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wackiejackie88
14-08-2012, 09:41 PM
Hello Everyone,

I have been having a problem with my drain line icing up, and making an iceberg in my freezer. I decided to enlarge the drain line and add a heat trace line inside the drain. I'm using 6w/ft Raychem heat trace.

My question is should the heater be on all the time or just during the defrost cycle?

The freezer has a paragon 8145-00 which terminals should i wire to?

Unfortunately, my fridge tech hates to be bothered with these jobs so I'm forced to do it myself.

install monkey
14-08-2012, 09:43 PM
keep the drain heater permananty powered,may be a bit under powered- usually around 30w per mtr

wackiejackie88
15-08-2012, 01:45 AM
Install Monkey, Thanks for the quick reply! Any idea which terminals to go to on the 8145?

Thanks again for the help, i appreciate it!

Grizzly
15-08-2012, 06:18 AM
Hi.
Basically you power the heater between the common neutral and term 3 which utilises the thermostat for its control.

I can upload details later if you wish.
Only I am on my way out the door to go to work.
Grizzly

wackiejackie88
15-08-2012, 03:38 PM
Grizzly,

Thanks for the reply. I got out my voltage tester and it appears #3 is normally closed. How would this keep the drain line heater on all the time? Also, there is no more room on the terminal board for #3.

#4 is hot all the time but i don't have an empty spot on the terminal board for it.

#1 is the supply, but also no free terminal.

Should i use a piggy back connector???


Thanks again guys!

chemi-cool
15-08-2012, 03:45 PM
I don't think you are doing the right thing.
By inserting the heat trace, you make the drain smaller, if you enlarge the drain pipe, I believe it will be OK.

wackiejackie88
15-08-2012, 04:41 PM
Chemi Cool, i did enlarge the drain. I went from 3/4" pvc to 1-1/2" copper pipe. And the drain on the pan was about 3/8" and i made that 1". Plenty of room now... :)

chemi-cool
15-08-2012, 05:15 PM
I would give it a try before inserting heat trace and see how it run for a while.

wackiejackie88
15-08-2012, 05:19 PM
Well when it was 3/4" that was after i enlarged it from 1/2" hose. It always ices up.

My problem is where to wire the heat trace to. Any suggestions?? Should i use a piggyback connector to give me the hot wire? I have 1 open terminal for neutral.

Grizzly
15-08-2012, 07:16 PM
Hi wackiejackie.
A stupid question I know. But have you proven there is a sufficient Fall along the drain line.
If any water stays in the drain line this will freeze and compound the problem?
Also where does the defrost drain line terminate?
Sometimes a simple water trap on the outside of the freezer helps as this will stop the warm air from outside being drawn into the defrost drain line / evaporator tray. Any moisture within this air will freeze and not defrost.

An internal defrost heater tape can be made redundant if a vapour trap is created and there is sufficient water flow from the defrost tray to outside.

With regard to my earlier post see attached.
However it should not hurt to have you trace heating on all the time, in fact it would struggle to work only being powered whilst on defrost.
Provided you insulate the drain line with armaflex or similar which I am assuming is already done?
Grizzly

wackiejackie88
15-08-2012, 07:28 PM
Hi Grizzly,

What do you mean by 'fall'? Is that pitch? If so it is pitched 45 degrees.

The defrost drain goes through my floor, into the basement and into a slap sink. And yes, i do have a check valve on the drain line in the basement stopping any warm air.

Thanks for the diagram. I actually found that one yesterday on a different website.

My problem now is just wiring the heat trace, i have spot on the terminal block for neutral but i dont have an empty slot for the hot. Should use a terminal splitter or piggyback connector to get that hot? Is that acceptable?

Yes, there is sufficient insulation on the drain line.

Grizzly
15-08-2012, 08:59 PM
Hi Jackie.
Yes, fall is pitch!
If it's all as you say then there is something weird going on.
Just where is the ice forming on your drain line?
More to the point where is the moisture coming from if your line is as free flowing as you describe?
Sorry to be so thick only I must be misunderstanding somehow!
Your trace heating is not a large load I assume?
Therefore you could attach as you say to the Hot wire.
Most we deal in use the evaporator fan supplies which usually have a junction box with spare room. On the end of the evaporator.
Basically wherever there is a convenient terminal block.

Only you or your electrician can decide as I don't know your system or what loadings you already have.
Being able to isolate the heater tapes is highly recommended also.
As already mentioned it is normal to have the trace heating on permanently.
Grizzly

wackiejackie88
15-08-2012, 09:28 PM
The old 3/4 pvc line wasn't pitched as much (maybe 20 degrees). I'm thinking maybe a drop of water was sitting in the elbow and freezing up? Maybe the -15f temp is too cold and the pipe wasn't warm enough to let all the water through?

First the line would clog and then the condensate would over flow. I figured the heater, 45 degree pitch and larger pipe would remedy this problem.

Yes, small load....its only 6w/ft trace and there is only about 2 feet used.

I just realized i could wire it separately from the time clock and go to the outlet next to the freezer since it will run 24/7.

Grizzly
15-08-2012, 10:07 PM
As they say a "problem shared is a problem halved!"
Hope you get there.
You are definitely on the correct path.
If possible use a copper drain line and then the whole pipe will absorb your heat from the trace heating .
Which will reduce even further the possibility of a freeze up!

Grizzly

wackiejackie88
15-08-2012, 10:21 PM
Already there with the copper! ;)

Thanks for all the help!


Off topic, any books you guys recommend that will teach me how to repair my refrigeration? I need to learn this! I've had enough of people doing things wrong and just not caring. There are very few people left that actually take pride in what they do.