Hello all, Long time no see,

Here in New Jersey recently we had a really hot day, so i switched on the heat pump to cooling mode (after leaving if off all winter) and after about a day the fan on the compressor stopped working. After a swearing and kicking the side of the unit, which had no effect what so ever, I opened it up and found it fairly simple inside. I decided to replace the dual Run Capacitor first (I could have troubleshooted it with a meter, but I felt it would have been far less impressive then wildly guessing the cause) and if just so happened to fix the heat pump. So my question is this, given that the Goodman heat pump compressor unit is about 10 years old, would it be a good idea to purchase a replacement compressor 2 1/2 ton (30000 btu) for about $1,000 for the future when the compressor finally dies altogether I'll have a replacement to put in. Since manufactures are going to stop making R22 compressors in the future, I thought it be prudent to have one on hand. One estimate to replace the entire system with a R410a unit was $15,000 which is exactly 15 times what just buying a R-22 compressor would be.   

If you only use it for cooling TG, why not just buy and R22 dry condenser. When the time comes you can fill the system with NU22 or some such. R22 will hit crazy cost soon (i.e. more than $100/lb retail).

As Joe pointed out the price of R-22 will soon dictate the use of that refrigerant.The actual cost of the compressor and availability of the compressor will change as R-22 is phased out of production.On the market now are several alternative refrigerants than can be used on a R-22 system.These alternatives are now less expensive then R-22 and will be around for decades to come.I wouldn't panic but I would start budjeting for a new system.Technology is constantly changing and along with it higher efficiencies.

Posted By joe.ami on 17 Apr 2013 09:42 AM
If you only use it for cooling TG, why not just buy and R22 dry condenser. When the time comes you can fill the system with NU22 or some such. R22 will hit crazy cost soon (i.e. more than $100/lb retail).

I do use the system for heating, but only until the temperature drops below 40 degrees at night, then I turn off the system for the winter. Last week was the first time I turned on the system since November. Is NU22 a substitute for R22 systems? Can I use it with my existing air handler if I install a New compressor. What I want to avoid is having to replace the entire system, it's going to cost a lot, far more than any potential savings are going to be by replacing the entire system with a new higher seer rated system.
 

NU22 is a composite of roughly 50-50 R-125 & R-134a, with a small fraction of R-600. Not all manufacturers will warranty R22 systems charged with NU22 (R417A), so it's best to check first, but it's whole reason for being is as a drop-in replacement for R22 on existing systems.

Like R410A it has a somewhat higher global warming potential than R22, but effectively zero ozone depletion characteristics. Propane could also work in most R22 systems, with zero ozone hit and VERY low GWP, but refrigerant leaks then become explosion hazards. (Now kids, don't try this at home... :-) )

But there are now R410A heat pumps with decent heating output & efficiency even at 20F & below, and at NJ style outside design temps it may be worth the expense if it can be an all-in-one solution, depending on what fuel & system you're using for heating when you turn the heat pump off. Cooling savings are one thing in a heating-dominated climate, but heating savings can be quite substantial if you've been using propane, oil, or resistance electricity in lieu of a heat pump.

(Somebody is likely going to call foul for saying this on the geo forum, but what the hell...) $15K buys quite lot in ductless heat pumps, and MANY houses can be heated & cooled comfortably at higher efficiency than ducted air source systems for well under $10K (installed price) of ductless mini-split hardware, let alone $15K, and it would be hitting near-geo efficiency performance in that climate. If your existing ducts are in the attic above the insulation or in an vented crawlspace there is even more efficiency and raw-tonnage downsizing to be had by going ductless too.

But getting the right equipment and making it work involves some careful design analysis as to the whole house load, the room-by-room loads, and getting the right number & placement of ductless heads. The I-R-N idiot-approach of one-head per room almost never works, either on an efficiency or first-cost basis. Sometimes spending a bit on the building or auxilliary room-heating to lower the loads in the doored-off rooms remote from a ductless head may be in order. But 2 & 3 head multi-splits can handle quite a number of mid-sized houses comfortably for under $10K. On very open floor plan ranchers sometimes even a single-head approach can work.

Bottom line, an R22/NU22 replacement compressor may be cheap, but it may be money less-well spent, particularly if you're spending it NOW, since it's likely the basic unit has a decade or more left in it if you've primarily been using it in the cooling season, and very little in heating mode. By the time the thing craps out the evolution of the technology will have bumped up yet another notch or three. In the meantime, testing and air sealing the ducts and insulating them where appropriate will often squeak out double-digit improvements in system-efficiency (unless the duct designer was a total hack, which happens), which is likely to be a far better way to spend the $1000 than on a box that sits in the corner collecting dust until the fairly young Goodman turns it's final wheezing cycle.

I've got a clunky way-oversized R22 ~10 SEER York parked under the north-side eaves that's pushing 20 years old, but nowhere near compressor death, and at the duty cycle I'm running it we'll probably still have it in 2050 unless I get so sick of looking at it that I retire it early. :-) There's just no telling how long these things will last with minor repairs like capacitor replacements, but 20 years wouldn't be an unreasonable expectation, and you're just halfway there.

NU 22 and some of the other replacements are not quite drop-in's and performance does take a hit. Wheter that matters will depend upon load and size. I agree with Dana that your course of action is likely not money best spent.
Mini splits, geo counsels, new heat pumps (why 15K by the way are they planning to replace all the ducts or does it come with a super-model?) all likely cost a few more dollars, but make more sense.

Not that it matters, but I've read conflicting reports on NU22's efficiciency performance issues relative to R22. Some seem to indicate a modest boost to heating efficiency, if a modest hit to cooling efficiency, others put it at pretty neutral. It may be exact system dependent? Maybe I should take another look- it's been many months.

I'm sort of curious as to what the $15K system was, and what your current system is (model numbers/tonnage), and the size/type of house? So many existing systems are so ridiculously oversized (my central AC is a prime example) that they make no sense, and replacing the system with a right-sized-ANYTHING is the only proper way to address it, rather than swapping in a new oversized compressor when the old oversized compressor croaks. The compressor has to be reasonably matched to the coil and air handler, so you can't usually get there by simply downsizing the compressor.

There are several R22 replacements. All seem to have some tradeoffs. Some cost capacity, some need different expansion devices, some reduce efficiency.

Others with more data may refine this but let me run up that flagpole that there are generally two failures that are uneconomic to repair on a typical out-of-warranty air source system: Compressor failure or coil leak, and that both occur roughly half the time.

Though random events are NOT affected by our own decision making, a guy named Murphy would probably agree that a sure fire way to trigger a coil leak would be to purchase a spare compressor. The installed base of R22 systems as well as increasingly available drop ins suggests to me that replacement R22 compressors will continue to be available for years to come.

well said curt

Posted By engineer on 20 Apr 2013 08:26 AM
There are several R22 replacements. All seem to have some tradeoffs. Some cost capacity, some need different expansion devices, some reduce efficiency.

Others with more data may refine this but let me run up that flagpole that there are generally two failures that are uneconomic to repair on a typical out-of-warranty air source system: Compressor failure or coil leak, and that both occur roughly half the time.

Though random events are NOT affected by our own decision making, a guy named Murphy would probably agree that a sure fire way to trigger a coil leak would be to purchase a spare compressor. The installed base of R22 systems as well as increasingly available drop ins suggests to me that replacement R22 compressors will continue to be available for years to come.

While I haven't priced either recently, I was surprised about the concern about availabilty/pricing for R22 ref or compressors. 

The installed base of R-22 systems would seem MASSIVE (looking at combined residential, commercial, and industrial installations), and as engineer was implying ...  I would guess manufacturers will continue to supply the healthy demand for replacement compressors for a long time going forward.   

On the refrigerant, aside from the "drop in" replacements, I think the best way to predict the future is comparing with the past.  Comparing to the R-12 phase out .... 
1. I'm assuming the the R-22 installed base/volume is much larger than the R-12 installed base when phase out was begun... my reasoning is over the last 15-20 years a much larger proportion of buildings have become air conditioned.
2.  In the last 15-20 years, laws/regulations concerning refrigerant handling/tracking have become more rigorous and/or more rigorously enforced.  As a result I'm guessing a higher percentage of the R-22 will be recovered (rather than vented).

What am I missing?  The two factors above would leave me to believe that R-22 refrigerant pricing/availability will track or beat (cheaper/more available) what was experienced for R-12 just 15-20 years behind.... which again going out on a limb here... but I heard (no I don't believe everything I hear :)), the pricing had a sizeable run-up due to hording, followed by a more gradual decrease over several years to the point where it has been for many years now, a price not far off what it was before the phase out ??   I never checked it as I never needed any (R22 or R12) and the explanation sounded plausable.  

I'm hoping there are some out there with evidence/experience to back or refute any or all of the above.  :)

What I'm hearing about the R22 $ runup is that EPA became pissed off that despite huge fines for venting refrigerant, very little R22 is actually reclaimed and turned in. The whole charge is still routinely vented during repairs and changeouts. Technicians are required to have aboard service trucks a recovery machine, but word on the street is that the machine never actually leaves the truck.

For years I've used a program wherein a local parts house provides recovery jugs in exchange for a $95 deposit and exchanges them for free, making their money on the recovered refrigerant, I guess. With the run-up in wholesale R22 costs (contractors typically multiply wholesale cost by 4-10x to consumer, so this is something of a case of crocodile tears) I'm now hearing of programs that pay $2-3 per pound for R22 turned in. That may turn the tide as Jokin suggests. If enough volume is turned in for rebate and the installed base of R22 gradually falls, R22 may go the way of R12, rising to a sharp peak and then becoming cheaper with declining demand.

TG....what does that 15 grand include?