Williams walk in freezer ice build up

[Karl Hofmann]

I'm having a minor headach with a freezer used to store frozen pies. I was called to it just before Christmas with an ice build up issue.... Defrost it all, replace the drain heater and off we go....Or so I thought.

Just been back to it with ice build up at the front of the evaporator and the fan appears to be whipping up water and spraying it up onto the ceiling if the store where it forms ice drips... All the defrost elements are working but it seems like the water is originating in the coils..... I'm tempted to increase the defrost time and add a couple of minutes to the defrost drain down....And to fit a door switch to cut the fan when the door is open as they do open it quite often and for quite a long time when they are taking a delivery although the shop owner denies this

The freezer is run at minus 18c and is roughly 3000mm by 3000mm. The door seals appear to be good..

Any thoughts guys? Am I deluding myself that minor adjustments can solve this headache?

[chemi-cool]

Add a door switch that cuts the SV and evaporator fan on opening the door.
Set the evaporator fan to start only when evaporator coil is at -2C.
That should help for a start.

[monkey spanners]

Is the drain clear outside?

Had one last year where it froze up and backed up into the evap.

[Karl Hofmann]

Thanks guys, Chemi I'll see if there is an option to start the fan when the Evap hits a temperature and definately a door switch...

Spanners, thanks for that, it was pretty cold round about the weekend here I completely forgot about the termination of the condensate pipe and that is when the customer said he noticed the problem... How dumb can I be?

......Don't answer that!!!!

[chemi-cool]

karl, In freezers where I have problems with condensate water, I drop in the pipe, heating element [like door heater] with the lowest wattage and leave it energize all the time.

And if you can't program the way it should be, replace the controller with Dixell XB 500.

I did that on a Williams blast chiller.

[Karl Hofmann]

Thanks Chemi, sadly spending much money is not an option on this piece of garbage... It was bought second hand off ebay... I'm reasonably happy that it was the condensate outlet freezing in the cold weather and the water backing up...Ironically since most of my work is now gas fired heating, I'm usually anal when it comes to preventing freezing condensate pipes...

[tonyelian]

hi
you mention that ice build up @the front of evaporator you should take a look if it is a lack of refrigerant