My air conditioner was installed with two filter driers, does that stress the system

[CHEDDARINAGOAT]

Among the many mistakes the installer made they did not remove my existing filter drier, does this cause any extra stress on the system.

[paul52446m]

Among the many mistakes the installer made they did not remove my existing filter drier, does this cause any extra stress on the system.

since you probably can't check pressure drop across the two drier, you check the temp difference on both sides. Check the temp. drop across the indoor coil
to see what reading you get. Go from the return air to the closes supply air oping. Later paul

[CHEDDARINAGOAT]

It's interesting to learn that two driers can make checking the pressure drop difficult, The more i learn, the more I believe the company i'm working with is inept, that these machines have to be dialed in and adjusted to work their best, pretty much anyone can put one in, but it takes every step, no shortcuts to make it last.

So whether or not they get paid is going to depend on if i have to remind them of crucial steps, like the nitrogen flush during blazing, and i'm even thinking of going as far as charging them $100 each time i catch them skipping a step.

The house is well vented, all 6" ducts, two large returns

[HayZee518]

when you braze a line its best not to have any pressure in the line, i.e.: nitrogen. any pressure will likely cause blow holes in the joint. silver solder is normally used, however, a lower temperature brazing rod called sil-phos is better. It melts at a lower temperature and provides excellant joints. it is important to have spotlessly clean fittings and copper tubing. a flux is not required with sil-phos. after brazing the system is evacuated with a high vacuum pump. pump down to about 30 in Hg and let it sit for 24 hrs. if the vacuum doesn't rise positive then you are good to go for a re-charge. use a heated charging cylinder and a digital scale. make sure proper mineral oil, moisture free is injected into the lines. a restricted filter dryer should be replaced. merely adding a dryer in line with an existing one isn't going to solve anything.

[CHEDDARINAGOAT]

I found the true problem to be the plastic pan isn't suitably level. there is a railroad tie supporting one corner that it 1/2" above the concrete pad that supports the rest of it.
when i put force in one direction it feels quite firm, the plastic pan grips the machine well, and i can see why a level installation doesn't need to be bolted down. But if i rock it in the other direction it shakes and wobbles easily with very little force, like a chair on uneven legs.
So I'm going to take the warped plastic pan, place it on flat concrete, prove my point, and not pay a thing, infact their getting a bill, i should not have to educate myself in home repairs to get a quality job the first time, thanks everyone for your help.