I recently installed a new 5 ton Carrier unit Carrier and low side pressure is at 125 but high side pressure is at 425.
Then I measured the temperature drop on the inside unit and my pyschrometer indicates it 78.6 f with 41.1% humidity at the return and the temp probe indicates 53.6 degress Fahrenheit at the top duct. It's giving me a 25 degree temp drop.
Also this unit metering device has a TXV and I measured 106 temp on my high side line and if i convert 425 psi to temp I get 120 degrees farenheight.
Giving me 14 degrees Fahrenheit of subcooling.
The label say that the unit calls for 9 degrees of subcooling
Note that I installed unit Saturday and was hoping pressure would stabilize but it hasn't
Also this unit is new and I have not added any refrigetant. Do you think it might have been overcharged from factory.
The door to the air handler closet has not been installed. Not sure if this makes a difference.
Are you sure the TXV bulb is secured in the proper position?
If you're able to measure the amperage on the compressor and find it's high compared to the listed rating plate amperage, that could indicate you are overcharged.
I would also try to increase the indoor air flow to help reduce the temperature drop. 25F is high.
Air flow for 5 tons on a lot of residential equipment can be tough to get depending on the ductwork, filter arrangement, and unit itself. Not surprised if you don't have enough air flow with that 25 degree difference, especially if you're dealing with a single 16 x 25 x 1 filter.
Very possible the unit is overcharged, but I would first focus on getting the DeltaT in a better range.