Reply to Thread

Originally Posted by UmmScott

What he needs to do is suspend 2 hair dryers in the air behind the evap coil..
There..

No more frost [emoji23][emoji23][emoji23][emoji23][emoji23][emoji23]

Sent from my SM-N920V using Tapatalk

TimeClock would be ideal also ,, don’t want to waste Energy Defrosting if we don’t have to.

What he needs to do is suspend 2 hair dryers in the air behind the evap coil..
There..

No more frost [emoji23][emoji23][emoji23][emoji23][emoji23][emoji23]

Sent from my SM-N920V using Tapatalk

I personally know of 1 freezer coil that never frosted over and held good temp. It was the same setup with a cooler first then the door to the freezer.
I checked it frequently in sure amazement. Can even begin to comprehend it.

Freezer
R-134A
No heaters
2 weeks to freeze up
Supposedly a Occupation: HVAC Contracting

I don't think it could get near Zero.

I also don't think we'll ever know!

This has my curiosity as well hopefully the op will return with info. I hate it when a thread gets started and then dies without closure especially the weird ones. I equate it to giving a girl your phone number at the bar after you seem too hit it off ah maybe I need to get a life

Is this Fixed ?

I have heard of Plant Operators but this is just strange ,,, Manual Defrost Every 2 weeks ?

This is a joke, right?

A freezer with no defrost running for two weeks before icing up?

Wrong refrigerant and wrong evaporator. Probably wrong condenser too.
Propose actual freezer equipment.

Originally Posted by pecmsg

You are kidding right!

Omg, i have to laugh. Reminds me of the time i showed up to find a freezer converted into a cooler. Do what i did, run.

Defrosting walk-in freezer

Originally Posted by crazzycajun

If I’m reading this right there a freezer and cooler combo but no door separating the two and the freezer has no defrost? I’m with 2saac about being hot gas at one time. M#’s are a must especially in this story what or how is the customer using this product and application.

Some freezer doors are accessed from inside the cooler. I'm assuming that is what they meant. You know what they say about assumptions though...


Sent from my iPhone using Tapatalk

Let's get back to the -34º F evaporator temperature.

If so; no wonder the bastard accumulates frost! <g>

Is the freezer's suction pressure running at 12" vacuum?

And: what is the suction superheat?

PHM
----------

If I’m reading this right there a freezer and cooler combo but no door separating the two and the freezer has no defrost? I’m with 2saac about being hot gas at one time. M#’s are a must especially in this story what or how is the customer using this product and application.

Have you looked into if this is a new problem or has it just recently become an issue? I'm just curious why they haven't resolved the issue yet if it's been going on for a long time. As to the solution... See any of the above.


Sent from my iPhone using Tapatalk

Well; it can be Made to defrost. How depends on how interested you are.

The evaporator can have electric defrost rods grafted onto it.

The existing evaporator can be replaced by an evaporator with electric defrost in it.

Both will require adding the power to operate the heaters.

Hot gas defrost can be added to the existing system.

Reverse cycle defrost can be added to the existing system.

Is there a tee of any kind near the TXV?

Is the drain pan heated?

Is the drain line heated?

PHM
---------------

Originally Posted by Bugslugger

I inherited a customer who has a 8'x10' walk-in refrigerator with a 4'x8' walk-in freezer in the back; 2 separate refrigeration systems. The evaporator on the freezer part apparently wasn't designed for use as a freezer because there's no provision to defrost it and the condensate freezes into a solid block of frost. It maintains -5f when the coil is clear but when it's totally frozen over it won't--surprise surprise. So what I've been doing is using a solution of propylene glycol that's supposed to have a freeze point of -30, heating it up to ~130f and, using a bug sprayer, going in and defrosting the coil. It works fine for about 2 weeks then frosts over again. I didn't know where all the moisture was coming from for it to frost over like that so I scraped a bunch of it off and let it melt. What I discovered is the frost is frozen propylene glycol! The evap temp is around -34. The system is using 134a.

Any suggestions? It's in a cooking school so I really can't use anything that might contaminate the food.


Rich

So the freezer's suction pressure is 12" vacuum?

What is the suction superheat?

PHM
----------


r

Originally Posted by Bugslugger

I inherited a customer who has a 8'x10' walk-in refrigerator with a 4'x8' walk-in freezer in the back; 2 separate refrigeration systems. The evaporator on the freezer part apparently wasn't designed for use as a freezer because there's no provision to defrost it and the condensate freezes into a solid block of frost. It maintains -5f when the coil is clear but when it's totally frozen over it won't--surprise surprise. So what I've been doing is using a solution of propylene glycol that's supposed to have a freeze point of -30, heating it up to ~130f and, using a bug sprayer, going in and defrosting the coil. It works fine for about 2 weeks then frosts over again. I didn't know where all the moisture was coming from for it to frost over like that so I scraped a bunch of it off and let it melt. What I discovered is the frost is frozen propylene glycol! The evap temp is around -34. The system is using 134a.

Any suggestions? It's in a cooking school so I really can't use anything that might contaminate the food.


Rich

Originally Posted by Bugslugger

I inherited a customer who has a 8'x10' walk-in refrigerator with a 4'x8' walk-in freezer in the back; 2 separate refrigeration systems. The evaporator on the freezer part apparently wasn't designed for use as a freezer because there's no provision to defrost it and the condensate freezes into a solid block of frost. It maintains -5f when the coil is clear but when it's totally frozen over it won't--surprise surprise. So what I've been doing is using a solution of propylene glycol that's supposed to have a freeze point of -30, heating it up to ~130f and, using a bug sprayer, going in and defrosting the coil. It works fine for about 2 weeks then frosts over again. I didn't know where all the moisture was coming from for it to frost over like that so I scraped a bunch of it off and let it melt. What I discovered is the frost is frozen propylene glycol! The evap temp is around -34. The system is using 134a.

Any suggestions? It's in a cooking school so I really can't use anything that might contaminate the food.


Rich

You are kidding right!

Doesn't make sense. If there is no electric defrost, are you sure it's not supposed to be hot gas defrost?

Get an evaporator with electric defrost.

Problem goes away.

Sent from my SM-N920V using Tapatalk

Defrosting walk-in freezer

I inherited a customer who has a 8'x10' walk-in refrigerator with a 4'x8' walk-in freezer in the back; 2 separate refrigeration systems. The evaporator on the freezer part apparently wasn't designed for use as a freezer because there's no provision to defrost it and the condensate freezes into a solid block of frost. It maintains -5f when the coil is clear but when it's totally frozen over it won't--surprise surprise. So what I've been doing is using a solution of propylene glycol that's supposed to have a freeze point of -30, heating it up to ~130f and, using a bug sprayer, going in and defrosting the coil. It works fine for about 2 weeks then frosts over again. I didn't know where all the moisture was coming from for it to frost over like that so I scraped a bunch of it off and let it melt. What I discovered is the frost is frozen propylene glycol! The evap temp is around -34. The system is using 134a.

Any suggestions? It's in a cooking school so I really can't use anything that might contaminate the food.


Rich