Refrigeration startup and rehab

[sailah]

I bought my boat with an Adler/Barbour Cold Machine setup. Evap plate in a reasonably well insulated box. I believe the compressor is the BD35F, boat is currently dry docked undergoing repairs from an impact.

When we bought the boat, the surveyor noted the refrigeration system wasn't getting very cold, although it did get somewhat cold and the evaporator plate iced up a little. It was awhile ago so I'm going on memory.

I attempted to use it a few times and the compressor would just run and run without getting plate even remotely cold. So I said forget it and just used ice for the cruising we did as a family.

But it's been bothering me ever since and I do want to get it back up and running. I bought Richard Kollmans book and read it a few times. I've watched every YouTube video and tried to arm myself with as much knowledge as I can.

The evaporator plate looks to be in good condition, and the lineset as well. The only place I didn't like where the lineset was led is where it passes around a brace for one of the batteries. This leads me to the suspicion that somehow I may have a leak.

I have the following tools:

Manifold gauge set
Vacuum pump
Can tap
UV dye and flashlight
FLIR and Fluke temp measuring devices
Multimeter
Ultrasonic leak detector (Accutrak VPE)
Argon tank with regulator (welding gas I don't have nitrogen)
4 cans of DuPont Suva R134A

I'm a good listener and can follow instructions pretty well. I'll be getting the boat back next week and would like to understand this system and get it working.

Assuming teh system has been essentially unused for 4 years and had very weak cooling when it did work what would you recommend I do?

My plan is to do the following:

See if there is any pressure in system
If yes, well that changes things. If no, connect vacuum pump and let run for awhile to see how well it's holding vacuum. Can a regular gauge set do this or do I need some fancy micron gauge to test vacuum?
Let's say it doesn't hold vacuum. Purge with argon and use ultrasonic to see if I can pinpoint leak? I've been reading that UV dye is not good for these but how else am I supposed to pinpoint leak, soapy water? Obviously if I find the leak that will need to be addressed.

If a small amount of UV dye is fine to check, when do I introduce this to the system? I was thinking of adding some and then purging/pressurizing system with argon. That should get it to the leak yes?

After I rectify the leak, or maybe there isn't one (well how'd the charge get so low...) I was wondering the best way to meter the Suva back in after I vacuum it down again. 5 second blasts and wait 30 minutes to check frost on evap plate as Richard suggests? Small scale to weigh can?

Thanks for any suggestions or best practices, looking forward to this and subsequent improvements to thermostat and temp monitoring of ice box.

[Bleemus]

I will let the experts chime in but one thing I saw was that you dont have a recovery tank to put the gas in when you vacuum.

[sailah]

That part is true I don't have a recovery tank. My plan was to connect gauge set to see if there is indeed anything in the system. If I find that I do have something in the system, as I mentioned that will change things. Will probably call for a tech to recover what is in there and start fresh. I do like to do things myself, partly for economy, mainly for the knowledge.

My gut tells me that there isn't anything there. When I ran it for the first season we had it, the evap plate was luke cold at best. Subsequent runnings of it just to see if it would work it just diminished to where it would do absolutely nothing for hours for run time.

My suspicion is that where the PO ran the lines, it chafed against a wooden brace. I don't know if this is repairable or if I will have to buy a new evap plate. The compressor looks to be in perfect condition. It's in a very well ventilated area of the boat, no flashing LEDs, everything looks clean. My suspicion lies with the components/connections between compressor and evap plate. Although the plate looks to be unmarred I think it is also a candidate for a possible leak.

Maybe I'm completely wrong, but since this HVAC thing is outside my comfort level to diagnose that's why I want to understand before I start getting into it.

[sailah]

Originally Posted by Bleemus

I will let the experts chime in but one thing I saw was that you dont have a recovery tank to put the gas in when you vacuum.

Just so I'm clear you're saying if I find out I have R134A in the system I don't have a recovery tank to catch it? Correct, in which case I'll call a tech to perform that action for me.

I won't recover the argon if that's what you are referencing, just an inert gas.

[a64pilot]

A system as small as an AB cold machine that is low enough so that it doesn't cool pretty much doesn't have enough gas to recover.
That may offend many, but is the truth, the amount of gas left in it, is likely less than used to be in a spray can.
You know most all spray cans used freon back in the day as propellant, right?
Now millions or maybe billions of spray cans and all the industrial uses of "freon" was a huge amount, heck we used to wash Apache helicopters back in the day with CFC's, carbon tetrachloride I think, to keep the electronics dry, that was a large amount and I'm sure harmful.
Only leak detectors I have used detect refrigerant and if you had a big leak are good at finding it, tiny leaks only success I've had is with the dye and a UV light, need to use it in the dark, and have a strong light.

The fact that you intend to fix it and not just keep topping it up alone in my opinion makes you a good guy.

[Bleemus]

Wasnt trying to start a debate on CFC release into the atmosphere. Merely pointing out industry standards.

[Nightcrawler]

Sideways comment, replacing vs. repairing. If you find it over the top not to make sense repairing, take a look at Sea Frost. Cleave and his team helped me through replacing our cold plate system on Shangri-La last year. Frankly, easiest upgrade we've done so far. Excellent customer service. We're very happy with the result. We're keeping the fridge at 37 on 100+ days here in the Southeast.

[Bleemus]

The AC techs on YouTube pressurize with inert gas and spray soapy water on recent brazing and connections before charging system. You have what you need to do that.

[Matsubob]

If I were doing it, and if it is still cooling, I would first check all the fittings for tightness, then use the leak tester for obvious leaks. If there is nothing to speak of, I would add a little freon and see if it gets cold. It doesn't take a lot, and if the leak is slow, wait a while to look for the leak. It might even last a season or two!
Then if it shows that the leak is pretty big, do a visual on the lines to see if you can find any abrasions or likely places where the line has rubbed against something. Other places to look are at the weld joining the tubing to the plate; if it got bent when it was installed, there is nothing to help it, but the plate alone is available and doesn't cost as much as an entire system. Other culprits are the brass joints. If they weren't tightened properly, small amounts can leak from there. The simple remedy there is to just tighten everything, add R134A and wait to see if it is going to leak again.

[a64pilot]

Originally Posted by Bleemus

Wasnt trying to start a debate on CFC release into the atmosphere. Merely pointing out industry standards.

You were correct to do so to

[sailah]

Originally Posted by Nightcrawler

Sideways comment, replacing vs. repairing. If you find it over the top not to make sense repairing, take a look at Sea Frost. Cleave and his team helped me through replacing our cold plate system on Shangri-La last year. Frankly, easiest upgrade we've done so far. Excellent customer service. We're very happy with the result. We're keeping the fridge at 37 on 100+ days here in the Southeast.

Thanks, looking to fix vs replace. If I can't get it running I'll continue to use ice for the future.

Originally Posted by Bleemus

The AC techs on YouTube pressurize with inert gas and spray soapy water on recent brazing and connections before charging system. You have what you need to do that.

That was the thought. I don't have nitrogen but I do have a small pony bottle of Argon I use as a spare to my big TIG tank. Seems any inert gas is fine for purging or pressurizing a system. I've used soapy water countless times to check for leaks on other things, not sure if what I'm dealing with is so small it won't appear.

I don't have history of the system to go on like witnessing a degradation of performance or it was working fine last week and now it's not. I feel like I'm essentially starting from scratch and approaching it like I basically installed the system.

Hoping it's something simple and I gain a bit of working knowledge as payoff.

Originally Posted by Matsubob

If I were doing it, and if it is still cooling, I would first check all the fittings for tightness, then use the leak tester for obvious leaks. If there is nothing to speak of, I would add a little freon and see if it gets cold. It doesn't take a lot, and if the leak is slow, wait a while to look for the leak. It might even last a season or two!
Then if it shows that the leak is pretty big, do a visual on the lines to see if you can find any abrasions or likely places where the line has rubbed against something. Other places to look are at the weld joining the tubing to the plate; if it got bent when it was installed, there is nothing to help it, but the plate alone is available and doesn't cost as much as an entire system. Other culprits are the brass joints. If they weren't tightened properly, small amounts can leak from there. The simple remedy there is to just tighten everything, add R134A and wait to see if it is going to leak again.

I'm pretty sure the last time I ran the system last year it didn't cool at all. Like zero. I think it was when the boat was behind my house, on shore power getting ready for spring commissioning and I ran it for an hour to see if anything got cold.

I was of the impression that you don't want to just add R134A to a system unless you are sure it does not have moisture in it.

I have a couple suspect spots for the leak to be as I noted. Would like to confirm that they aren't leaking 100%. I think pressurizing and using argon would be a good way to do this without harm. Anyone savvy on what the pressure I should be using is? I think I may need to get a nitrogen regulator for my argon tank as mine is a flow meter for welding and not a pressure gauge. They use the same CGA580 tank connection.

I'm supposed to be back on the water in 2 weeks so I'll try and get these ideas tested and really look closely at the system

Thanks

[hellosailor]

Bubbles, UV, ultrasonic, all work if done appropriately. I think the key is to use every tool (leak tester) you have, patiently and repeatedly, because the leaks can be such damn clever things.

If there is a receiver/dryer in that system, that also needs to be replaced immediately before you refill the system. And of course if there are o-rings, those should be replaced (with the right type for that oil/gas) never re-used.

Technically, yes, you may be required to recover the R134a. But for the tiny amount in that system...I don't think it will impact your karma too much.

[Bleemus]

If I remember correctly NorCal, the YouTube AC/fridge, uses 50 psi for leak testing. I will try to track it down.

[Typhoon]

Originally Posted by sailah

Thanks, looking to fix vs replace. If I can't get it running I'll continue to use ice for the future.



That was the thought. I don't have nitrogen but I do have a small pony bottle of Argon I use as a spare to my big TIG tank. Seems any inert gas is fine for purging or pressurizing a system. I've used soapy water countless times to check for leaks on other things, not sure if what I'm dealing with is so small it won't appear.

I don't have history of the system to go on like witnessing a degradation of performance or it was working fine last week and now it's not. I feel like I'm essentially starting from scratch and approaching it like I basically installed the system.

Hoping it's something simple and I gain a bit of working knowledge as payoff.



I'm pretty sure the last time I ran the system last year it didn't cool at all. Like zero. I think it was when the boat was behind my house, on shore power getting ready for spring commissioning and I ran it for an hour to see if anything got cold.

I was of the impression that you don't want to just add R134A to a system unless you are sure it does not have moisture in it.

I have a couple suspect spots for the leak to be as I noted. Would like to confirm that they aren't leaking 100%. I think pressurizing and using argon would be a good way to do this without harm. Anyone savvy on what the pressure I should be using is? I think I may need to get a nitrogen regulator for my argon tank as mine is a flow meter for welding and not a pressure gauge. They use the same CGA580 tank connection.

I'm supposed to be back on the water in 2 weeks so I'll try and get these ideas tested and really look closely at the system

Thanks

Argon has larger molecules then Nitrogen so not quite as good for checking for leaks . , be careful with those pressures. We test to 200 PSI and let sit over night .

This is a good read

https://www.epa.gov/sites/production...eakTesting.pdf

Regards John.

[Maka]

I have the same unit that only cools to 50 degrees.
Cant wait to hear what the final solution is for you.