I think the standard setting is 40 min. The initiation/termination control determines the length of each defrost.
I went on a walkin freezer call today, and found the following. iced up big time.
found defrost heaters burned out, and the time clock had just been replaced a week ago by one of my competers.
the defrost time clock was set for 60 min. every 6 hours.
I set the times 25 min. every 6 hours.
this is on a +5* box. with A Larkin Heat Craft Coil#ECP62ooBJ with 5630 watt 208/240 volt heaters.
Question! what should the clock time settings be for this application?
Thanks.
I think the standard setting is 40 min. The initiation/termination control determines the length of each defrost.
Be safe not fast. body parts don't grow back
An old Kelvinator handbook recommended three 36 minute defrosts a day. to be at times when door(s)least opened and closed. Hope this helps.
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One thing you need to remember is that "Standard defrost times" are a good thing to know.....and a good place to start. However, each system is a little bit different. Depending on how the evaporator is located in the room, how much infiltration you have, the number of door openings and how long they're open, the RH where you're located, etc. In addition, one thing the service tech doesn't have information on is how close was the system sized to the actual load, or, how much the load has changed from what it was designed for since installed.
I've said all that to say this, 40 minutes is a good place to start, and may solve your problems. But if it doesn't, you can adjust the number of defrosts / day and time of each to match your particular application.
Defrost times at 40 minutes is a great place to start. All of the freezers we have are set either for 35 minutes 3x's a day or 45 minutes 2 x's a day. We try to keep the initiation time during the off peak times that the employees are in and out of the box. That way the freezer is in defrost for the times the doors are closed the most to retain temperature. Also we had some freezers that were set up with a manual temperature termination setting and were coming out of defrost on temperature too soon, and would not give the heaters enough time to defrost the coils. Some systems are tempermental and trial and error are your best friends.
Thanks a lot,Much appreciated.
The original setting of 60 min. Duration every 4 Hours should be fine.Make sure the termination is working properly. 25 min. is probably too short to allow the drain pan to warm up.
a lot of this depends upon what the product is.
For a dairy product ... I would go maybe three times a day.
A coil should defrost within fifteen minutes. The outside max should be twenty minutes. So I set my clocks to 25 or 40 minutes, depending upon the scenario.
Meat or something that is going to freeze hard, I would go more frequent than just three or four defrosts a day.
But unless you have either a high traffic useage or leaky door seals or high humidity outside the box ... or the product is coming in with high water content ... and being frozen in there ... I would not expect your application to need more than four defrosts per day.
If it does, and the applications I listed are not in play ... then there is seriously something wrong with the way the defrost system is working. (NOT working... I should say)
Wrong thermo-disk
Wrong location for thermo-disk
Not enough heat from the heaters
the heat from the heaters NOT contacting the coil properly.
Pluged drain pan. (non-ice)
pluged drain line, ice forming. Drain line heaters not working.
Drain not trapped, pee-trap .... that is.
Oh .. and make sure your defrost termination switch isnt prematurely killing the defrost and sending the clock back into the freezing mode.
I always wanna say something here about the evap fan delay ... but I dont think the need is there. I think you got it covered.