Heater tape

[Grizzly]

Ok Doni
Simply put and preferably as near to the drainline fitting to the evap / cooler tray.
There needs to be a means of trapping some of the water that is being drained off.
Effectively sealing the drainline from the ingress of the (Higher Pressure ) warm moist air from outside.
Traditionally a P trap or S trap as used by plumbers is used by many.
A Plumber uses a Trap to stop Drain smells percolating back up and out of the plug hole.

Similarly a Refrigeration Engineer needs to. As I have said stop the air from outside the Refrigerated area being drawn up the drainline and meeting the drier and significantly colder air inside.
If you don't have a vapour seal all that will happen is.
Whenever the evap / Cooler is not on defrost the Air from outside will flood into the Refrigerated Zone via the drainline. You can even get ice crystal forming which will eventually form a blockage at the drain outlet.

crystals at iced up drainline.jpg ice crystals at drain mouth.jpg


This warm moist air even whilst sitting in the drainline can condense and freeze.
Simply put a wet seal as near to the drain tray but outside of the freezer envelope is absolutely necessary.

Basic stuff but many modern designers think they know better.

Hence the pictures from a 5 year old plant that freezes up all the time and introduces vast amounts of moisture into its store.
Due to Modern design ethics!
Still fighting to get mods done after nearly 5 yrs.
But Hey what do I know?

if you look at the photos you can see the gray green residue (Dust) that prevails in any cold store of sufficient size.
This dust which accumulates on the cooler fins will eventually be washed down the drainline.
Its a mixture of Cardboard, Concrete and pallet wood dust usually.
It's Humidity and temperature related.

As it flows down the drainline some is trapped around the heater tape.
Just like a tampon in a sewer!
A blockage will occur, the heater tape until it fails will create a polo mint type of effect.
Until the drainline eventually blocks!
These blockages electrically stress the heater tapes and cold spots are generated!
Drastically reducing the effectiveness of the drains to remove the collected moisture from the coolers.

None of this happens when you spiral wind around the periphery of the drainline. Its just a practical way of achieving what is needed without further obstructing the flow of the water which is draining away.
Don't forget to insulate the outside of the pipe afterwards.


Are people not teaching these practises any more?

Cheers Grizzly
PS 3mtrs is to long!