R22 myths or facts?

[obxdist]

Where is twilli when you need him?

[indiana34]

So if you buy a house that has an R22 system in it and you need service and the tech charges your system with R22 cause that's what the system was designed for but turns out that someone had converted it to some other gas and now you are being charged a lot of money to have everything fixed properly.......who you gonna blame?

I would, of course blame whoever put the "wrong" gas in, or didn't make conspicuous note of the change. However, that is not my point.

My point was that a buyer of a house is not going to know or care until that happens. How often does that scenario happen? How often do people change refrigerants in essentially brand new air conditioners? The OP should buy whatever system he wants and not fall for the line that it will be a big issue at the time of sale.

What fraction of homebuyers spend time on this or related boards and are even aware of the R22/410A story? 1%? 0.1%

By the way, is there any law that requires a modified unit be so marked? Sounds like there should be, if the stakes are that high.

If you want to impress someone at time of resale, put in granite countertops or something the buyer can see. Better yet, put in a geothermal system; I read on that innerwebthingy they are so great that $20 bills start flying out of the registers.

[emcoasthvacr]

410a gets slightly better efficiencies due to both higher refrigeration effect (72.2 vs 69.9 btu/lb) and lower required refrigerant circulation (.77 vs .81 lb/min). These values are per ton of capacity.

But I believe 410a doesn't make economic sense due to the higher system pressures and subsequent maintenance & system failures that will accrue -- 410a is a bandaid at best.

I wouldn't be surprised to see CO2, propane, and ammonia systems replace the CFC's & HCFC's within the next 20 to 30 years in the residential market.

After getting kicked out by CFC's & HCFC's, C02 is making a comeback, & ammonia is 7 times more efficient as a refrigerant than either 22 or 410a.

[RoBoTeq]

Hey, twilli i am not a pro business professional ... only a pro tech ,... but i can sell more **** than home depot......... am i only permitted in certain forums ???I'm sorry I'didnt meant to say sh$t !!! Limited access...member ???

Let me guess; drunk again, eh?

[RoBoTeq]

410a gets slightly better efficiencies due to both higher refrigeration effect (72.2 vs 69.9 btu/lb) and lower required refrigerant circulation (.77 vs .81 lb/min). These values are per ton of capacity.

But I believe 410a doesn't make economic sense due to the higher system pressures and subsequent maintenance & system failures that will accrue -- 410a is a bandaid at best.

I wouldn't be surprised to see CO2, propane, and ammonia systems replace the CFC's & HCFC's within the next 20 to 30 years in the residential market.

After getting kicked out by CFC's & HCFC's, C02 is making a comeback, & ammonia is 7 times more efficient as a refrigerant than either 22 or 410a.

Ummm, there are reasons why these refrigerants were replaced. Ammonia leak in the house; uhhhh, yea

[kuryakin]

For most vendors, the price diff between R22 and R410a units of the same SEER rating and features is negligible, and often the R410a systems are slightly less expensive.
Now, of course, there will be vendors who will try to soak you, so be a careful consumer!

Should there be a cost difference between them? WIllt he 410a unit be more expensive? or cheaper?

Thanks Guys... Learning a lot from you.....

[kuryakin]

All that, and the vapor density of R410a is about 50% higher due to the MUCH higher pressure, therefore better heat transfer.

Where did you get that ammonia is 7 times more efficient? If it were, manufacturers would be falling over themselves for SEER 70+ systems!! <G>

410a gets slightly better efficiencies due to both higher refrigeration effect (72.2 vs 69.9 btu/lb) and lower required refrigerant circulation (.77 vs .81 lb/min). These values are per ton of capacity.

But I believe 410a doesn't make economic sense due to the higher system pressures and subsequent maintenance & system failures that will accrue -- 410a is a bandaid at best.

I wouldn't be surprised to see CO2, propane, and ammonia systems replace the CFC's & HCFC's within the next 20 to 30 years in the residential market.

After getting kicked out by CFC's & HCFC's, C02 is making a comeback, & ammonia is 7 times more efficient as a refrigerant than either 22 or 410a.

[emcoasthvacr]

the ability of a refrigerant to absorb heat across the evaporator. Ammonia is 7 times higher.

As robo alluded to, it's a B1 refrigerant that is hazardous to work with -- mostly used in commercial & industrial applications.

I don't think it's anymore hazardous than natural gas and like natural gas, utilizes steel pipe because ammonia would eat through copper tubing & heat exchangers.

All that, and the vapor density of R410a is about 50&#37; higher due to the MUCH higher pressure, therefore better heat transfer.

Where did you get that ammonia is 7 times more efficient? If it were, manufacturers would be falling over themselves for SEER 70+ systems!! <G>

[kuryakin]

Ah, OK. Thermal conductivity and heat of vaporization are VERY different from efficiency!

I agree, propane and propylene based refrigerants are getting worse press than they deserve. After all, how many folks keep a grille cylinder of propane in the garage?

Flammable? Yep. Toxic? No.

Ammonia is a whole 'nuther animal from a safety and engineering standpoint. Steel? I can see the rusted out evaporators and condensers now. And NH3 IS toxic as hell.

The only way I see ammonia making it is with a glycol loop to the indoor unit. With ALL the refrigerant outdoors, it may pass muster.

The real question will be, will it pass on liability and the lawyers that come with this?

the ability of a refrigerant to absorb heat across the evaporator. Ammonia is 7 times higher.

As robo alluded to, it's a B1 refrigerant that is hazardous to work with -- mostly used in commercial & industrial applications.

I don't think it's anymore hazardous than natural gas and like natural gas, utilizes steel pipe because ammonia would eat through copper tubing & heat exchangers.

[tpa-fl]

The only way I see ammonia making it is with a glycol loop to the indoor unit. With ALL the refrigerant outdoors, it may pass muster.

The real question will be, will it pass on liability and the lawyers that come with this?

There's still ammonia-absorbtion refrigerators out there and still plenty on the market. They're usually fueled by natural gas or propane, often used in areas where electricity is terribly expensive or generated on-site with renewable energy. Imagine that one, both flammable gas + ammonia in one appliance. They're actually not that bad... BUT, I don't think I'm ready for a split AC using ammonia in my home. Seeing how many systems are low on freon out there and how many techs are willing to "just give it a little freon", we're not ready for ammonia-based systems for residential apps. With one of my jobs having an ammonia-based chiller system, I've seen first-hand what happens when maintenance is neglected and it's not pretty. I can only imagine how bad this would go with the normal neglect homeowners dish out on their systems.

[RoBoTeq]

When I worked in large ice manufacturing plants I was told in no uncertain terms; "if you smell ammonia, keep as low as you can and get out of the building as fast as you can. Do not stop to pick up tools or for anything else, you do not have time."

That's enough for me to not take a chance on having large quantities of ammonia leak in my home.

[kuryakin]

And the COP of absorption cycle machines, on a REALLY good day, MAY get up to 1. The COP on MVR machines can go past 3 with good design.

There's still ammonia-absorbtion refrigerators out there and still plenty on the market. They're usually fueled by natural gas or propane, often used in areas where electricity is terribly expensive or generated on-site with renewable energy. Imagine that one, both flammable gas + ammonia in one appliance. They're actually not that bad... BUT, I don't think I'm ready for a split AC using ammonia in my home. Seeing how many systems are low on freon out there and how many techs are willing to "just give it a little freon", we're not ready for ammonia-based systems for residential apps. With one of my jobs having an ammonia-based chiller system, I've seen first-hand what happens when maintenance is neglected and it's not pretty. I can only imagine how bad this would go with the normal neglect homeowners dish out on their systems.

[emcoasthvacr]

We also need to consider that Ammonia has not only a much lower viscosity than either R22 or 410a but also has a specific heat 4 times greater than either R22 or R410a – Ammonia has both superior heat transfer qualities and energy capacity (it absorbs & retains energy) – one of the few elements with a higher specific heat than water -- and we know how important water is for chillers & refrigeration.

Also, a fluid with high specific heat and lower viscosity saves tremendous energy in the vapor compression cycle by reducing compressor wear and energy transfer & transport.

More importantly, HP’s on ammonia cycles have achieved COP’s around 10 and are widening the gap from refrigerant HP's in the low 3 COP range -- I know some of you guys have gas lines in the house an schedule 40 pipe or other ferrous alloys doesn't leak if installed properly.

[indiana34]

I am no pro, and haven't stayed in a Holiday Inn of late, either, but even I know that modern CFC refrigerants were invented and dominate the market currently is due to the toxicity of things like ammonia and the flammability of all alkanes.

CFCs are remarkably safe with respect to acute toxicity to humans. To be killed by CFCs you have to be suffocated by them. There is more toxicity in the lubricant oils mixed with the modern refrigerants than in the refrigerants themselves.

When did ammonia go out as a refrigerant for the masses? The 1950's? Was it ever used much in residential HVAC or refrigerators?

All the incremental improvements in refrigerants come at an extremely high cost, and frankly may not be worth it.

Why are we thinking about going backwards?

[tpa-fl]

When I worked in large ice manufacturing plants I was told in no uncertain terms; "if you smell ammonia, keep as low as you can and get out of the building as fast as you can. Do not stop to pick up tools or for anything else, you do not have time."

They're not kidding... One night I caught a pretty good whiff of ammonia as I was leaving the building (ice rink) and it took the wind right out of me. Gotta love the architect & engineer on this building -- the exhaust for the chiller plant blows downwards, right on 3 exits of the building. Not 3 exit doors, but 3 separate exits! Those #$#$#@$#@ never actually think about people having to USE and WORK within buildings they design.

[kuryakin]

Ammonia was never 'in' for the masses. Hopefully, it never will be. The stuff just has too many problems to outweigh its benefits. Steel lines rust from the outside. It's both toxic and flammable.
Freons were invented in the 1920s, I believe, and it was their invention that made AC and refrigeration available for the masses.

The costs are worth it. The performance of MVR ammonia systems compared to HFC refrigerant systems, looking at system efficiencies, are not very different.

Get the lawyers out of the act, and MAYBE we'll see hydrocarbon refrigerants. Even then, again, the performance compared to common refrigerants isn't much different.

I am no pro, and haven't stayed in a Holiday Inn of late, either, but even I know that modern CFC refrigerants were invented and dominate the market currently is due to the toxicity of things like ammonia and the flammability of all alkanes.

CFCs are remarkably safe with respect to acute toxicity to humans. To be killed by CFCs you have to be suffocated by them. There is more toxicity in the lubricant oils mixed with the modern refrigerants than in the refrigerants themselves.

When did ammonia go out as a refrigerant for the masses? The 1950's? Was it ever used much in residential HVAC or refrigerators?

All the incremental improvements in refrigerants come at an extremely high cost, and frankly may not be worth it.

Why are we thinking about going backwards?

[kuryakin]

Got any references we can check on this? If true, this would be neat! Alas, I haven't seen any number anything like this, so, if you could share, that would be great.

We also need to consider that Ammonia has not only a much lower viscosity than either R22 or 410a but also has a specific heat 4 times greater than either R22 or R410a – Ammonia has both superior heat transfer qualities and energy capacity (it absorbs & retains energy) – one of the few elements with a higher specific heat than water -- and we know how important water is for chillers & refrigeration.

Also, a fluid with high specific heat and lower viscosity saves tremendous energy in the vapor compression cycle by reducing compressor wear and energy transfer & transport.

More importantly, HP’s on ammonia cycles have achieved COP’s around 10 and are widening the gap from refrigerant HP's in the low 3 COP range -- I know some of you guys have gas lines in the house an schedule 40 pipe or other ferrous alloys doesn't leak if installed properly.

[jayhvac]

i was referring to 417A,B,C,D R-422A/B. "Nu-22". I haven't been around enough to see the older mixtures, but the new ads don't seem to tell the whole truth.

[total home]

stick with the old bread and butter r22 stillcheaper in the long run, you will probably need another one by that time anyway

[BigJon3475]

But I believe 410a doesn't make economic sense due to the higher system pressures and subsequent maintenance & system failures that will accrue -- 410a is a bandaid at best.

Parents system is coming up on 12 years old and is still working the same as it did new according to my parents. They change the filter regularly and have it looked over once a year. Its a 410A gas Pack.