Need A/C help

You need a new A/C tech......you need to change them when going to 410.

I'm in the situation right now, my tech doesn't see the need to replace the lines either. Quite frankly I hope that is accurate, replacing them would double labor costs and tear the boat open as I have an evaporator under the helm on the bridge.
Not a fun situation.

See post #69 from Capt. Ralph as well.

410 use a different oil and cannot get all of the oil out. 410 operates at a much higher pressure than r22 and generally utilizes larger lines than r22. Like I said before, you need a better A/C tech that isn't going to cut corners if you want the unit to last. If an A/C tech told me this, given the age of your boat, I'd throw him off of the boat immediately. Do you really think it's a wise idea to re-use 25 year old copper lines that have been in a salt environment, over again? Why ask the question if you're going to do it the wrong way anyways? Wasn't it this same A/C tech that recommended replacing the R 22 compressor that blew up in days?

Hmmm, got a quote yesterday to replace a 24k BTU split on my 48 Ocean Yachts SS which is 22 yrs young. Funky thing is one compressor is 24k but two 12k air handlers on the flybridge mounted side by side so 4 copper lines which, my tech whom I have used for many years says we only need to flush the lines for 410. I also heed advice from those who have more than one trip out the pass and back, probably need to discuss the issue more, $7600 just for the parts is not something I want to risk considering the old unit went 22 years. Anyone have a Taylor Dometic 24K BTU unit sitting on the shelf?

What do you think the lift expectancy of copper lines and their braised welds is when exposed to almost 400 psi of pressure and salt air? Willing to bet they'll go another 22 years for a total of 44, or just F'ing change the lines like you're supposed to? 410 operates at a lot higher pressure on the high side than R 22 (220 psi versus around 360 psi). Also 410 uses 1 size larger, copper line set than R22, so you're restricting your brand new unit right from the get go. Do you want your brand new unit to last?

Not changing the line set is like the guy that rebuilds the engine that blew up, but doesn't do the cooling system, turbo's, or injectors. These are the very same techs that say the new Dometic products are crap and fail early, when it's their installation that is crap.

Capt Ralph, I was hoping you would chime in. Not sure I am getting this correct, but two techs have informed me that I no longer have R22 in the system, is there a 471 or am I just getting my numbers back and it is really 417 in there now? The big problem I have is to replace the air handlers I will have to cut a largeish hole in the brow of my flybride but no one is giving me options to just replace the compressor side while the condensors are blowing strong. I realize is it best to replace everything and be done with it, just not a fan of cutting holes where some engineer never thought about replacement.

I am thinking I need to find another service tech to give his opinion. I have lurked quite some time and have read enough from Cpts J and Ralph to heed their advice when I ask for it. Thank you gentlemen.
Tim

I've skinned this cat several times.

1. R417 is about 20% less efficient than R22, that is true. I manage a yacht that had 6- R417 self contained units, temps out of the ducts were 56-58F of each unit. We dropped the 417 and put R 22, temps out of the ducts dropped to 44-46F out of every single unit, it made a big difference in the interior temperature of the yacht.

2. 410 is a lot more efficient. Overtime we've changed out 5 of those 6 self contained units. Not only do the new units have turbo blowers which move a lot more air, but the air temp out of the vents on each one is 34-36F now and we've dropped around 8 amps with all units running, which is a big deal as the boat only has a single 50 amp cord. Also interior temps in the helm area dropped noticeably when we were on it on a trip and had the temps set lower and half a dozen people...... 62' express.

All of these temps measured in the summer in South Florida with hot sea water and hot air temps. I also changed out 2 chillers on a 62' motor yacht and also noticed an amp drop...........and it seemed like the interior temps of boat did better on 1 chiller (home dock only had single 50 amp)

Compressor in the engine room is leaking freon, most likely at the fittings and at 22 years old I am not surprised. The air handlers blow strong and and the cooling fins look good where I can see them, but my ac guy has me sold on needing a new everything but the copper lines, which I am convinced now should be swapped as well "if" I am going to do this. I am not above finding another and attempting a patch job with new fittings and since, I think, we have 417 in the system already pump it up and see what happens. Here in the northern gulf quality marine ac techs are in short supply, not to mention the mess we are dealing with from hurricane Sally.

Capt Ralph or J, you by chance have a recommendation for someone you know, Panama City FL to Biloxi MS?

Me either, and in those days I was much younger.
Thank you again for your thoughts, i'll let you know how things work out, but I do think I will put total replacement on hold till I can do some trouble shooting.
Tim