Silicone Spray to reduce AC freeze ups?

I have a walk-in fridge that is prone to freezing up during the summer due to high humidity. I've done various things to improve the situation but have a specific question regarding advisability of using silicone spray (or some such product) as a way to reduce the moisture and then ice on the evaporation coil.

Any specific experience?

Any thoughts/suggestions related to the above?

Your help is appreciated!

It doesn't prevent ice formation, but spraying with silicone can make defrosting easier.

Geez, that would help!!!

Do you have some experience with that? Any gotchas or problems with it?

can you just put a dehumidifier in there?

I read somewhere that you can mitigate icing problems by installing an auxiliary fan to move more air past the evaporator coils. I think that you might also be able to use a timer to force a defrost period. It would probably require some experimentation to find the optimum setting, but I think it would be worth a try and the timers are cheap. Maybe something like 1/2 hr off and 2 hrs on for starters would be something to try. You can buy cheap timers at Home Depot or Lowes for about $10. I have not tried this, but it seems like it ought to work. How well, I do not know.

you cant fix it and it will just get worse, I will be there sunday to take it off your hands and scrap it for you just have out in the driveway and I will pick it up for you!

I second an auxillary fan blowing on the evaporator coils if you can. also, you can get some desiccant buckets and place them inside the box. you can make them cheap with 5 gallon buckets filled halfway with silica gel.

There has been a fair sized fan running continuously for quite a while...and it helps but does not solve the problem. Of course, any progress is good progress.

By the way, if I'd know how much hassle this would turn out to be, I would not have built it. And, if you want to take it off my hands...its gonna be more trouble than you're planning. But, I haven't given up yet.

Yes, I've tried the dehumidifier. They create heat you know. Didn't work.

Silica Gel works in a contained space, like my earlier freezer; but, with an active air flow over the coils, the freeze up occurs before the gel can function.

Back to the silicone spray - any problems with this? (remember any progress gets me closer to my goal, and/or makes the situation better. The plastic air curtain made things better too.)

Thanks

I would at least give the silicone spray a try and see what happens. How well is the walk-in sealed up? Anything you can do to minimize air leaks will help reduce the icing. This may fall under the stupid questions heading, but I'll ask anyway. Does the AC unit have a "vent" mode where it could be drawing in outside air? If so, are you certain that it's turned off? Not all units have this feature, but some do and it's not always clear which way to position the control lever that operates the vent. How long can you run the unit before it begins to ice up? I still think that forcing a defrost cycle occasionally using a timer might be the solution.

Some manufactures have 'add on' thermostats that you clip to AC evaporator coils that turn off the compressor when it starts to freeze up. If your appliance parts repair company can't help you try something like a Ranco.

You want to fix the problem? Take a look at this product: CoolBot

I saw this before (I'm not affiliated in any way) and it seems it might work really well for your situation. The way I understand the way it works, the unit monitors the room temperature of your walkin, monitors the temperature on the cooling coils and then can apply heat to the AC coil sensor to trick the AC into doing the task without freezing up. They have a good description of the unit on their site.

Something to consider.

Edit: I tested the link and it took me somewhere else. You might have to copy/paste the URL in a new browser. http://www.storeitcold.com

Another thought. Try this URL http://www.franklinbrew.org/members/sj/walkin.html It might work for you.

This AC is a new, cheap, unit and does not have a lever for outside/inside air. The thermostat is bypassed and is driven by the Ranco thermometer.

The unit is now VERY well sealed, capable of withstanding a cat 5 hurricane.

The water/humidity enters when I do. It is truly surprising how much water is contained within that space (even being careful to close the door behind me). Amazing. Of course, if I don't enter it at all there is zero water kicked out of the AC.

The good news is that the air is already getting drier; but, this is not what I had anticipated. (The unit was built last December and there was a very minimal problem then.)

I'm thinking silicone spray is next.

Maybe one of these days I'm going to have to invest in a better AC unit...dunno.

Thanks

Check my post at the end of page one. A added a 2nd after thought.

Have you considered using the defrost timer/burner/sensor from a refrigerator? It would be fairly straight forward to hook up if you are at all familiar with working with electrical.

It kicks on a small burner, about 18" long, that sits below the coil every 8-12 hours, and only if needed. The sensor, which simply clips onto the coil, tells it if the coil is frozen, and if it isn't, the burner doesn't come on. I could even send you all the parts if you want to cover shipping. The parts would be used, but in perfect working order.

that coolbot thing really does work if you have a compatible AC unit!

PJ, that's really funny, the link to State of Fanklin's in my home brew club and I visited Steve Jones' cooler (referenced) prior to building mine. He's a smart guy and very generous with his time and talents!

The only diff I see from the Ranco to the Coolbot might be a good one is the frost sensor. I'm thinking it would solve some problems and maybe not address others. Still, with the addition of an external fan (or rewiring the AC to stay constantly on). I guess I'd have to add an external thermometer to 'watch' the temp.

Here's a link to some pics of the set up and the soon-to-be famous Welcome Way Brewhouse. (The fan in front of the AC is now larger.)

http://picasaweb.google.com/nealperkins/Brewhouse082010?authkey=Gv1sRgCJ_K_vvvpP-6xAE&feat=email#

Spraying anything onto an evaporator coil is in my opinion not advisable. It creates more of an insulating effect on the coil and can create or increase the icing problem. You can add a small electric heating element to be energized on a timer basis to defrost the coil or you can simply put a defrost timer into the cycle. Shut the compressor off for a period of time while running a fan which blows air across the coil to defrost it. The defrost cycle should occur during known periods of time when entering the unit will not be happening.

If you are using this walk in as a fermentation chamber, there is always going to be moisture present in the space as the refridgeration process causes increased evaporation. The freeze ups you are seeing may be your product on the coil cross.

Salute!



Well now, I just viewed your pictures of the setup in question. You are using a window A/C unit (sorry I did not read all posts in this thread). You need to set the unit up for constant fan operation and disable the compressor for a period of time long enough to remove any build up. Many if not all window A/C units have a constant fan operation selection. Are you using some type of remote thermostat to control this unit? if so, just interrupt the compressor circuit, not the fan control. What temperature are you running this at?

Yes, the Ranco you saw drives the walk in.

For the fermentation chamber (separate unit) I did wire the unit up for the fan to run continuously (to keep the air moving against the conicals and carboys).

But, the walk in was built first and the wires are buried in walls. So, its really last gasp to do that. (I didn't figure I wanted to listen to the fan non-stop!) However, w/o a heat cycle somehow, the continuously running fan won't completely solve this either.

My offer still stands. I think it would remedy your problem pretty easily.

Here's a link to help with the wiring. Section 11-1 (page 51 of the pdf file) would be the schematic to reference. You may need to copy & paste the link. HBT goes through fyurl and it links it to some city profile forum. ???

https://secured.whirlpool.com/Servi...6f965983b38852574a5004bde8a/$FILE/8178743.pdf

Well . . .

"I'm no gynecologist, but I'll take a look at it."

So, I looked and it is not fairly easy to me. Hell, it looks like a road map to LA's freeways on steroids.

I'm thinking I should try a Coolbot, what with their guarantee and the very easy installation.

Thank you for your suggestions though!