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Hey Wowza,

If you don`t want to scramble the compressor, you need to be careful about letting the frostback get past the accumulator and into the compressor. That`s the job for the accumulator (that little black expanded bulb in the suction line returning to the compressor). Running that compressor with no heat load on it, ie without heat transfer of the water, is extremely hard on it. It would only take a half dozen or so times of your name written in frost to knock out the compressor. Also, do NOT remove any fins from the condenser; I gave that advice in an earlier thread about the evaporator that another guy was going to immerse in his reservoir. I see you removed the fan blade that was going to the evaporator; good move, `will cut down on the air noise. You`re on the right track. You can get some Armaflex (brand) sheet closed cell rubber insulation at most refrigeration supply houses. Even though these places are wholesale, I think they will still sell this to you, as that would be no threat to the tradesmen competition wise. `Same goes for the Armaflex pipe insulation, which comes in varying thicknesses and I.D.s. If you`re going to run your refrigerant piping any distance over 20 feet, you need to vapor seal each joint of pipe insulation. Black duct tape will be good enough, unless you want to use spray on contact glue. A better evaporator to immerse in the water was shown in the earlier thread, which consisted of a specially coiled copper tube specifically made for this type of setup. But to do this you need to be prepared to do some refrigeration work, which would take the right tools and materials (freon-22, refrigerant scale, torch, vacuum pump, copper couplings,refrigerant access taps w./schrader valves, 15% silv-floss, and the skills and know to use them). If you have any more questions relating to this topic, ie refrigeration and chillers, let 38 years of experience give you a hand.
 

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Hey Wowza,

Why not set that chiller outside and make it a split system. What I`m talking about is setting the compressor/condenser unit outside and pipe the refrigerant lines through a wall/window to the evaporator inside your house where it sits in the reservoir. The only other control you`ll need for the outside unit is a condenser fan cycling control for cold weather operation. This control would connect to the refrigerant liquid line (smaller refrigerant line to the evaporator) via of an access tee with a schrader tap. This control would keep the refrigerant pressures at the correct level for proper operation when it`s cold outside. When the weather warms up it would just keep the fan run normally, instead of cycling on and off. You just have to make sure that you have the glycol mix concentrated enough for winter time, in case the pump quit or got shut off accidentally.
 

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You don`t need to insulate the compressor itself, just the suction line and accumulator connecting to the compressor. The compressor shouldn`t get cold enough during normal operation to cause condensation. If something weird happens to cause it to get cold enough to have condensation form on it, then there is some improper operating condition. If this is worrying you, then you can cover the area where the suction line enters (maybe a 2" to 3" diameter area) it with closed cell rubber insulation (Armaflex). You have to be careful here, so as not to cover too much area. If you do, it could cause the compressor to run too hot and also present a fire hazard with the insulation getting too warm.
 

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Hi Wowza,

`Been checking your build progress and noticed that you`re using a slim cooler. Looking down inside it, you may not have enough water volume in it to allow your 5100 BTU unit to run long enough between cycles. If it short cycles that will be hard on your compressor. Since you got this far into your build, your best option is to move enough water to maybe offset the above condition. Will your pump move 2 gpm with the restriction of the your water block? Also, try to discharge the warmest water into the bottom of the cooler, and draw the returned cooler water from a level about half way up from the top of the cooler tank. If you have more flow that you need (lol), you can put a balancing valve on the leaving side of the pump. This type of valve restricts flow in such a way so as not to create turbulence in the flow. `Chances are that you won`t need one, and only if your pump delivers way too much flow. Just remember that this unit is a chiller, and not something capable of temps. much below freezing. I wouldn`t run the water temp. below 25 F. You won`t need too concentrated a glycol mix for that, which will be better for heat transfer and easier on your pump. Anything colder that this setup would be comparable with a phase change unit.
 

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Hey Wowza,

I noticed the green windshield wash in the pic. Here in Oklahoma the Wal-Mart in my hometown has three colors of windshield wash; red, blue and green. Maybe they have it where you live?
 

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Hi Wowza,

I do have all of those tools, etc., but I`m not ready to oc just yet; maybe not at all. I just have too many other things going on to get that involved with oc. I like to help people when I can, though. Actually, I haven`t been involved too much with cascade systems in all my years in the business. Truthfully, I worked on only 3 cascade systems, and they were in labs and already set up. Plus, those systems didn`t have to deal with the types of problems you guys have to figure out. So, in this regard it will be a learning experience for me too.
 
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