No expansion valve???

[buelldart]

Hi guys

This is my first post here and I gotta tell you that I don't know much about refrigeration.

I have a doubt about a recent walk-in cooler that I got installed just today (finally).

The walk-in cooler is aproximately 6 ft x 20 ft, 8 doors.

Just one thing about it: When the tecnician was installing it, he said the expansion valve wasn't working right, so he took it away, I mean he conected it directly without the valve, and he says he's gonna use a timer.

I don't know much, but that sounds fishy to me, like he's trying to save some money.

I have strong reasons to doubt of the ethic of this guys, we gave 'em the 80% of the money for the walk-in cooler and they installed it in 5 months, only after we arrived at their local with 2 trucks full of cops (haha, courtesy of a cop friend).

Anyway, that's life in Mexico but I'd like to know if that no-valve-only-timer things is just a cheap fix and I would end up paying later for that.

Thank you.

I hope I'm right posting this kind of question here.

[dsp]

Never heard of that before??

[chemi-cool]

Anyway, that's life in Mexico

Thats explains something but go know, you might be on the threshold of a new invention.

Keep us posted how does it cool.

[750 Valve]

Are you sure it was the expansion valve he removed? Its pretty darn crucial to the operation of the room. Does it get cold at all?

[chemi-cool]

I believe that if the liquid line is 1\4, there will be some kind of pressure drop in the evaporator and therefore some cooling,

The compressor will defiantly will be cold and the head pressure will be low.

[Peter_1]

If it was the exp. valve, then it will never work like it should Like 750Valve, one of the most crucial parts ion a refrigeration system.

[casstrig]

This system cannot work as without the drop in pressure after the expantion valve(this is its function)there will be no evaporation hence no heat absorbed,the compresor just pumping refrigerant with no cooling effect.That is unless he replaced it with cappillary tube which I dout his being cappable to calculate its length and bore size.

[buelldart]

Hi

Thank you guys for all your responses.

Following your comments on how it was not possible the cooling without the valve, I went to see what he did and aparentely he left the valve there, but added a few rings of cappillary tube as casstrig comented.

All that is what I can see without openind the fan, I dont feel confortable opening it since he made some changes (the cappillary tube connected with some other hardware) and those changes look like they're gonna break if I force the lid of the fan open.

The original valve was Danfoss, blue. I don't know if this would work, or if its recomendable the let it like that. It's is cooling, last night went all the way down to 30F and today its about 37F.

The doors are all wet, from the condensation and thats because it's pretty hot down here, but we specifically told them we wanted heated doors but i just did some research on the trash where they put the wooden boxes and it says NHG: Non-heated-glass.

Apparently I'm gonna have nightmares for a long time.

Thank you all for your responses and please feel free to laugh at me

[powell]

I think buelldart is referring to a temperature control. It makes more sense on why the tech would state that a timer would work (which is not the case).

The Danfoss TEV's we sell here the USA are not blue. The temperature controls are dark blushish/black.

[Plank!]

The Blue Danfoss component sounds like a solenoid coil to me.

[brunstar]

sounds weird and without an expansion valve it won't cool as you will get no pressure drop.....
i think he is having you on...this will also cause your compressor to pump liquid.......ummm don't think it is the EXV..

[round_the_rack]

Stories like this make me cringe. Was this a Mexican refrigeration local? I wasn't even aware that fridgies were organized down there.
As for the mechanic's actions; I can see replacing an expansion valve with cap tube, but as a temporary measure only. By your description, that doesn't sound like the case.

[buelldart]

Hi guys, thanks for all your responses.

I really don't know if it was only for temperature regulation or it was a replace for the valve that he added the rings.

And yes it was a Mexican refrigeration local, since I'm in Mexico. I'm regreting it a lot, I can't trust anything of the work now. In a point we made them sign a 2-year warranty but from these guys, a 10-year warranty is worth 5 cents.

One thing that's driving me crazy is the Non Heated Glass Doors. The condensation it's a lot.

We're 90F with 50% humidity but still, i've had lots of fridges with glass doors and never seen anything like that.

I took some pictures so you can see what I'm talking about, I just took them 5 minutes ago so the condensing unit pics are blurry since it's night time.



I'm thinking on paying another refrigeration business to come and fix everything.

Thank you guys for all your comments.

[buelldart]

I'm not allowed to post links here but I'm gonna take a shot I hope it doesn't get deleted

[a/c.king]

there is no such related issueu between tx valve and timer. its look like that the tichnicain playing games with u.but in refrigeration there is timer that is responsable to defrost the ice of evaporator.

[750 Valve]

I'll post a link up for you mate so all can see without typing the address.

Well thats some pretty shoddy work right there, everything from the room construction to the way the drain is (not) secured, I especially like the way he hung the evaporator...

http://s37.photobucket.com/albums/e6...view=slideshow

Incidentally that is a heated door insert you can see the wiring label in one of the pictures -
red - door heat circuit
white/red - door heat neutral
black - frame heat circuit
white/black - frame heat neutral
It is likely not wired up correctly if at all.


Now that last pic where you indicate what he added - that IS an expansion valve (TXV) the rings are a part of the expansion valve. With the right amount of careful bending of the copper tubes that cover will go back on.

[buelldart]

Thanks 750

Then the guy is playing games with me, unless he added that valve himself.

About the wires.. yes I thought that myself but doesn't the door need to be wired too? those wires go in the frame, so I would expect that the frame is wired somehow to the door. Anyhow it's not working, either the wired it all wrong or only the frames are heated -- incidentally the frames sweat too.

I added a few more pictures of the condensator.

I think I'll call someone else to come fix this thing. It's a headache.

Thanks again.

[Peter_1]

If you not already paid him, then I should send him a letter stating that his job isn't done the way it should be.

Never saw such a sweating doors.

I should contact in this case immediately a lawyer.

[Peter_1]

I already see fungus on the doors.

[750 Valve]

Open any door, about halfway down on the hinge side of the door you shoul see a cable come out from the frame and enter the door - this is where the doors plug into the frame to get power to run the heaters, some have their power cords routed to the top of the door but most are halfway down the door on the hinged side.

With hold any money you owe him and pay someone else to fix it, it may cost a little more but it sounds like you are dealing with a really dodgey individual. You'll have piece of mind knowing the job is done correctly.

[cookster]

doors need anti-sweat heaters and the frame on seperate circuit- as for operation of chiller how did he calculate load, size is very important. looking at pics evap could be flooding

[buelldart]

I still "owe him" 2000 dlls. Of course I'm not gonna pay him. It's an absolut mess. Everything is wet, costumers can't see a thing.

I sent an email to a sales rep of Anthony Doors to see if we can upgrade to heated glass doors. Of course, I would be dealing directly with AI.

It's very frustrating...

[kooler]

Well gents I've seen a simple ball valve act as a TEMPORARY metering device in a reefer system.. It's crude indeed but will work in an emergency, you just crack it open a little to create that pressure drop... cheers, kooler

[gallacher23]

without an expansion valve, you aint got a chiller. good luck

[icecube51]

wonder whats happened whit the LP/HP box ??
insulation on the tubes s***s to.seeing stuff i would rather not be seeing. pallet for engine hosting looks nice, for now.wonder wat happens to the unit wen it becomes rotten.
hope not all Mex techs are like that,ore the nightmare will only just begone.

sorry for you M8,keep on fighting

Ice

[Porkington]

I'd be contacting my solicitor.... the equiv . of HSE in Mexico and several of my largest friends to go and "see" him. For gods sake don't pay him anything else.

I'd be ashamed to put my name to that install.

And yeah 750.... the Evap hanging is the new Anti Vibration method!!!

[MOHAMMED ASHRAF]

It is very surprise news from Mexico.any way pls wait and see final result.who is don't know about working of exp valve.

[tomfagan29]

he's pulling your leg, thats for sure