. I don't know when the second compressor was installed, but it has to be low on charge to be such a low head, and high super heat and you will loose this compressor again, its only a matter of time before you have a burnout. It was either under charged when installed, or has a very small leak at one of the joints. I hope the liquid line drier was replaced also. It shows me you have some knowledge on a/c operation, so you need to get that superheat down to between 8 and 10 degrees for this unit to cool properly, and leak check it also. Did you buy a extended compressor warranty? Lets get the head pressure up and superheat down and you should be OK unless the valves or valve plate is weak. Once you loose the valves, you will have a lower than normal head pressure and a high suction pressure. Compressor just won't pull down anymore. I hope I have been of help to you and ask of you to be kind when rating me. I will be here for you if and when you need me for anything.
Sincerely,
Shastalaker7
A/C & Heating Contractor

90 psi is very high for R22....low for R410 refrigerant. If leaking by the head pressure and suction pressure will be close to to the same reading

Hi, High head and a low suction pressure can indicate a couple of different things. One, condenser coil very dirty and needs to be washed very well. This will bring your head pressure down but let it run back up to normal engine temperatures. If the head is ok after you clean it, and suction is even lower, you may still be low on charge. If the system is over charged will cause this problem. You may want to clean coil, evacuate unit, and weight in your charge. Charge is critical on a auto a/c. You may also have a restriction in the filter drier or site glass. Go through the basics first. Suction should run about 18 p.s.i. Head will run about 27*F over ambient.If you are running R-12 or 134-A, the pressures will be close on your gauges. Go by your scale on the inner part of your gauge which is temperature. So, for R-12 with an outdoor temp of 90 degrees, your head will be about 150 p. s. i. Remember, the charge is critical. Good luck,
Shastalaker7

Hey there. First question I have is if you have a heat pump or straight ac. Straight ac is easy to diagnose. Your suction pressure will be high, your head pressure will be lower, not sure how clean your condenser coils are so its hard to say how high. Your amp draw on your compressor will be lower than normal. Also, when looking at the suction pressures, you have to keep in mind what temp the air hitting the evap coil is. If it is warm, that will make your suction pressure go up. Another way to check the vavles is to hold the suction line at the compressor when you shut it off. If the temp goes up the second you shut it off, this tells you the hot gas is leaking through your suction valves. You can also try to pump the system down, then shut it off and see how fast the pressure builds back up, this will give you and idea how fast it is leaking through. Let me know if you need any thing else, I'll be here.
seth

The reason you have high suction is probaly due to contamination in you a/c system. To clarify contamination, I mean water, other gases, or anything else, there only two things that should be in your a/c system, refrigerant and oil, anything else is a problem and will change your suction pressure.

If you can prove these items are true, then you need to examine that your condensor is cooling and condensing the high pressure gas, the tev is working correctly, and your high pressure is normal, and cooling is excellant.

Before you start checking pressures, you need to make sure that the unit is clean inside and out. You also need to know what the ambient temp is outside so you know what the pressures should read. Without this information, your info is useless to me. You need to know what your saturation temp is to determine if the head pressure is too high or too low. If the outside unit is dirty, you will have a high head pressure and low suction pressure. If the inside is dirty, you will have a high suction and a normal to low head. My advice to you is to clean first and then start checking temps and pressures. Otherwise you are spinning your wheels.

disconnect the blower and turn on the ac.see if the coil frosts evenly.when you had the system open,you should have changed the liquid line drier.