help evp feezing

[newbeetech]

evep coil is freezing? i wrote a long question but lost it so i will try to make this short must be on the field, anyway coil is freezing no restrictions 20sh and 40 sb when i hold the bulb of the txv the psi are where thay soppos to be ,

[rayr]

If one of my guys came to me with this porblem and that amount of information for diagnosis he would be looking for another job.

[frigetater]

we need a little more info there fella

[ar_hvac_man]

?

[artman934]

umm, are the filters clean?, how about the evap coil? what pressures are you reading in your gages and what kind of system is it?

[newbeetech]

sorry guys for some reason, this site does not let me ask this question in a ling form , i traied about 3 times sorry !!!

[icemeister]

sorry guys for some reason, this site does not let me ask this question in a ling form , i traied about 3 times sorry !!!

Are you using the "Quick Reply" or "Post Reply"? I'm not sure but the quick reply may be limiting how much you can post.

[The Doctor]

a ling form ???

a long form???
wudju talkin' bout willis?
what evaporator? what blower? what a machine! need....more....info...

[Yuma]

newbeetech you have posted more then 70 times?
First off is the evaporator in a medium or low temp unit?

That will help us start. :cool:

Also take rayr's post to heart.


Yuma,

[newbeetech]

let's try it aging, working on a I.C.P COMMERCIAL package unit that usto be orfice metered at the inlet of the evep coil the guys before me removed the orfice ,about 12 of them,becouse the orfices had plugged up with ,i bilieved was the break down of the filter drier on the liquid line thus freezing up the evp coil thay installed a .T.X.V valve with 3/16 cap tubes, unit never really worked it was/has benn freezing up , so i started from scrach and replaced the txv valve cleaned the coils cleand fan and blower tighten the belt replaced filters checked the intake and returned . i mean i looked for any ristrictions. low side psi is at 20 and hi side is at 175, it's not low on freon, i checked ,P.S. i took the bulb from the txv and helded in my hand and walla the psi raises to 65/250 , what the heck is going on?

[len]

is this a cooler, a freezer,an airplane or what,you have to post better info than that,be patient go back, and get all the info,(hint) what type of refrigerant,what size compressor,serial#model# voltage .etc.etc.ya get it now go back and do it right.

[icemeister]

Is this TEV externally equalized? If it's an internally equalized valve, the pressure drop through the distributor tubes tubes and the evaporator may result in a similar condition.

[newbeetech]

this is a roof top a/c for a 25x12 bakery room r22 freaon 4 deck ovens and 3 proofers very hot room temp could reach 200 degrees if a/c not working, with an external equelizer , compreser fla is 19.5 pulling at 16.5 amps super heat at 30 but 20 psi and subcooling at 40 with 150 psi i=on my hi side.

[the mojo]

Sure would like to know the heat load in a 25X12 room with 4 deck ovens,3 proofers and 1-2 very hot and mad bakers. Just a guess +160k/hr.

[yotaman16]

let's try it aging, working on a I.C.P COMMERCIAL package unit that usto be orfice metered at the inlet of the evep coil the guys before me removed the orfice ,about 12 of them,becouse the orfices had plugged up with ,i bilieved was the break down of the filter drier on the liquid line thus freezing up the evp coil thay installed a .T.X.V valve with 3/16 cap tubes, unit never really worked it was/has benn freezing up , so i started from scrach and replaced the txv valve cleaned the coils cleand fan and blower tighten the belt replaced filters checked the intake and returned . i mean i looked for any ristrictions. low side psi is at 20 and hi side is at 175, it's not low on freon, i checked ,P.S. i took the bulb from the txv and helded in my hand and walla the psi raises to 65/250 , what the heck is going on?

Ok first off this is the refrigeration & ice making section.. Second how do u know its not low on gas? It should be around 68 psi. What do u mean 3/16 cap tubes? To me it sounds like your best bet is a new unit seeing this one seems to be a hack job... Im not a fan of ICP's at all nothing but bad expericences with them. 3 out of my past 4 The compressor was running backwards, althought the tag says factory synchronized with blower motor and the blower was in the correct direction.

[hvaccop]

Have you tried adding any charge? With that much subcooling sounds like a restriction. Is the external equalizer line kinked or otherwise stopped up?

[300 Win Mag]

Is the TXV Power hear Rated for R-22 or R-12? Sounds like wrong power assy. That is why when you hold the bulb in your hand the pressures go normal.

[hvac_superman]

I think hvaccop may be on to something. Is the equalizer line clear.

[fl_dude]

It sounds to me like you have an air flow problem with the evaporator. If I was looking at this unit, the first thing I would check is how clean the coil is. Then I would check the blower motor draw amps, I'd expect to see at least 2/3 of the RLA, if its lower and you have a sheeve, adjust it, if it has a worn belt replace it, worn belts do slow the blower wheel. The next check I would do is check the delta t across the coil, I'd be looking for 15f to 20f. More than 20f, and you have to little airflow.If I had 14f or lower, I would change the TXV making sure it is the right size.
Hope I have gone some way in helping you fix this unit, or these tests has actually helped you find the full problem... keep us posted.

[Makinice]

After replacing the 12 "orifices" with an expansion valve due to being "plugged", was the system flushed?