A/C Compressor Out- Real Surprise

[Tex1001]

Compressor in my 42 year old unit bit the dust 15 days
ago. I'm still a contractor so costs are minimal.
New 5 ton unit for $2100. Scroll compressor (Good).
Charged with 410a (Bad).
Recover the 410a, install the unit, flush, evacuate,
charge with R22.
Surprise!
New unit draws 11.6 amps (VERY good) because
drum roll:
Old unit drew 29.8 amps.
I knew that the new units were efficient,, but WOW.
Why did I wait so long? Now I can run it off of my generator
during a power outage.

It was ALMOST worth melting in 105 deg heat for the install.

 

[Tex1001]

Want to add-
My heart really goes out to anyone who has to have
any A/C work done this summer.
I know that I don't work cheap, except for myself.

 

[sophie]

Where in the world did you find R22 refrigerant? Been scarce here for years. Last I bought for my old unit 4 years ago, I gave $80 for just over 2 lbs.
I bet you had some saved back.

 

[Tex1001]

I'm sitting on 90lbs that I bought 15 years ago.
ETA:
When I use it on a job I charge $75/lb.
I REALLY dislike the politics involved in refrigeration work.
ETA:
I meant to say I charge $75 per pound.
MY COST is $50 per pound.

 

[ZGrand]

If you got 42 years out of your first compressor, you're way ahead of the game. I thought I was doing good to get 26 out of mine.

 

[Tex1001]

It was almost 20 years old when we moved in 26 years ago.
I really know how to baby a system.

 

[Tex1001]

If you got 42 years out of your first compressor, you're way ahead of the game. I thought I was doing good to get 26 out of mine.

I just read your post completely.
The SYSTEM is 46 years old. Compressor burnout fer the old
owners was 42 years ago. I have their records.
BTW, original installation was TOTALLY botched.

 

[LVSteve]

I'm not certain if it's legal to refill a system with R22 in this state.

 

[Tex1001]

I'm not certain if it's legal to refill a system with R22 in this state.

For years I bought condenser units that were pre charged
with nitrogen for use with any legal refrigerant.
R22 is still a legal refrigerant.
I could charge a system with Coca Cola if it would work.

 

[Eric300]

Funny this post popped up when it did. MY AC coil went south on me. Just had it replaced 2 days ago. $2000.00! That stung a bit....

(*Edited for PD ) - This is a pic of the old one.

 

[Protocall_Design]

That $2000 replacement doesn't look all that great...

Edited for Eric - I was kidding.

 

[tlawler]

This is the first I've heard of someone retrofitting an r-410a unit with r-22. You didn't mention changing your AHU, so I'm assuming it's got an r-22 txv in it. I guess it might work, biggest thing would be flushing all the mineral out of the air handler so it doesn't mix with the poe. Compressors are supposed to be specific to refrigerant due to differing compression ratios, but that might just be sales hooey. It'll be interesting to see the long term effect. I do know they are experimenting with using r-32 as a drop in replacement for r-410a.

On another note, we have had excellent results converting some of our medium tonnage air cooled chillers from r-22 to r-407c. These are on York YCAS machines with 70, 85, and 100 ton circuits. Charge weight is reduced by 30-35% and tonnage is 90-95% of the r-22 performance. On the larger four circuit 400 ton machines, it comes out to 690 lb. of r-407c vs. 920 lb. of r-22. At our cost, that's $42K+ for r-22 vs less than $9K for r-407c. That's on one machine and we have close to 20 in our mobile fleet. And being mobile and bouncing down the road, they tend to spring leaks fairly frequently. I've never done it on a residential unit, but I've got friends in the resi and light commercial side that have done it and say it works well. Biggest thing again being getting rid of all the mineral oil and replacing it with poe. The advantage on the chillers is that they already use poe with r-22, so recovery and a deep evac is all that is needed.

 

[oldbrownhat]

Compressor in my 42 year old unit bit the dust 15 days...

New unit draws 11.6 amps (VERY good) because
drum roll:
Old unit drew 29.8 amps.
I knew that the new units were efficient,, but WOW.
Why did I wait so long? Now I can run it off of my generator
during a power outage....

Bravo! Your electricity supplier and other customers will be thankful for your upgrade.
Now if this project at Harvard eventually develops into affordable cooling units, A/C operating costs will drop dramatically as there won't be a compressor at all

 

[Tex1001]

This is the first I've heard of someone retrofitting an r-410a unit with r-22. You didn't mention changing your AHU, so I'm assuming it's got an r-22 txv in it.

I do know they are experimenting with using r-32 as a drop in replacement for r-410a.

On another note, we have had excellent results converting some of our medium tonnage air cooled chillers from r-22 to r-407c.

On the retrofitting, I've done it before with no problems.
I do have an R22 TXV. I don't trust my evaporator with R410a
pressures.
Compressors will work across the entire spectrum of
refrigerants. Only difference is oil and POE will be fine with R22.
I've found that head pressures in a scroll with R22 run slightly
lower.
Temp delta inside is 15F to 18F, but doesn't feel muggy.
Probably won't find any "drop in" replacements for
anything.
How do pressures/temps compare between R22 and R407c?

 

[Tex1001]

I should mention that I taught residential/commercial/industrial
refrigeration classes on a college level for 17 years.

 

[Tex1001]

Bravo! Your electricity supplier and other customers will be thankful for your upgrade.
Now if this project at Harvard eventually develops into affordable cooling units, A/C operating costs will drop dramatically as there won't be a compressor at all

ColdSNAP or dryscreen may go somewhere, someday, but it would surprise me.
It would equally surprise me if Peltier type thermoelectric cooling should prove feasible on a large scale.
At my age, I expect to be surprised at everything.
Never say never.

 

[Tex1001]

Funny this post popped up when it did. MY AC coil went south on me. Just had it replaced 2 days ago. $2000.00! That stung a bit....

Real bummer. I'm constantly surprised at how clean/clear my
evaporator is.

 

[lkabug]

I'm still feeling the pain in my wallet, having just replaced my complete unit.
Six days of high ninety degrees. Thank goodness contractor loaned me a window unit, and my neighbor loaned me a portable unit. I should be good for a few years now.

 

[Tex1001]

Six days of high ninety degrees. Thank goodness contractor loaned me a window unit, and my neighbor loaned me a portable unit. I should be good for a few years now.

In Texas, a 90 deg day comes on Thanksgiving or in March.

ETA:
I do have 4 small window units left from my teaching days.
I used 2 of them to give us a safe haven.

 

[oldbrownhat]

ColdSNAP or dryscreen may go somewhere, someday, but it would surprise me.
It would equally surprise me if Peltier type thermoelectric cooling should prove feasible on a large scale.
At my age, I expect to be surprised at everything.
Never say never.

As they say, "A pessimist is never disappointed"

They're predicting it may be ready in 5 years. It would have to be adopted by one of the major manufacturers to get it to market.

But it's an interesting line of development as we need to watch our electrical demands. I was reading recently that most portable A/C units haven't changed much in decades and use more power than they should, with a few (expensive) units being the exception.

As regards regular technology, from what I've read (and I'm not in "the biz"), the next performance improvement in refrigerants is CO2, although it works at higher pressure so can't be swapped out for current refrigerants (?) I think Mitsubishi has units in production, but only for commercial applications so far.

 

[Tex1001]

As regards regular technology, from what I've read (and I'm not in "the biz"), the next performance improvement in refrigerants is CO2, although it works at higher pressure so can't be swapped out for current refrigerants (?) I think Mitsubishi has units in production, but only for commercial applications so far.

So far, CO2 is applicable for low temp units, I believe.
They may be able to use it with high temp units, but I don't
see how.

 

[tlawler]

On the retrofitting, I've done it before with no problems.
I do have an R22 TXV. I don't trust my evaporator with R410a
pressures.
Compressors will work across the entire spectrum of
refrigerants. Only difference is oil and POE will be fine with R22.
I've found that head pressures in a scroll with R22 run slightly
lower.
Temp delta inside is 15F to 18F, but doesn't feel muggy.
Probably won't find any drop in replacements for
anything. How do pressures/temps compare between R22 and R407c?

Pressures are slightly higher with 407c at a corresponding temperature, but so close that it's hard to determine which refrigerant is in a system from gauge pressure alone. Very important that a system be clearly marked once it's been converted. The one modification we have to make is installing a temperature sensor on the suction line coming out of the evaporator near where the txv bulb would be on a non-eev system. We then program the micro board to shut the circuit down if it reaches 25 degrees to prevent freezing in the evap. We had to experiment with that setting a bit…any higher and you get nuisance trips because the txv or eev can't respond quickly enough to the slide valve in the compressor loading.

 

[tlawler]

I should mention that I taught residential/commercial/industrial
refrigeration classes on a college level for 17 years.

I'm looking to put away the tools myself here in a couple of years and get into teaching. I had thought about going the vo-tech route, but I think if I stick with the rental industry, I can get into training our up and coming chiller techs. That way I think I can keep my pay up close to what I'm making now, even if it means traveling a lot more. The rental industry is absolutely booming, almost all of our machines are out now. We are having a lot of trouble getting new units, even ones that were promised to us because certain tech companies are willing to pay "a premium" to have their chiller orders expedited. That's a big part of the reason we are literally resurrecting 15 year old chillers and converting them to keep up with the demand. I can't wait until we are fully changed over to all r-134a chillers with vsd compressors, both screw and centrifugal. It will make life (and getting parts) so much easier.

Sorry for the thread drift

 

[jeffrefrig]

Reading this made me so glad I retired from the business 3 years ago. Just a few weeks ago I sold 20lbs. of R22 to a guy for $300. He was happy and I was just glad to get rid of it. I have about 7lbs. left in another cylinder if mine should happen to spring a leak somehow before I have my system replaced. I have around 30 lbs. of R12 I need to get rid of; it's just taking up space. There may be a backyard mechanic that may want it, but by now most of the R12 boxes have pretty much all been replaced. Even the 134A I have is pretty much useless now days.
Did I mention I'm glad to be out of the business? It was a good living, for sure.

 

[SMSgt]

I just had a new system installed a couple of months ago ($8300), the old one being 13 years old. My AC is running all but about two weeks a year, taking a few days off during the S FL "winter," so lifespan is not all that long.

Back in the day, I used F-22 to troubleshoot fuel quantity indicating systems on B-52s. I pumped a whole lot of F-22 into the air. No one gave it a second thought back then. My AC guy said the next coolant coming down the line contains butane. I can see that going bad.

 

[tlawler]

Reading this made me so glad I retired from the business 3 years ago. Just a few weeks ago I sold 20lbs. of R22 to a guy for $300. He was happy and I was just glad to get rid of it. I have about 7lbs. left in another cylinder if mine should happen to spring a leak somehow before I have my system replaced. I have around 30 lbs. of R12 I need to get rid of; it's just taking up space. There may be a backyard mechanic that may want it, but by now most of the R12 boxes have pretty much all been replaced. Even the 134A I have is pretty much useless now days.
Did I mention I'm glad to be out of the business? It was a good living, for sure.

134a is still widely used. All of our York VSD screw and centrifugal chillers are 134a, with the largest (that we have) YK 1000 ton using around 3000 lb. of refrigerant. Along with York(JCI), Trane, Carrier, and Daikin(McQuay) all are still manufacturing 134a machines.

I doubt if I'll ever get out of the trade completely. I've been in it since I was 18 and I'll be 62 my next birthday. I am, however, definitely going to put away the tools and do it from an air conditioned classroom.

 

[NYlakesider]

Talked with my cousin that lives in lower Alabama. She, originally from upper NYS says it is brutal down there.

At her age of 80, is a widow lives alone and the fact her AC unit is quite old she is very worried it will quit. She did have it serviced and recharged last year, so that is good news to me.

 

[Heymatt]

Very interesting. With all the different less costly, R22 replacement refrigerants. R410a prices are climbing and on it's way out in 2025. I'd be interested how it performs long term.
Always looking for out of the box solutions to problems.
Not looking forward to the " non self propagating flame" refrigerants.
63 is the next one for me. Still in the trade for another 5 years or until my body decides otherwise.

 

[oldbrownhat]

So far, CO2 is applicable for low temp units, I believe.
They may be able to use it with high temp units, but I don't
see how.

I can't remember where I read about it. The "fine print" of much of this goes over my head as I'm not in the A/C business. I did come across one reference on R744.com from 2021 to Mitsubishi's CO2 cooling units being used in Sweden.

This may have been where I first read about CO2: Mitsubishi Launches CO2 Heat Pump Water Heater in the U.S as I've been following the "heat pump hysteria" on case I were to move at some point and if local regs. required that new building (or even replacement of older equipment) not use fossil fuels for heating. Up here in the (so far) temperate PNW, cooling is less critical, although as comments here on the Forum have indicated, it depends what you are used to. We are definitely not accustomed to 100+ temperatures up here! As a result, we have less A/C installed and when those temps hit, as they did in 2021, many people really suffer, usually the elderly and infirm and homeless. There were several hundred deaths attributed to the heat wave that year.

The earth tube I trenched in last year (120' of 6" PVC pipe, 5-6' down) seems to suffice for me so far, although if we were to have another heat dome as we did in 2021 it might be less effective.

I'm fortunately not in a big "heat sink" city but it hit 103º on June 28/21, which is about 10ºF higher than normal for our summers. (That was the same summer a wildfire burned Lytton, BC to the ground.) Conversely, almost exactly 6 months later, it dropped to 0ºF, about 10º lower than we used to get.

Somebody or something's messing with us somewhere!

 

[Tex1001]

134a is still widely used. All of our York VSD screw and centrifugal chillers are 134a, with the largest (that we have) YK 1000 ton using around 3000 lb. of refrigerant. Along with York(JCI), Trane, Carrier, and Daikin(McQuay) all are still manufacturing 134a machines.

The phaseout of 134a infuriates me. ODP (Ozone Depletion
Potential) is ZERO. I still question GWP numbers and usage.
ETA:
I've never heard of any cent chillers using R134a. Thought its
operating pressures are too high.