Ice balls in evaps

[jan behnke]

Friga Bohn SKB 19 four Evap fans low temp application. Hi can any one shed some light on a fault I have, just in the process of changing a Evap in a low temp cold store due to ice balls in the coil, if you were to see the coil its like some one has been at it with a machine gun, ice balls have formed in the coil growing up to about 10cm to 15cm bending coil pipes and heaters, but no ice any were else, all defrost heaters were, working, set at –25C two coils in a store, the only difference with this coil and the one in the same room is the restricted air flow to the coil, if you were to imagine the room, the left side with the damaged coil is floor to ceiling with stock 7 meters high with a 1 meter air gap at the top, and a 2 meter zone around the coil, I suspect this is problem

[Peter_1]

Any possibility to take some photo's?

[jan behnke]

had some but deleted them, the ice is rock hard not like the normal ice build up on a coil i have never seen any thing like it before

[shaneIRL]

possibly defrost termination temp set too high, water in condensing into droplets, when refrigeration resumes they grow??? its a wild guess!. Is your drip time long enough?
what temp do your fans start up at after defrost? usually should be below -3C

[Abe]

Seems to be a " point" where the water is collecting......... on the coil.

Probably the copper bent or not round.......damming the condensate as it falls.

Then it builds up gradually into a ball

[jan behnke]

the coil terminates at + 10 the unit is controlled by danfoss adapta cool akv 11. the fins are perfect can not see how any water can collect in there, the problem started 18 mth's ago at the bottom but we managed to by pass that section on the coil, now it's moved up the coil hence the replacement ????

[chemi-cool]

the only difference with this coil and the one in the same room is the restricted air flow

I will look from different point of view. I think that some dirt in the coil, soak water at defrost and then it start to grow as the air moving slow through the coil.

In freezing coils you sould not have a space, smaller then 6 mm.

It might be too late but you should see into the center of the ice ball.

Chemi

[jan behnke]

CR.bmpWhy would it only effect one coil, four in total same conditions apart from air flow, I think it must be something to do with the air flow,two chambers with two coils in each the drawing is off sacks of frozen clam shells

[chemi-cool]

same conditions apart from air flow

I believe you are answering yourself.

Chemi

[jan behnke]

Some times if you are to close to a problem you can not see it, I would like to find out how the ice is formed, my be it is forming on dirt and growing like a pearl

[chillin out]

If you can get a picture of this, it would be really helpfull.

To be able to receive help, you must first help yourself