CoolBlue - is it worth the extra $$$

[kmacdonald]

I guess if you don't mind setting your freezer well above 0 degrees you could get by with a holding plate system. Not something I would do but YMMV. When comparing lets stick with 0 degrees for both system to do an apples to apples comparison.

[newhaul]

Using the cool blue system here with a single holding plate using an average of 30 to 35 ah daily with a 7 cf refer and a 2.5 cf freezer . Maintain -5°f in freezer and 38°f in reefer. Yes its not the tropics and I expect to jump to about 50 ah when in the tropics.

An aside Google it there are several holding plate'sysetme'out there . Most people'dont use them I assume due to the almost double initial cost. I have installed holding plate systems and evaporation plate systems . Don't hear any complaints about holding plates but have heard some about the evaporation systems not doing a good enough job.

[SV THIRD DAY]

Originally Posted by missourisailor

The problem that I have with his test is that he has changed TWO variables.
ONE - Holding plaste vs thin plate
TWO - orifice vs expansion valve.

I'm wondering if most of the reduced Ah's is not because of the holding plate but has more to do with the use of an expansion valve?

Bingo...
The two variables often confuse people.
The holding plate gets you a few benefits:
The ability to "store cold" inside your box to have a dramatically difference on the compressor cycle times. Take a look at this graph, below from a Box test. The compressor running a holding plate system turns on/off 4 time in a 24hr period, while the compressor running a thin rolled aluminum evaporation plate turned on/off over 150 times in that same 24hr period. Same box, same test conditions and a lot less wear and tear and start-up wasted amp draw as the compressor doing nothing until it builds up pressures. Now if you don't think cycling your compressor 4 times in 24hr is better than +150 times then, hey...that's your call. You don't think there is a coincidence that we are the only company to offer a 5hr warranty and this difference in compressor (and electronic control box) cycling do you....

Image No 1 CoolBlue Temps/Compressor Cycle Profile:

Image No 2 Thin Rolled Aluminum Temps/Compressor Cycle


Now Mr Kollmann says:
"When water or solution of liquids are phase changed to a solid form by freezing it then becomes an insulator reducing its effect as an efficient evaporator." But is that true...well maybe it is on the Holding plate systems he has build and has experience with, but CoolBlue is the only holding plate manufacturer that doesn't just put a coil of copper tubes inside their holding plates or this statement would be true. But inside of our holding plates is this photo below. A massive aluminum fin/tube condenser. The surfaces area is massive and it allows for a very efficient heat transfer between the eutectic solution and the refrigerant gas.

Image No 3 Fin/Tube Holding Plate


Now back to the Critical Orifice vs the Thermally adjusting expansion valve. That is where a big portion of the increased efficiency comes from. As I discussed in detail in an above post, this lets the refrigeration volume go from around 4-5oz up to 24oz letting us increase our condenser and take out more heat. But it is also a much more efficient way to run the evaporator.

So our increased efficiency is a combination of the two system differences.

Now, why are not more people making holding plate systems?
That's easy...the COST.
But there are other manufacturers: SeaFrost, Isotherm and OzeFridge.
Holding plate systems simply cost more to build in parts and labor, and that translates into an increased sales price. Sure we could be like everyone else and go for the bottom dollar and have an evaporation thin rolled system stamped out in China and our net cost of production would go down 3X. So if Cost is your main driver, there are plenty of low cost systems out there on the market for you. But that is not our nitch. Since 1968 (longer than any other marine refrigeration company by the way...that ain't an accident) we have targeted the efficiency/quality build segment of the cruising market. You pay more upfront but save power on the back end along with the simple fact that there is not another manufacturer that gives a warranty and customer service like we do. Try to talk to and ask questions and get 7 day a week customer service from the owner of the other made in China/Corporate brands and see how that goes....good luck.

[missourisailor]

Originally Posted by a64pilot

You compare a system to a system, not pieces parts to pieces parts or it doesn't tell much.

I totally agree!!!!
Mr. Boren's system is engineered to maximize the efficiency of holding plate system. And the current draw that others have shown, proves it.

I was just wondering if a flat plat evaporator, that uses an expansion valve, would equal or beat the holding plate.

My CoolBlue system is smaller than yours (one evaporator and a Danfoss 35), but is consuming MORE Ah's than yours. And from what I have read, my system has more insulation than your.

[SV THIRD DAY]

Originally Posted by kmacdonald

I guess if you don't mind setting your freezer well above 0 degrees you could get by with a holding plate system. Not something I would do but YMMV. When comparing lets stick with 0 degrees for both system to do an apples to apples comparison.

Not sure why the false assumption that a Holding Plate system can't get to 0-degs...mine's running there now along with plenty of our clients cruising the seven seas. Could be be another cruising myth?

[SV THIRD DAY]

Originally Posted by missourisailor

I was just wondering if a flat plat evaporator, that uses an expansion valve, would equal or beat the holding plate.

A flat evaporation plate using a TXV will use less power than a system with a critical orifice...BUT it will still not be as efficient as a holding plate. Why...compressor cycles...remember the data presented above, it costs power to cycle the compressor 150+ per day versus single digit cycling with a holding plate system.

I helped Typhoon build such a system in another thread, so check that one out for details.

[missourisailor]

Originally Posted by SV THIRD DAY

Now if you don't think cycling your compressor 4 times in 24hr is better than +150 times then, hey...that's your call. You don't think there is a coincidence that we are the only company to offer a 5hr warranty and this difference in compressor (and electronic control box) cycling do you....

Total agreement!!!
But mine runs for about 18 to 20 hours before shutting off. And this is after a few cycles.
Which can't/isn't good for it either.

And this is with a box full of frozen stuff, factory insulation on the outside and two inches of insulation added to the inside. 2/3 : 1/3 Fridge:Freezer ratio. Box size most likley a tad bit smaller than A64's, as we have about the same boat.

I'm just wondering if a properly designed plate system with a TXV would be better. For my box at least.

[a64pilot]

Originally Posted by missourisailor

I totally agree!!!!
Mr. Boren's system is engineered to maximize the efficiency of holding plate system. And the current draw that others have shown, proves it.

I was just wondering if a flat plat evaporator, that uses an expansion valve, would equal or beat the holding plate.

My CoolBlue system is smaller than yours (one evaporator and a Danfoss 35), but is consuming MORE Ah's than yours. And from what I have read, my system has more insulation than your.

Your using more than 100 AH a day? I am. How much more, I really don't know, I don't want to I think, cause if i did, I'd have to fix it
Now understand when I first started talking with Rich, he pretty much immediately said I needed to upgrade / replace my insulation, truth is it wasn't all that good to begin with and didn't get better with 30 yrs of age.
But I'm Hard Headed, I didn't want to tackle tearing the whole thing out and rebuilding it, which is really the best fix, but more work than I wanted at that point as I had several other large projects going and I only have weekends to do them.
I told him I know a sledge hammer is not the best way to kill flies, but you can in fact kill them with a sledge hammer, will or can you build me a sledge hammer that will keep ice cream and beer cold in a 14 cu ft box with thin, 30 yr old insulation? I accept it won't be efficient, you build it, I will figure out a way to power the thing, so he built it, it works and is less efficient than it would be with decent insulation.
I do plan on adding insulation, as it is the box is just too big, especially too deep. Wife has to stand on a stool to reach the bottom, and if its in the back I have to get it. I think the idea was to put a foot of ice on the bottom as it was an ice box, raise the bottom with ice and it's not too deep, But I plan on 6" of insulation on the bottom and three on the sides and top, eventually.

[SV THIRD DAY]

Originally Posted by missourisailor

Total agreement!!!
But mine runs for about 18 to 20 hours before shutting off. And this is after a few cycles.
Which can't/isn't good for it either.

And this is with a box full of frozen stuff, factory insulation on the outside and two inches of insulation added to the inside. 2/3 : 1/3 Fridge:Freezer ratio. Box size most likley a tad bit smaller than A64's, as we have about the same boat.

I'm just wondering if a properly designed plate system with a TXV would be better. For my box at least.

To know exactly we need to know your Cubic Foot Volume because cause there is such a thing as Too Large a Box and too little insulation for the System. If your unit is running 18 to 20hrs per day you either have:
1. A system low on charge which causes the compressor to run excessively without hitting the low end cut-off temp.
2. You have bad insulation and a low R-value so that the amount of heat coming into the Box is excessive and does not allow the unit to cycle off.
3. Based on your box volume you do not have enough holding plate area/volume and are simply asking too much of the system.
4. A Box volume that when combined with your R-value is just too large for the CoolBlue to handle.

Why haven't you called me before.....Amigo...that's why I'm here 7 days a week to help. Phone 619-609-3432.

[missourisailor]

Originally Posted by a64pilot

Your using more than 100 AH a day?

5~6 amp draw x 20 hours is how much.

[a64pilot]

Missourisailor,
Mine runs depending on outside temp almost continuously in tropics when we are opening it several times an hour and I believe when motoring as the engine shares a wall with my freezer, it never shuts off.

But I think these little compressors will run a very, very long time. I got rid of my house side by side Kenmore fridge after 20+ yrs not because it didn't cool well,but because the outside was beginning to rust and the handles had worn so it looked bad, it was just an eye sore. I knew it had to go when my Son nicknamed it "Rusty" it did just as well as it did new, and I keep the fridge right at where milk freezes and when you take a bottle of beer out it forms frost on the outside, so I work them hard.

[SV THIRD DAY]

Originally Posted by a64pilot

But I think these little compressors will run a very, very long time. .

We are talking about a 200,000 hour compressor....that's a long time indeed. Longer than most people will own their boats. That's 22yrs of running around the clock. What other piece of equipment on the boat can even come close to that?

[missourisailor]

Originally Posted by SV THIRD DAY

Why haven't you called me before.....Amigo...that's why I'm here 7 days a week to help. Phone 619-609-3432.

We've talked several times.
I'm the one whom bought two of your digital stats. And most recent conversation, think I have either a bad or maladjusted expansion valve.

I'm basically an absentee owner and only get to the boat once every two months or so.
So I have not been back to the boat since we last spoke. And have not gotten any new data for you yet.

[SV THIRD DAY]

Got it...I can't relate the Forum name to the client name.
But keep me updated and when you get back to the boat give me a call and we can talk about adjusting the expansion valve. To do that you will need to have a charge hose with a low pressure gauge on it.

[ErikFinn]

Thank you very much for your lengthy reply Mr. Boren, Rich, much appreciated and always a pleasure to learn more. And I do like your system. I should have replied earlier but.. Anyways, something I think I discovered unless I'm mistaken:
I understand one performance factor to take into account when comparing compressor performances is the displacement:
Secop BD35F: 2.00 cm3
Secop BD50F: 2.50 cm3
Secop BD80F: 3.00 cm3
Cubigel GD30FDC: 3.00 cm3

Of course there are other factors as well but would it be fair to say that the current CoolBlue compressor (Cubigel GD30FDC) is more in par with the Secop BD80F than the BD50F in terms of BTU output potential?

I think I earlier got the idea that the GD30FSC was similar to BD35F as the earlier CoolBlues used the BD35F?

Thanks,

Erik