A/C Compressor question

I am in no way a service tech for AC systems, I have on many occasions studied service/repair manuals in order to better understand what and why something is the way it is and if professionals need to be brought in.

One beautiful thing about the internet today, almost any product has an online pdf download that can be looked at. It could be that there is a reason for split temperatures, you can find out if so and what readings should be shown.

A little study of the system might save some big bucks just by knowing what might be the problem. I have had many suggestions to change expensive parts over the years, when in fact the repair would be completely wrong for the problem.

Just my .02

I looked again and realize the two units are separate and if the same model, should show like readings with only a small difference (if any) between them.
Still.....do the study

Marmot, your key words are: An R22 unit can be fixed as long as an owner is willing to pay for it.

Yes and no. Yes, you still can repair R22 systems, and yes you still can get R22 refrigerant. However, try finding some of the R22 parts for many different types of systems can be difficult and not worth the cost. You cannot find a new Marine Air, air handler for R22 in the US even though you might have changed the condensor unit 2 years ago, you can find the pieces for the air handler yes, but if you add up all of the pieces such as blower motor, coils,etc. the cost is astronomical compared to if you could've bought the entire air handler assembly for $1200 etc etc.....

For example, if you have a household TRANE 2 ton a/c unit and the air handler goes bad, you are not going to find a new TRANE 2 ton air handler to replace it, thus having to replace the air handler and condensor unit with an R410 unit. Sure you could piece it, and put new R22 coils in the old air handler, but by the time you figure in labor and the age of other parts, it's not too much more to replace the entire unit. Not to mention the cost of R22 has tripled in the last year or so, it was $130/30lbs, now it is over $400/30lbs and will keep increasing just like R12 did and went up to over $1000/30lbs. When I was a kid, I remember going into the local auto parts store and they had the 1lb cans or R12 stacked up almost to the ceiling like a pyramid and they were on sale for $0.69 a can.

If you don't know the rules or what you need or what you are looking at you (or the owner) will get screwed.

I am not trying to say that it is not worth changing a crapped out old unit to the latest and most efficient and easily maintainable technology, I am saying that it is very possible to renew the components of an R-22 system and do it economically. If the refrigerant is not lost because of a major leak, it can be recovered and reused in the repaired system. If it was lost, recycled refrigerant is available even though the price is becoming high.

Which alternative is the best depends on the specific installation, boat operating parameters, area of operation, and crew skills.

Bluntly stating that even the most simple system failure requires complete system replacement is ignorant and creates the type of unnecessary expense that leads owners to find places to spend their time and money other than continually dumping it down the yacht machinery drain because they rely on bad advice from people who shouldn't be giving it.

About 5 minutes on Google returned the following links and there are thousands more sources since R-22 is used throughout the world and somewhere between 55 and 90 million pounds will be imported into the US in 2012.

R22 compressor:

A/C Compressor, R22 - Air Conditioner Compressors - Air Conditioners - 6D644 : Grainger Industrial Supply

R22 condensers for home use:
Heat Pumps | Air Conditioners | Gas Furnaces | Wholesale - R-22 Condensers

Complete water cooled condenser units:
http://www.heatcraftrpd.com/Products/PDF\Bohn Tech Bulletins Folder\BN-TB-CU-WATERCOOLED-.5-6.pdf

R22 evaporator/air handlers per the 2012 Dometic price list. Look at page 8:
DASH AIR - Low Profile Evaporators (R417A/R22) for 2012_Marine-ac.com_Official_Dometic_Marine_Air_Price_Book

Here's the problem with fixing an R-22 unit, or buying a 2010 or newer R22 unit. (If the repair is $750 or under on a pre-2010 unit, I would repair an r-22 system, but over that it's not worth it in the long run, unfortunately. SEE 2015 CHANGES, units produced after 2010 will not be allowed to be recharged legally. Try finding a reputable a/c contracter that is willing to lose their license over 1 yacht owner. 2015 is 2 1/2 years away!

Changes for 2010
■Production and distribution of HCFC-22 and HCFC-142b freon will be limited by regulating manufacturers. Some manufacturers will be required to stop production.
■Approved manufactures will be exempt from some or all of the regulating standards.
■Existing HCFC-22 and HCFC-142b freon can still be reclaimed to be recycled for reuse.
■All newly manufactured HVAC equipment must function without HCFC-22 and HCFC-142b freon. New HVAC equipment will be required to use refrigerant approved by the EPA.
■75% of freon will be phased out of the United States by limiting consumption and new production.

Scheduled Changes for 2015
■Regulating standards will apply to all manufacturers, distributors, and consumers. No exemptions will exist.
■Only HVAC equipment manufactured before January 1, 2010 will be recharged with HCFC-22 and HCFC-142b freon.

Scheduled Changes for 2020
■All manufacturing and production of HCFC will be banned. No demand for freon will be met by production of new freon, even for equipment purchased prior to 2010.

AS FOR PURCHASING ONE OF THOSE NITROGEN FILLED HOUSEHOLD COMPRESSORS

■As of January 1, 2010 it is illegal to charge any residential hvac equipment manufactured after January 1, 2010 with R-22 freon. Units manufactured before that date can still be charged with R-22 if serviceable. If unserviceable, they may be replaced from the manufacturers existing inventory of unused/unsold units if available, of R22 refrigerant units manufactured before January 1, 2010 or the newer units manufactured after January 1, 2010 which utilize R410a freon. Units manufactured after January 1, 2010 for residential use may only be charged with R410a freon if a leak occurs.

Current Freon Law | R-22 Phase out | R-410A | R-410A A/C Equipment

You must sell new refrigeration equipment or something, methinks you protest too much.

The solution to what you see as "the problem" is - who cares? R-417 is a "drop in" replacement for R-22 and the new equipment will function quite well with either one. You can continue to run with 22 until it is impossible to obtain then switch to 417. And, who knows, considering the installed base of R-22 systems, an even better drop-in may show up before the door is completely closed.

A new component installed today should least far longer than 2 1/2 years and reclaimed 22 will be available for the projected life of the equipment. Find something else to worry about.

Yeah? Show me one who arrives on a boat with a recovery machine and recovery bottle. Show me a boat that even keeps an ODS log.

The real point of this discussion is that contrary to what the resident pretender might claim, the sky has not fallen. It is possible and even economical to maintain an existing R-22 system and will be for several more years. A minor problem does not mean the entire system is junk and the owner must replace it.

Hi,

I know of a few boats that keep a Recovery Unit and a Recovery Bottle large enough for a complete charge from each system - All carefully recorded and detailed in the ODS which is of course available at any-time for perusal during an ISM Audit or PSC Inspection.

If these are reverse cycle (works as heater also) then this problem can be caused by a stuck 4 way valve stuck in halfway position.

Marmot, you just like to argue simply for the fact of argueing. I don't protest, I try to follow the rules, the law, and modern technology. In my post, I stated that if the repairs to a R-22 system are under $750 I would repair the unit. Anything over that price point on most all yacht split systems (non chilled water), means either a new condensing unit or air handler, and if you're going to spend $1250 on either one, you might as well buy an entire new unit with warranty and newer technology for $2500. Otherwise it's penny-wise and pound foolish in the long run. 80% of the time, if an air handler goes bad, or condensing unit, the other unit is only a few years (if that) away from going bad also. And considering R-22 is already 3-4x the cost it was a year ago, it isn't going to be economical to keep fixing an R22 system in future years.

I've also had a lot of experience with R-12 after the changeover, and the recycled/re-used R 12 was never nearly as efficient or effective as new/virgin R 12 was.

I don't know what part of the world you're hiring a/c tech's but I've seen several contractors I've used recover freon. I even had freon removed on a boat going to Australia, and they bothered putting a piercing valve on a sealed unit that only holds 4 ounces of R-22 so they could recover it.

But, you can go ahead and keep fixing junk and wasting owners money $500 at a time and aggrivating guests when they're on a trip and the a/c went down again.

Yes, I have seen this happen. I have also seen compressors start running hot when they are starting to go bad.

Skip, you really need to check water flow through the unit with a garden hose or something, and then you really need to put gauges on the unit and see exactly what the operating presssures of the unit are.........

Good for you.

Who cares is based on trashing a system now because if it was built after 2010 it cannot have R-22 replaced in 2015.

Trashing that system now is probably absurd and costly to the owner. If the decision to do so is based solely on the information you provided, it is poor economics. That system can probably be maintained by replacing components with modern versions that can be used with new refrigerants so a conversion is possible in the future.

I wouldn't trash a unit manufactured after 2010 and r22, however, I wouldn't put a ton of money into it either, minor fixes yes. The problem is, getting someone reputable to charge it, that can be a major pain the butt in some areas..........

Fair enough, especially if it is one of those little self-contained units. As far as charging goes, if you are supporting a boat that requires a lot of air conditioning and refrigeration work, it is worth buying the gear and learning how to troubleshoot and service them yourself.

I looked at this and there is still not enough information. Terms like warm, hot, very hot are meaningless to diagnose a AC system.

You need very accurate temperatures (within 1 degree) from a minimun of 4 test points to as many as 10. You Also need very accurte high side pressure and Low side pressure.

From the above You can calculate sub-cooling and Superheat,which relates to system charge and performance.

I also would need to know if the metering device is a cap tube,thermal expansion valve or a constant pressure expansion valve.

Not knowing this information is like sending a mechanic to work with a blind fold on and no tools,

This is good advice, but expect to spend at least 2 to 3 thousand in tools For starters you need a manifold gauge set(one for different refrigerants) temperature meter with @ least 2 to 4 in-ports. Recovery machine with recovery tank.You need a scale to weigh in the charge. Nitrogen tank with regulator for purging.Vacuum pump & tank of refrigerent. Plus small oxygen/acetylene brazing set. And some hand tools like tubing cutter,flaring set,swaging set,wrenches. A ac/dc amp/volt meter.Oh and a EPA certificate.

Here is more items that one should have.A micron meter to verify when a deep vacuum is reached. Maybe a electronic leak detector and a UV dye injection kit and UV lamp & a ultrasonic leak detector. I could go on and on.

Walt

I think you covered most of it quite well. The cost of that stuff might be recovered by a competent engineer in the first job.

I am not talking about acquiring the tools and training for a little boat fitted with a couple of self-contained 12kBTU air conditioners, though even the money saved knowing how to troubleshoot those things will quickly pay for one.

What I object to is the cell-phone mentality of a few "yacht engineers" whose primary troubleshooting technique is speed dial and the owner's check book.

It's true, actually you can get away with gauges, a good leak detector, and r-22, an infrared temp gun, and a few small tools. At least then you can diagnose most things, fix some, and then buy or borrow the others as needed. For example, if you need to vaccuum the system, it's because you have to change a part and had to open the system, and most likely you're going to have to go out and buy that part anyways.

I've thought about buying all of the stuff, I had all of it many years ago and sold it all when I got out of the automotive end of things. However, I manage/maintain 10 different yachts and there just isn't enough time in the day for me to do everything myself, and some things you just sub out, granted I get much better prices from vendors than an owner would.

Guys
Are any of you real A/c techs? Or just quoting specs and trying to stay in politically correct posture? For sure evident, you don't rely on A/C repairs for income.
I'm working on R22 stuff everyday. My freon is expensive but all I need is still available for repair. AND, it's in the suppliers where house when I need more. I can not replace a whole system with a R22 system but I can service anything that is installed or the owner installed yesterday (still new from e-bay). In case nobody noticed, there is a world of R22 stuff still available on line and not to badly priced. As long as it is out there installed, a proper tech can service it.
I still have R12 in personal stock. When it's gone, it will really be gone. My last purchase came in from the Bahamas 15 years ago. My old cars will always blow cold.
Anybody remember propane in the system, rite after ammonia? Heck, I think some heated ammonia systems are still out there but I was referring to just propane as the refegent. When the old stuff is gone, it's really gone.
It's going to be a long time before R22 stuff will be un-serviceable. No matter what dates are on on the books.
To help again the original post; If you have not found anything you can do your self, Call a real A/C tech. Or msg me and I'll find you a real tech.

He's out of St. Augustine which isn't too far from your neck of the woods.

I doubt many marine engineers rely on A/C repairs for an income,or would even care to. As a matter of fact there does not appear to be many A/C techs who repair rather than replace when it comes to the little hermetic units.

As a marine engineer I had to obtain training and certification in order to sail as "reefer engineer" on container ships and "reefer ships." It is part of the job to maintain large shipboard systems and reefer containers. I've worked on ammonia systems on reefer ships. Ammonia systems still exist in great numbers on factory ships and large fishing boats. All ammonia (and conventional) systems are "heated" or they wouldn't work, but if you mean ammonia absorption units, they are not common in the marine industry. The only ones I have seen are little propane fridges on a few small cruising yachts or in off the grid cabins in the woods.

You pretty much stated what I was trying to point out to our flea bitten pretender, that there is no reason to trash a system because some small part fails. I am appalled at the waste of owner's money by poorly trained "engineers" who resort to the cellphone and checkbook after missing weeks or months of the machinery trying to tell them that something is wrong.

Alright I am hooked again,
You know Lamont, you rarely if ever share anything in the way of useful up to date knowledge, it's more finger pointing, insulting and putting others down. I guess it's all you got?

I just called Dometic Marine Air Systems 954-973-2477 as that is the most popular brand I see on large yachts. I asked them if they still sell R22 system replacement parts for there older R22 systems. They said most of there suppliers stopped manufacture of the parts and it is a real 50 50 they will have the replacement part needed. Compressors, flow switches, commonly failed parts are most likely not in stock or available any more.

2010,11 I was working with a new build yacht with 6, 5 ton Marine Air chillers. 2 chillers failed while under warranty that where R22. Warranty repairs are always done the most economical way possible. The most economical way decided by Dometic was to replace both chillers with a brand new R410 unit without even attempting to repair the R22 units. I would not had thought that.

I am only trying to share my experiences that may help others to succeed with and I just might be wrong sometimes.