R-22 vs. R410a (Puron)

[Jay-n-123]

Which systems are more reliable, those that use R22 vs. R410a? Are R410a systems REALLY as reliable R22?

I live in a condo and replacing the refrigerant lineset would involve ripping up the ceiling drywall. My AC system is 20 years old. Wondering the best solution would be to get a new R22 system (with existing refrigerant lines) installed before 2010. If the existing system were to die after 2010, then only systems that use 410a will be sold, and I would have to hope and pray that cleaning/purging out the old lines REALLY is going to be sufficient for a reliable 410a system. What do you think?

Thanks,

J.

[<kjpro]

Depends on the installer.

You&#39;re likely to be screwed either way, if the lineset isn&#39;t large enough for the new high S.E.E.R. equipment.

[Lloyd E. Sponenburgh]

In our area, I&#39;m beginning to notice a few common trade practices (that might be unique to around here), and wonder if you could flesh out the reasoning for one of them.

Except for slab construction, I&#39;ve noticed that nobody seems to use chases or conduits through which to run linesets. I&#39;ve even seen a few cast right into slabs without the first bit of pipe around them. It seems to me that some 4" or 6" thinwall waste pipe would be a great investment toward future upgrades. For any set shorter than 100&#39;, it would be pretty inexpensive, too.

I have seen a lot of water in the couple of grade-level or below-grade sets I&#39;ve pulled out of conduit, and suppose that might be one objection to using it. (Ken _likes_ it that it&#39;s my hands and not his in that stagnant goop...)

Are there other reasons - besides the basic cost of materials and labor - that make conduit/chase installation of linesets undesirable?

LLoyd

[Richard J Kinch]

R-22 runs at much lower pressures and systems using it are therefore cheaper and more reliable, other things being equal. A given 410a system could be reliable enough, but only at some higher relative cost.

410a systems only exist because of politics, not technical merits.

[Jay-n-123]

Do you think I should plan on gettting a new R22 system by 2009 since they stop making R22 systems in 2010? (My existing system is 20 years old)

[Noon-Air]

According to the Rheem tech rep, if the lineset is correctly sized, blowing it out with N2 real well and using a little lineset flush is sufficient for a new R-410a system. Contrary to popular belief, R-410a is a more efficient refrigerant, and requires a smaller compressor. The same size of R-22 system in the same efficiency will use twice the amount of refrigerant to do the job. The real catch is if the lineset is correctly sized. As far as reliability, I have recently replaced 35 year old R-22 systems with R-410a....I can&#39;t say about the longevity with the new because it hasn&#39;t been around that long.

[Noon-Air]

Gotta love it when the lowest bidder gets the job

There is a reason that your supposed to seal both ends of the chase

[Noon-Air]

Currently, the R-22 systems are more expensive that the R-410a systems of the same size and efficiency

[Lloyd E. Sponenburgh]

So, by that, do you mean it _should_ be done, and just isn&#39;t to save time/sweat?

The two I pulled _were_ "sealed" somewhat -- one only with foam (spray-on) and one with foam and capped with mortar at the outside end; and of course, the mortar was cracked. On both, the inside end was sealed with foam. I presume the water was from condensation and not from leakage. Seems like only a good hermetic seal would prevent the pipe from breathing under temperature changes.

What should be used? Is there a fitting designed to the purpose?

You may have answered that there aren&#39;t... but I didn&#39;t read that clearly.

LLoyd

[Noon-Air]

yup... if the lineset is in the slab, a PVC chase is required.

I use the expanding foam on both ends.... it seems to work well enough. The only things I run through the lineset chase are the lineset and the control wires. No I don&#39;t tie the lineset and wires together or tape them.....I have had to replace too many wires that were taped or tied. I don&#39;t staple them inside of the walls either.

Just use the expanding foam.....its a good idea to make sure that the inside of the chase is clean and dry before you run the copper.

nope, and the only additional cost is $10 in 4 inch drain pipe

[Richard J Kinch]

Please explain.

[Noon-Air]

Ok..... 2 heat pumps, 4 ton, 13 SEER...same series......

RPNL-048JAZ 13SEER R-410a heat pump takes 11.5lbs refrigerant and rated 21.8 RLA(measured amp draw on the compressor is 12.8 - 13.2 amps) Copeland compressor # ZP42K5E-PFV-130

RPNE-048JAZ 13SEER R-22 heat pump takes 19.8lbs refrigerant and rated 22.7 RLA (measured amp draw on the compressor is 17.6 - 18.0 amps) Copeland compressor # ZR45K3-PFV-835

The R-410a compressor is also physically almost half the size of the R-22 compressor. Using half the amount of refrigerant, half of the coils(single layer instead of double layer coils in the condenser/heat pump), and a smaller compressor, to give the same or greater efficiency at the same BTU capacity, makes R-410a more efficient......almost twice that of R-22.

[Andy Asberry]

A little more info on the lineset size, please. Does R-410a require a different size line than R-22?

--Andy Asberry--

------Texas-----

[Geoman]

I was on a job once and saw perforated pipe used. The contractor told me that there was a perimeter drain and the refrigerant lines were above the tile, so instead of sealing off the ends with foam he stuffed them. His idea is that any condensation leaks would be leached. Interesting way he thinks

[Noon-Air]

ummmmm...... yeah......ok........

[Puddin' Man]

Please to compare (say, contractors) cost of 11.5lbs of R-410a (which is not 1 refrigerant but a combination of 2) vs 19.8lbs of R-22.

80+% of residential cooling is done without heat pumps. Any particular reason to illustrate with heat pumps?

This comment was appreciated.

Thx, Puddin&#39;

"Mit der Dummheit kaempfen Goetter selbst vergebens!" -Friedrich Schiller

[New Directions In Building Ser]

Noon-Air That might be ok where you are but if your talking about apartments or commercial where some form of fire separation/segregation is required. Expanding polyurethene sealants are forbidden in these instances so you might like to/should reconsider and used an appropriate intumescent (fire rated) mastic sealant.

As to the practice of pouring concrete over the linesets - sounds like a whole lot of liability exposure to me...

[Longtime Lurker]

Hey, that&#39;s a great idea! How much radius do you think you need on the curve to pull a lineset through 35&#39; of horizontal pipe and then up a foot or two into the HVAC closet?

[Noon-Air]

I only use the expanding foam where the lineset is inside of a PVC chase inside of the slab. 99% of what I do is single family residential. Apartment owners and commerical building owners around here only want the lowest bidder.

The linesets are encased in a PVC pipe chase inside of the slab so there is no direct contact between copper and concrete. The PVC pipe chase also makes it a lot easier to change the lineset when needed.

[Noon-Air]

Just put a 45 degree elbow (long radius prefered)on the pipe where it comes out in the closet floor.