Refrigeration Replacement

[Typhoon]

There is a lot more to this discussion . And it is a long read . I will start writing a blog post with all the science and graphs . Then when people ask me why I use an expansion valve and why my systems are so expensive I can just direct them to my white paper .

Regards John
www.coldeh.com

[a64pilot]

Understand, if you can control the variables a cap tube system can be very efficient and trouble free.
Cost of manufacturing is less too.
I’d bet without looking that many if not most of the ice box coolers are cap tube systems, I think most of not all house fridges are? Not sure on house fridges cause to be honest I have never had to work on them beyond changing thermostats and ice makers etc.

Now just me, but any system I’d want would also have service ports. I don’t want to have to solder in any, plus I’d like one that is flexible enough in its refrigerant capacity that I could just drain it down to atmospheric pressure or just slightly higher and service with X amount of refrigerant. I don’t want to have to measure weight precisely, or watch for frost lines, adding in 2 sec bursts of refrigerant over a long period to get it right.
You can’t do that with a cap tube, those are very sensitive to amount fo refrigerant.
On edit, I also want a receiver / drier. A receiver drier is to some extent an accumulator, it has the ability to hold excess refrigerant when it’s not needed, it also will absorb some moisture which turns into acid if it’s left there, it is also a filter to some extent and may filter particles that could clog an expansion valve.

[Typhoon]

Yes , almost all coolers and home fridges are built using Captube technology. Most industrial roof top air-conditioners, walk in freezers are all TXV . Seems a lot of the industry is moving toward TXV systems . Every body nowadays what to conserve power

https://assets.danfoss.com/documents...1786418990.pdf

In a boat with ever changing ambient temperatures is a no brainer !!



TXV systems are charged using site glasses and they are not critically charge.

High and low ports are standard.

https://www.youtube.com/watch?v=ACaS7Cavt-k

Regards John
www.coldeh.com

[RaymondR]

Over in another place on the site we had a pissing contest between John and Pete regarding the comparative utilities of cold plate versus eutectic systems - apparently both are refrigeration specialists. After battering each other about for a few days they kissed and made up and the thread has gone a bit quiet.

Before I go any further I want to express my appreciation for their efforts. As a lay person, in refrigeration terms, I only became exposed to refrigeration technicalities when I began the struggle to keep food and beer cold whilst living on a boat but, in that boat refrigeration is coupled with an off-grid aspects of the problem, I have found it to be a fascinating subject. It's like exploring the personality of a new partner without the angst of the eventual breakup. Thank you John and Pete for your contribution to my body of knowledge re boat refrigeration.

To summarize the positions of the protagonists:

John is a cold plate and TVX valve man. Pete a capillary tube and eutectic tank proponent.

John feels that a TVX valve is required in order to meet the energy use and highly varying refrigeration load of a boat refrigeration installation.

Pete believes that by exploiting the fly-wheel effect of eutectic systems he can optimize and match capillary and compressor size to enable just as efficient a compressing/condensing/evaporating system as John's TVX valved copper cold plate system.

Both are getting in some pretty good licks and the rest of us are being exposed to a lot of good information and being obliged to ponder on issues we were not previously aware of the existence of. Keep up the good work men.

[SV THIRD DAY]

Then there is the CoolBlue system by Technautics that is a cross between John's and Pete's. It's a Eutectic Holding plate that uses a TXV. After 50yrs in the marine refrigeration biz, when I see these "who's is better" threads, I just move on most of the time because after the 100th time of talking about the SAME TOPIC over and over....honestly....I'm living in Mexico and have Taco Carts to visit. So I let the enthusiasm be taken up by the new guys on the block who don't have units in the field yet with longer lives than our standard warranty. That's not a knock...it's just that I've learned I don't have to be the Best in Everyone's Mind...just the Best in the minds of our clients.

The truth is all three of these systems are good and the daily Amp Hour differences are minor between them (GASP....how can you say the Truth out loud), but that doesn't mean the parties won't bicker about who's is better, that's just what tecky geeks do for entertainment. All three of these systems are far better than the units I am constantly removing from boats here in Mexico and replacing them with units made for the Tropics. Real life cruising is the ultimate data test set and Cold Beer and Hard Ice Cream at anchor is your reward.