FF lineup; what kinds of temps are we looking for in Ice Cream??? ....

[R12rules]

I go into the store and the manager nails me for questions about his soft ice cream.

I have zero history on his FF lineup for ice cream. Even though the log is filled in in the motor room, it does not tell the whole story.

I just know summer is about to break lose and we have soft ice cream in this one store.

So I went thru each door and measured the discharge air temps ever so often.

On this line, I was getting between minus 19F to ZeroF. All on the same circuit. It just went progressively.

Shouldnt they all measure the same?

And .. since we are talking ice cream here, dont we need something like a product temp of minus twelve or minus fifteen?
So a minus nineteen is really nothing then ... is it? It is just not towing the load then .... hmmmmmm ....

[smilies]

Uneven temps in a circuit is usually the txv screens.

Is there a refrigeration schedule in the motor room? That has the all the info you can want.

Required temps vary chain to chain. For us, Safeway's want -12, while Kroger owned stores want -5 for RIIC and 0 for RIFF.

[R12rules]

AAAAAAhhhhh sooooooooooo ..... yes ... the printed schedule up on the wall.... yes...


However, for the most part ... those things are no longer readable. They are way gone faded out.


TX screens, yes I can check those. Thanks.

[smilies]

Originally posted by R12rules
AAAAAAhhhhh sooooooooooo

Did you just call me an a$$hole in Chinese?http://members.fortunecity.com/initzero/pages/smiles/happya/bigtongue.gif

[condenseddave]

Originally posted by jerrycoolsaz
Uneven temps in a circuit is usually the txv screens.

Is there a refrigeration schedule in the motor room? That has the all the info you can want.

Required temps vary chain to chain. For us, Safeway's want -12, while Kroger owned stores want -5 for RIIC and 0 for RIFF.

You're assuming that the liquid lines are all piped correctly in the cases.

Stop that.:p

[mccool]

If you have a # of glass doors on the same system, and they are running progressively warmer down the line, then # 1 to look at is receiver level and piping if both are good then look at tx screens.Easier to look for the obvious before goin to pumpdown mode.
Every rack has a system that will be the first to alarm or warm up on low liquid, figure out which one and why. Sometimes a good look at piping can correct as Dave mentioned. Without a low liquid alarm, your first indication of a leak is usually a high temp. alarm on the same system first.

GO Flames Go

[frozensolid]

Most markets I know of shoot for -25 evap for ice cream.

[condenseddave]

Originally posted by mccool
Without a low liquid alarm, your first indication of a leak is usually a high temp. alarm on the same system first.


Generally referred to as an Oh **** condition.

[icemeister]

Originally posted by R12rules
AAAAAAhhhhh sooooooooooo ..... yes ... the printed schedule up on the wall.... yes...


However, for the most part ... those things are no longer readable. They are way gone faded out......

You should be able to get this stuff from store engineering. Somebody has copies of the original refrigeration schedules and system plan drawings sitting in a file somewhere.

The chain I worked for had poor communications between the Construction/Engineering and Store Maintenance departments.......I was in Engineering and went out to survey a store for a proposed expansion where I ran into one of the refrigeration techs from Store Maintenance. When he saw the original piping plans and original Hussmann schedules I had brought with me he nearly threw a fit.

It was the same as you describe, the original plan on the wall was totally faded out and the schedules that were to kept with the racks were long gone missing. :(

[shaun66]

I run ice cream doors at -13, ice cream wide island at -25 ( with a sattelite). I float the suction from the ice cream doors, float the sattelite suction from ice cream w/island

[R12rules]

I see "Oh ****" conditions often.

I was just recharging the A/C for this one store today when I noticed the liquid level in one system, unrelated to A/C was seriously low on gas.

I had authorization to do whatever I needed in order to bring up the A/C. But not any other system.

And I knew this low receiver would be giving us a call some late night ... so I stelthly dumped a bunch of freon in there ... whilest adding gas to the A/C system.

That gas is going on the charge for the A/C.
Gotta be sneaky sometimes. Corperate dont know what's best for their own good.


On these stores, on the MT meat racks, the deli cooler box is usually the first to show signs of low charge.

So whenever I get a call for a store with a deli cooler down, I just drag in two shopping carts loaded down with refrigerant. 200 pounds of R-22 to the rescue.....:D

[oly]

Might want to check for leaks after putting in 200#, or is the store to cheap to pay for a leak check. It sure would save them money in the long run.

[refer dude 2479]

Originally posted by oly
Might want to check for leaks after putting in 200#, or is the store to cheap to pay for a leak check. It sure would save them money in the long run.

If you have your EPA card you know that the leak must be found and fixed. Don't give the store the option not to.........

It could be your ass in the sling

[condenseddave]

Originally posted by refer dude 2479

Originally posted by oly
Might want to check for leaks after putting in 200#, or is the store to cheap to pay for a leak check. It sure would save them money in the long run.

If you have your EPA card you know that the leak must be found and fixed. Don't give the store the option not to.........

It could be your ass in the sling

I can't believe someone would buy that quantity of refrigerant and not ask where it had gone.:confused:

I never, ever "ask" to leak test. And I leak test a LOT.

You're reading the ramblings of a guy who burns up more leak detector sensors than most large companies...:rolleyes:

What's a couple hundred in labor to leak check compared to tens of thousands in potential loss?????

[R12rules]

Yes I do leak check.
This customer has a form we must fill out whenever we dump in freon. (or a blend ... for that matter).

I work hard at finding whatever I can for leaks. I dont like the idea of dump and run.

I also dont like surprises. And in the past, I have been surprised by a leak or two which came back to haunt me.


(that was cute ... "if I have my EPA card")

[r22coolguy]

R12Rules,
Try to shoot for -8 to -12 on glass door sets. A couple of other ideas, if there is one controlling case, make sure it's txv is leaner, so it pulls down last. Normally the stubs should be piped middle of the line-up. Does this lineup get prgressively warm the farther away from the stubs? If so I agree check the liquid level. Also check defrost, sometimes the lineup is broken into multi circuits, you might ahve an issue there.

[oly]

Dave, ever not find a leak! one of those that might be in the overhead, or underground. Is this not a potential for increased labor? just curious.

[smilies]

Originally posted by oly
Dave, ever not find a leak! one of those that might be in the overhead, or underground. Is this not a potential for increased labor? just curious.

I'm not Dave, but I'll answer anyways. Those are more difficult to pinpoint but it can be done. Run your leak detector (H-10 in my case) at the start and end runs of that circuit. If your lines are insulated well like they should be, the gas will travel until it can escape. If it's the liquid line, look for oily areas above or stains on the floor or ceiling tiles.

If you're still in doubt about underground linesets, cut and pressurize the s.o.b.

[frozensolid]

I have found leaks in overhead piping to be very rare. Most are cause by poor installation practices. The occasional rub-out from a un-saddled pipe on a hanger.

The underground however is another story. It is more like swiss cheese than refrigeration piping. I do not believe I have ever seen a good underground system (although I have an idea for a method, I believe could be successful).

Most leaks I have seen, have been at rack, or the case/box.
But as I have said before, I have not seen it all either.

[stenfam]

just reading the threads..

whats your idea?

dan

[frozensolid]

Most U.G. leaks I have seen have been rubbouts, or lime corrosion. These occur in uninsulated lines or lines that have had their insulation torn, while being pulled into the U.G tubes.

My idea is to the encase the lines and insulation with 8 or 10 mil marine shrink wrap (the stuff they cover boats with for shipping). I believe this would make the lines easier to pull, and provide protection against tearing the insulation.

I think both liquid and suction lines should always be insulated in the U.G. I have seen many cases where insulation was in the specs for the job, yet it was not used. Many times sleazy contractors pull the copper tube, then put one piece of rubber on each end. Giving the appearance of proper installation. Their long gone, when it leaks a year down the road.

It would cost a little more to do this. Though It would be a lot cheaper than losing two or three hundred pounds of gas, and repulling lines.

[refer dude 2479]

Most of the big chains here spec that all underground lines be insulated, both liquid and suction, and then the lineset is run inside of 6 inch pvc. This started about 15 years ago for stores that were buiult near the bay. (SF Bay) The salt water would leak into the soil and eat the pipe in no time at all. At first the pvc thing was time consuming, but now most big stores are doing it and the installers have gotten quick at fabbing it up. Not much pipe goes into the ground here anymore. Only the pipes that can not come from the ceiling. Another advantage of the pvc is leak checking the underground. If there is a leak there is a 6 inch hole to sniff with your leak detector, but underground leaks have all but vanished in the new stores.

[icemeister]

In the olden days, circa 1950-1960's supermarket under-floor piping was typically run in accessible, but covered trenches or else in "orangeburg". It's that old style composite black sewer pipe. There were pull-boxes every 50 feet so you didn't have any underground joints in the soft-drawn copper. This was in the New England area, so I can't speak for other areas. I think the switch HD pipe and to Schedule 40 PVC came along in the 70's and then in the 80's we were using SDR PVC.

Anything direct buried w/o insulation was just suicidal, the insulation just prolonged the agony of eventual death. Everything alway went overhead unless it couldn't be avoided. It's just seems today the "suits" don't mind seeing boxed-in piping risers as much as they used to.