HVAC Replacement Guidance

[Hat52MY]

On this last trip we had a 24K BTU scroll compressor give up its life in the engine room. This is a Split System. It has been suggested, I have 3 options at this time given the existing system utilizes R22 Blend refrigerant.

1) Replace with a NEW MarineAire/Dometic 24K BTU system, that would require replacing both the Evaporating Unit and Compressor Unit to allow for the 410 Refrigerant. If they are able to locate a unit, shipping/delivery is several months out (China parts & US assembled). Cost 3x

2) Replace with an off brand (CTM?) 24K BTU unit. This would also, require replacing both the Evaporating Unit and Compressor Unit to allow for the 410 Refrigerant. Availability is better than MarineAire but still supply channel constrained (China parts & China assembly). Cost 2x

3) Retrofit with a new 24BTU Copeland Compressor, Reversing Valve, Dryer, accumulator, valves, Capacitor’s, etc…essentially like new and will utilize R22 and no need to replace the Evaporating Unit. Parts are available to have job complete in the next few weeks. Cost 1x

I’m not particularly a fan of options 1 & 2 but was interested in other’s thoughts:
- R410 is due to be discontinued in 2025
- R410 system out of sync with 4 other existing R22 Systems in good working condition.
- Require different set of emergency spares (controls, PCB boards, capacitors, refrigerant, etc)
- Availably is still questionable (supply chain and chips) and may not be completed until Fall/Winter
- Cost 3x to 2x more and not much benefit

Forward Thinking:
- How are new systems being designed past 2025?
- Past 2025, what would be a good redesign of an existing 5 HVAC split units (3x 24K BTU & 2x 12K BTU)? Would this best be done with self contained units? One or Two Chillers with 5 Air Handlers?

Appreciate the insights!

 

[rwaldrop13]

Based on my experience i would go with any company BUT MarineAire. I had a unit arrive dead out of the box, they wanted me to pay for replacement part, unit pump control relay shorted out within first 3 months and their response was to void my warranty "because it's always the customer's fault".

 

[zigzag930]

My $.02

I'd pressure test the evaporator and line set, then replace the compressor with R22 if you have access to one. This keeps the whole boat R22 providing some parts redundancy.

With 410 going away, not sure it makes a lot of sense to go that route. My understanding is that the new refrigerants will be flammable, ie containing propane, butane, etc. The last drink cooler I installed on our LRC has butane as a refrigerant. I looked and as of a few months ago I couldn't even find that refrigerant available anywhere in the US.

I didn't realize this unit was butane based refrigerant but fortunately, the unit is outside in my covered aft deck. I wouldn't want to have a flammable refrigerant down below or in my ER.

I have old MarineAir systems (5 of them) and they are all still running well. Not sure the new ones would last anywhere near as long. I do have a minuet leak on one system that I haven't attempted to track down yet. I have to add 1/2 lb of R22 once a year so not the end of the world.

 

[cww]

The choice would be clear to me, just replace the dead compressor by having an ac shop braze in the direct-fit replacement that's available from grainger and call it a day. No need to reinvent the wheel / gamble on something with a bunch of extra electronics that won't last for 30 years like the one you already have.

 

[Pascal]

I would just replace the compressor assuming the rest of the system is good (evap, coil etc)

Costs of new units are getting ridiculous while the quality is going down. A neighbor of mine was just quoted almost $4k for a new 18k btu self contained…

I love my chiller system (two 36k chiller and 5 AH) but it s a big and expensive project. 4 or 5 years ago, I paid about $25k for all the hardware plus a week of my time to install. I guess nowadays it would be about $30/35k plus install.

 

[ageless]

I would just replace the compressor assuming the rest of the system is good (evap, coil etc)Costs of new units are getting ridiculous while the quality is going down. A neighbor of mine was just quoted almost $4k for a new 18k btu self contained…I love my chiller system (two 36k chiller and 5 AH) but it s a big and expensive project. 4 or 5 years ago, I paid about $25k for all the hardware plus a week of my time to install. I guess nowadays it would be about $30/35k plus install.

$55k installed in a 55c from flagship, quoted last week.

 

[Pascal]

$55k installed in a 55c from flagship, quoted last week.

Glad I did it when I did!!! I should have mentioned that in my case installation was easier as I had the VIP and master gutted combining them at the time and in the 53MY, it is short hose run from the ER up to the salon and galley.

 

[rustybucket]

I'd acid test the refrigerant to see what I was dealing with. Then evac and properly clean/flush (if necessary) and throw a new compressor in it and recharge with same refrigerant.
While the unit was out I'd probably go ahead and replace the service valves and accumulator. The service valves can be quite leaky as they age.

 

[JD5652]

I'd go with Option 3... and actually there is a fourth option which I just did in February as I was in the same boat....

R417 compressors are compatible with R22. Had my HVAC guy buy a Cruisair R417 compressor.. evacuate and clean it.... install it and charge it with R22.

 

[Hat52MY]

Appreciate everyone’s input…. Replacing the existing compressor seems to be the way go. Will also ask about potentially replacing with a 417 compress/conversion to R22, assuming there is no supply chain snarls.

Thank you all!

 

[dsharp]

Is it possible to use the R22 replacement refrigerants?

 

[cww]

Is it possible to use the R22 replacement refrigerants?

Why? Get a jug of R22 off ebay for $300 and you'll be set for the next 10 years. These systems don't hold that much compared to a house a/c.

 

[Eddieclemons]

Why? Get a jug of R22 off ebay for $300 and you'll be set for the next 10 years. These systems don't hold that much compared to a house a/c.

I researched the same subject about a year ago and was given some good advice here to buy r22 and run with it. I did and it's been great for a year after adding a little to 2 of my 4 units. My slip neighbor upgraded to newer refrigerant and his temperatures are not near as efficient heating or cooling than the old R22.

 

[52CMY]

Hate to sound like the "Green Guy" on a classic Hatteras site but I will say some of the new high efficiency variable speed conventional split unit, self contained, or Chiller units are getting very attractive as prices come down and technology improves. By throttling unit BTU output based on demand, power consumption and efficiency gets to the point that you can keep big boat cool overnight using just a (BIG) LiFePro battery bank, with the GenSet OFF at anchor, or at pierside without shorepower or vastly reduced shorepower requirements.

I hate my noisy Onan 20KW genSet and love when it's not needed.

All my HVAC maintenance & upgrade decisions will be with an eye to eventual upgrade to variable compressor chillers. I have no connection to this outfit in Boston called BoatRX other than occasional internet comms but he has some good videos discussing high efficiency Battery AC upgrades:

https://youtu.be/fmSeCAnQ5Rk
https://youtu.be/YLSP_X24h_0

 

[scottinsydney]

Been following this thread closely.....

The 120v compressor has seized on the original twin room R22 7000 BTU Cruisair.

R22 is now banned in Australia and cannot be sold. R22 systems are being refilled with "compatible" R438A." Two of the aircons on my boat are already filled with R438A.

I have looked at options including having a new identical condenser made in Florida, swapping to a Webasto all in one aircon, or having a replacement 120v compressor soldered in. Each option has advantages and disadvantages here in Oz. There are no small 120v compressors available in Australia.

My Question: I've looked at the Grainger catalogue.... but am still wondering what would be the correct replacement compressor part number? Could anyone suggest the Grainger part number please.

 

[whoover]

I also would like to just replace a tired r22 compressor and finding a new compatible replacement would be the best way to repair it.

Walt Hoover

 

[cww]

Been following this thread closely.....

The 120v compressor has seized on the original twin room R22 7000 BTU Cruisair.

R22 is now banned in Australia and cannot be sold. R22 systems are being refilled with "compatible" R438A." Two of the aircons on my boat are already filled with R438A.

I have looked at options including having a new identical condenser made in Florida, swapping to a Webasto all in one aircon, or having a replacement 120v compressor soldered in. Each option has advantages and disadvantages here in Oz. There are no small 120v compressors available in Australia.

My Question: I've looked at the Grainger catalogue.... but am still wondering what would be the correct replacement compressor part number? Could anyone suggest the Grainger part number please.

View attachment 60834

Is it "banned" like R12 in the U.S. where China still makes it and you can buy it online labeled as 'recycled' refrigerant or are they legit taking it seriously down there? I don't mean to sound like a prick, I really do care about the environment, just not enough to want to sweat all summer in Florida. The basic physics dictate that the older refrigerants have higher thermal efficiency, so unless you also swap out the compressor body for a new one with more real estate on the water cooling coils, changing to a new refrigerant is never going to work as well. People will tell you all you have to do is flush it and change the oil and orifice over to one for the new gas, but it'll just never be as cold.

Owning classic cars and living in FL you become an unintentional "expurt" in this. If you just want it to work, propane is an environmentally friendly direct drop-in replacement for R12 and R22 and is compatible with the mineral refrigerant oil that'll be in there. I've used that with great success in cars, but whether you want it on your boat is possible another story. In a car a few ounces of propane is the least of your worries in a fire vs. the 20 gallons of gasoline you're already carrying around anyway, so the risk profile is different.

There's another thread I printed out and saved, where the exact model number of the replacement compressors are listed from grainger. Do a search for "grainger" and it should come up.

 

[cww]

Here, I'm pretty sure this (or one of its immediate brothers or sisters) is what you want.

AKA5512EXA (tecumseh.com)​

 

[cww]

And here it is for $300-something

Tecumseh AKA5512EXA - Hermetic Reciprocating Compressor (coldaircentral.com)

 

[scottinsydney]

Thanks for the reply.

I looked at the compressor which is 12000BTU... I presume this means it works for aircons UP TO 12000BTU????