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Installed new txv today, amazing i now have superheat... Thanks everyone for all your help

Originally Posted by Brad gall

Thanks for the input. Wouldnt i still have superheat regardless if its over or undercharged unless the txv is bad? also the subcooling was normal.
(non adjustable txv)

To test the TXV actally place the sensing buld in a cup with ice then warn it up just to determinate if the valve is responding, if the valve is stuck wide open like you are suspecting, why the liquid pressure is so high? if is full opened and its not overcharged.


I'm assuming the compressor is sweating , if you have a system overcharged or with airflow issues or a combination of both the refrigerant just past threw the Evap and does not have a chance to reach the boiling point to change states.

Thanks for the input. Wouldnt i still have superheat regardless if its over or undercharged unless the txv is bad? also the subcooling was normal.
(non adjustable txv)

OT 50F , suction is a way high, remove the sensing buld and warm it up, with ur hand that should start to close the TXV, IF it does not, valve need to be repraced or the head.

Also due the the low OT , the system might be overcharged, some extra refrigerant was added to compensate the low pressure caused by the low temp, double check air flowm 21F split temp, is a little in the high too.

Thanks again for everyones help I will find out today and let everyone know

Originally Posted by Brad gall

Everything is all new and the same brand.
I never trust the counter guy either i hope all the equipment is correct
Ill find out Monday. Im just not sure any other reasons i wouldnt have any superheat at all?
Also i thought if the bulb gets overheated it would close shut?
Im not to sure, Ive been in the field a while and havent experienced this problem ?? Thanks alot for your help and any other thoughts would be greatly appreicated thanks

Overheating it to the point of releasing the charge would close it off.

I doubt you overheated it.

Some responses are saying overcharge?Overcharge on a txv would havehigh subcooland low super heat

Is the TEV adjustable??? Just turn it in a little, if it is and see what happens.

Originally Posted by hewitt

with no superheat means evaporator is flooding.Therefore txv may be stuck open?

That's what I'm thinking also. With temps that low your suction shouldn't be that high. Some time you just get a bad part from the factory. Grab another coil from distributor and change it out.

Probly what u already posted ;soldering more likely

Anything that would cause that ? Another guy just told me he knows of 10 others D.O.A on. new install bad txv

with no superheat means evaporator is flooding.Therefore txv may be stuck open?

Thanks everyone for all the help I really appreciate it , IM going to make sure the coil/txv is really a match on monday. Id feel better if it was there fault instead of mine..
If anyone knows my coil is #end4x36t172 Arcoaire
condenser is #n4a330akc200 Arcoaire
I relize the coil is a 3 ton and condenser is 2.5 ton but they said it would work when i bought it and the older ones i know it removed humidity better that way

is this a 2 story house ?

I've seen couple times where one return grill is either blocked , clogged with dirty filter , had 2 filters with one being dirty , or was never even cut into the wall and had the flex pipe blocked off inside the wall !

I took my screwdriver , poked a hole into the drywall and saw the flex laying there .... whoops

Also you might check your static pressure and see what kind of air flow
You are supplying ur 3 ton coil

Mix matching can have this exact problem
High suction pressures
Low superheat

You might be way over 6000 btu mix matched.

Back in the days were 3 ton condenser was actually 36000 btu
You can get away with 1/2 ton
But if you look at some of these high eff unit
They get a higher seer rating by reducing comp btu.
That's why all 3,4,5 ton are not created equall

So back to ur problem
Let say ur 2.5 is not really 30k btu
All the sudden ur txv is feeding more refrigerant
Than ur comp can pump.
This will result in higher than normal suction pressure
At 70 indoor dry bulb
Ur suction is way too high. 47 coil temp.


I would go to supply house and check to see if this valve is the same if it was 2.5 ton
You might need smaller txv

Originally Posted by shaka

Ok
I'm not sure how long you been on the field
But my first rule
Don't trust everything the counter guys tell you.

Are they all new?
Furnace,coil,condenser same brand?

Everything is all new and the same brand.
I never trust the counter guy either i hope all the equipment is correct
Ill find out Monday. Im just not sure any other reasons i wouldnt have any superheat at all?
Also i thought if the bulb gets overheated it would close shut?
Im not to sure, Ive been in the field a while and havent experienced this problem ?? Thanks alot for your help and any other thoughts would be greatly appreicated thanks

Ok
I'm not sure how long you been on the field
But my first rule
Don't trust everything the counter guys tell you.

Are they all new?
Furnace,coil,condenser same brand?

Yes Gas furnace

Back up
Is this on a gas furnace?