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View Full Version : Evaporator Defrost Conversion



jakb21599
08-04-2011, 10:26 PM
Hello friends, I have a Bohn Evaporator, model # BHA630CTA It is currently an air on defrost system. I need to convert it to electric defrost because it loosing temp in the cooler during the defrost cycle. The customer has increased load and the system now is doing all it can do to keep up. Their is a lot of moisture in the air during the pull down phase which is causing the coil to freeze up because it is running extended times with out the needed defrost cycle intervals just to try and keep product close to temp ( 35F). So i am looking at installing electric defost on evap because the customer does not want to add another unit in the cooler to assist with pull down.
So my question is this. Does any one know what type defrost rods or strips and how many is needed for this type evaporator? I need to know what defrost rods to get and how many it will take to get a good fast defrost in the shortest time possible. Thanks for your help

monkey spanners
08-04-2011, 10:41 PM
Have a word with your Bohn wholesaler to see if they list defrost heaters for it, it may be a similar evap to one used in freezer applications for which heaters are available. This would be your easiest solution.

I'm not sure it will help much in combating the problem, the defrosts will be quicker but you will also be putting a lot more heat into the space, but i could be wrong.

Jon :)

jakb21599
09-04-2011, 12:53 AM
I have already spoke to them and they said they do not offer them for that evaporator nor would they give me any help in determining what kind and how many was needed to defrost coil :mad: So i`m having to try and get information from people in field that might would know

jakb21599
09-04-2011, 11:04 PM
Mainly i just need to know how many defrost rods it would take to get a good defrost in the shortest period of time and around what wattage to use

monkey spanners
09-04-2011, 11:44 PM
If the evaporator is not desinged to have them fitted, where are you going to fit them? And where would you be if it caught fire or such? (i'm thinking of the USA's reputation for suing everyone)

Might be better to walk away from this one.

But to answer your question, find a similar duty evap that does have heaters, then find out the wattage and quantity.

I wonder if hot gas defrost might be a better option?