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smurphy
11-24-2005, 09:37 AM
just wondering how you guys install them.I understand that the more slope you have in a freezer drain is the best, but what about the ones that are like 5 years old and runs along the back wall of the freezer, then goes in a cooler then ties in with it.I've been using a heat tape called easy heat, wrap the drain line with it ,then insulate, wired in with the evap fans.Seems to work pretty good, but seems the heater goes out in about 5 years or so.

condenseddave
11-24-2005, 12:50 PM
I use 6W/foot tape, wrapped and then insulate the line with 3/4" wall armaflex.

I can't say we only get 5 years out of the tape, but the tape does fail once in awhile.

As far as a steep slope out the back, well, I've seen ones installed with 60 degrees of pitch freeze shut, too.

The ones that connect to a cooler drain, IMO, should be separated from it, and run out to the terminal drain separately.

frozensolid
11-25-2005, 03:36 PM
I have hade good luck with raychem heaters they self-regulate. But when ever possible I would solder (stay brite #8) the incoming liquid line to the bottom of the drain line and insulate. Worked best on hot gas defrost systems, but it did work on non gas defrost systems also. Think warm liquid.

[Edited by frozensolid on 11-25-2005 at 03:38 PM]

icemeister
11-25-2005, 05:56 PM
I use the Raychem heater tape as well. That's what Dave was referring to I'd guess because it's 6W/FT. I keep a coil of it in the truck along with enough self-sealing heat-shrink tubing to put a new heater together in a very short time. I haven't had one fail......yet. ;)

That liquid line soldered to the drain line works good although I rarely see it done.......and the ones I've seen didn't have any provision for removing the pan for cleaning or service without cutting the liquid line too. :(

frozensolid
11-25-2005, 06:29 PM
If done correctly ice all you need is a union on the drain line. The best part is never having a frozensolid :) drain line.

cyro
11-25-2005, 07:44 PM
I also have used the raychem heater tape, with 3/4 armaflex.

But I also use the 1/4" soft copper tubing heaters that you slide inside the drain tubing. I have never had one go bad yet, and very easy to install. still must use armaflex.

big ern
11-27-2005, 08:46 AM
The heat tape should be wired with the heater elements of the evaporator. They should only be energized durring the defrost cycle and not be energized all the time. That is why the tape may be failing so quickly. The tape should also not overlap upon itself. That will make it fail too. You should use a copper drain line for better heat distribution throughout the drain line. And should never insulate the drain line and tape with armaflex. It doesent help thaw out the drain line durring defrost, but will start one hell of a smoky fire should the tape fail from a short. Pvc drain line doesent conduct heat well so it is a poor choice in the walk in-freezer application. You still require a drain trap. Make sure it is out side of the freezer box in an area that doesent drop below freezing temperaratures. As far as running a heating element inside the drain line? It all depends how long the drain is; how much time and effort you want to put into it; and how often if at all will the drain plug up because of the tape, and other particulate matter gathering up somewhere in the line. Good luck.

icemeister
11-27-2005, 09:45 AM
The drain line heater for a freezer must be energized all the time and the line should be insulated. See Heatcraft's I&O Manual (http://www.heatcraftrpd.com/Maintenance/manuals/H-IM-64K.pdf) on page 9.

smilies
11-27-2005, 05:13 PM
Originally posted by big ern
The heat tape should be wired with the heater elements of the evaporator. They should only be energized durring the defrost cycle and not be energized all the time.

This is not true at all


Originally posted by big ern
The tape should also not overlap upon itself. That will make it fail too.

This is true



Originally posted by big ern
And should never insulate the drain line and tape with armaflex. It doesent help thaw out the drain line durring defrost, but will start one hell of a smoky fire should the tape fail from a short.

First part is a lie, second part is true.


All in all, I would not listen to big ern and do what others here suggest.

frozensolid
11-27-2005, 06:35 PM
I agree jerry except the part about over-lapping. The ray-chem can be overlapped, its cool stuff.

cyro
11-27-2005, 07:00 PM
I am old school, I have seen what happens when you overlap heat tape.

It may say it is okay in there instructions but I make it a point to never overlap it.

I guess this makes me old. when I won't change with the times. I have to go now and join AARP.




p.s. I'm not as old as Rayr

selfemployed
11-27-2005, 10:02 PM
If possible I trap outside of the freezer. Don't like tying into cooler drain line inside cooler but have some that were done that way. I use Frostex heat tape.

-80guru
11-27-2005, 10:14 PM
Run the heater tape along the bottom of the copper drain line all the way to the exit of the freezer. Use heat conductive paste for good thermal transfer between the tape and copper line. Energize heattape constantly. Insulate drain line with 1" thick armaflex, 3/4" thick minimum.

thegoodhumorman
11-30-2005, 02:34 AM
I once got to followup an install of frozen reachins-
ala Costco/Sams with the freezer consisting of
multi evaps in a walkaround box with plenty of
Anthony Doors for product access.
Clever factory engineer ran the drainlines right down the middle of the "box" and they put the heater inside it.
It was some whizkid design. You know whats coming...

Thats right. It got better- it was a mullion heater to boot. Nice loop, maybe 40 ft long total in each drain.
Lasted a few days at least. Engineers- LOL.
"Poor thing, probably kept up for the first mile or so...."

Convinced me that I have not, nor ever will have
seen it all.

Dowadudda
11-30-2005, 08:05 AM
Electrical Gray PVC with a braided heater wire inserted the length of the run. You can have these made to any length you want. I have done it and seen it in 1" and 3/4" and have had to do 25' runs. The trick is getting the length long enough to extend it's reach to the outside of the box.

Wire it to be on all the time.

Much cleaner look. Works Great. Does not look cheap and crappy either. I got this idea from a major manufacturer. I have not seen one I have installed fail yet. If it does fail, it's much easier to replace. It's also much easier to install initially. Copper, heat tape, then insulate. It's a mess compared to this.

I can't tell you how many plumbing white PVC runs with the heat tape wrapped around them I hav had to replace. I always come up on something like that and I just shake my head. It's only common sense that would not work.