Air Conditioning - help - a/c pumps itself down

walked up on amana a/c condensor it was frozen
allowed it time to unfreeze
watching the pressures i noticed the unit is pumping itself down and freezing up
inside works fine.. blower runs no airflow restrictions
replaced high pressure line dryer.. didnt fix problem
replaced indoor evaporator coil w/ expansion valve
still does the same thing..
copper lines are not crimped
and the valves outside are not closed
but it acts like it is..
the lineset for this system is abnormally long.. probably over 100feet .. new construction company ran it all the way accross the house..
its a bleed over expansion valve i was thinkin maybe the lineset was too long but i dont know anymore
what else could it be?
thx

Where is it freezing up on you? Outside or inside?

What size line is it on both side?

well i havent located exactly where it starts freezing first
but it is definently upstairs
starts working its way towards the condensor
the lineset is a few sizes actually i guess with the combination of new home construction and bad planning they ended up running a lineset thats probably around 100feet long and a few different sizes
outside u have 3/8 and 7/8 copper lines
inside near the evap coil suction line moves up to 1 1/8
like i said its the longest run ive seen for a copper lineset

How many ton is the system? I think that this system is not made to run this long of a run.

I have never seen a unit that would allow that long of a run per manufacturer specs. What size is the liquid line? Is it 3/8 all the way?

its a 3-4 ton coil with the expansion valve
and the condenser is 3 ton
i know the lineset is too long even thought ive never measured it
and it would explain why size has become a critical issue because here in texas the weather is changing because its winter
and like i said the suction line changes sizes somewhere in the wall..
at the evap coil the suction line is 1 1/8
at the condenser its 7/8
ive gone in both addics of the house.. the lineset runs through both, yeah its that long.. it would be real easy to measure how long it is.. ill go ahead and get that out of the way..

How long does it run before it starts to freeze? Is there a sight glass on the liquid line? What are the pressures 10 minutes after startup and what type of freon? What is the age of the condenser?

just like pumping a condenser down
its instant
there has to be some sort of restriction
but ive pretty much eliminated that
so
moisture
or maybe the lineset is too long

I'd walk away from this job, and have the home owner go back to the orginal company who installed this. I am guessing this home is brand new?

Did you have your co-worker come out to the job and take a look it this to get a 2nd opinion? Pretty hard for us to trouble shot this on line with out seeing the job site.

If the install manual is there, look at it, and see the lineset sizing chart. If no info there, then contact the company and see what the linset limit is. I will want want to say that the system is NOT made for this long of run. Then it should go back to the builder/installer for this mistake.

problem solved
thx for your help anyway though
heres the scoop incase anyones interested
home owner called 2 different companys before us
they couldnt figure it out
somehow the low voltage wires got crossed between 2 different systems
expansion valve wasnt opening because it wasnt getting 24 volts ofcourse because the last company crossed low voltage wires!
troubleshooting usually comes very easy to our company
but fixing other peoples mistakes like this I have no expirence with, its a whole different ball game and follows none of the apparent logic im used to
i spent a long time tracking down a short that didnt exist, tied the two low voltage wires together to test for continuety and got nothing.. sob somebody tied these wires in the wrong place..

Gotta think outside the box man. Expansion valve,24 volts? You mean a solenoid valve? And why is there one on an air conditioner?