r22 to 410

[dvschillin]

I have recently started working for a company that doesn't change the line set when they convert from r22 to 410 and the guy training me acts like it will take too long to put a vaccum pump on the system. I am wondering if purging the lines with nitrogen or even a good vaccum is enough.

any ideas would be greatful

[Special Ed]

Purging w/nitro will help but you will never be able to leave the vacuum on the system long enough to remove all the moisture (if there is any) from the lineset. My recommendation is to flush the lineset w/Rx11 flush or equivalent if it's not possible to replace the lineset. At the very least.

[SerafinsAC]

Purging w/nitro will help but you will never be able to leave the vacuum on the system long enough to remove all the moisture (if there is any) from the lineset. My recommendation is to flush the lineset w/Rx11 flush or equivalent if it's not possible to replace the lineset. At the very least.

^This.

[crmont]

......and the guy training me acts like it will take too long to put a vaccum pump on the system......

:eek2:

why don't you train him?

[pauls heating &]

I have recently started working for a company that doesn't change the line set when they convert from r22 to 410 and the guy training me acts like it will take too long to put a vaccum pump on the system. I am wondering if purging the lines with nitrogen or even a good vaccum is enough.

any ideas would be greatful

w a good vac pump/hoses a vac shouldnt take long-not vacing a system
will lead to problems- i always vac mine to 500 microns..

as to not changing lineset-to me thats just as bad as not vacing system-
unless its a rare occasion where its not possible to change-

and if he reuses a lineset that had been soft soldered w 410 its bad too

sounds like real bad install practice/lazyness to me

[SerafinsAC]

Many times out here in Phoenix you can't change out the line sets because they're buried in the walls, it's just not possible unless the Home owner wants to pay a ton extra to get it done.

A good RX11 flush and a good triple sweep vacuum will get the job done.

[davo]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.
They do not recommend Rx11 flush.

They do recommend nitro purge while brazing, a good liquid line dryer rated for R-410a, and a proper vacuum.

They are even providing alternate refrigerant pipe sizes now.

We have been installing R-410a systems for over 15 years now, and have literally thousands and thousands of systems (replacements) and NO problems.

There is no excuse not to pull a vacuum, but replacing the line set when not needed is like changing a motor that does not need to be replaced.

With the cost of copper and armaflex, it costs a pretty penny to replace many line sets.

[big sky hvac]

There is no excuse not to pull a vacuum.

Couldn't agree more. Isn't that taught in A/C 101?! To me the same thing applies if the system is going to open to atmosphere, always install/replace the liquid line drier. If you don't do that, it's like changing the oil in a car and not replacing the filter. Always put in a new drier, always pull a vacuum!!

[clarkie]

I have a problem with Davo in not replacing the linesets. If you don't flush the lineset or purge the system correctly, you are asking for a Burnout!
The possibility of mixing mineral oil with Poe oil greatly exists when there is not a through flush of the system. And what if you don't know if the previous lineset was or wasn't blazed or silver-soldered.
Do you really need this type of future service issues?
Do the right thing and change the line to new virgin copper. Just include it in the cost of the job. If this cost keeps you from getting the job, guess what, you'll doing the work too cheap!

[crmont]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.

I call BS.

[clarkie]

And another thing, I cannot believe that davo said that the major manufacturers said they did not recommend changing the linsets.
I am a York dealer and they have said that they "highly recommend" changing the line sets. Like the person who spoke on this forum before me, sounds like a lot of BS.

[tocss]

if you have a line set that is not accessible like in dry wall. flush with rx 11 and it works pretty good.always change the line set if possible.i know carrier may not officially recommend the flush but its better than leaving oil and it turning into jello.vaccumb the unit to at least 500 microns

[dvschillin]

Thanks guys. I am just out of school and I do feel like I should be training my trainer but I just started with this company and finding a job is not easy these days especially in my circumstances. That is why I aked you all.
My plan is to do it the right way as much as possible without changing the line set, including purging, vaccuming, and drier just for my own consience. Then I know that in the long run my way will prove to be the best way. once I am in control of my own sales I will try yo alow for the line set in my price.
Thanks again guys for reaffirming what I thought anyways.

[dash]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.
They do not recommend Rx11 flush.

They do recommend nitro purge while brazing, a good liquid line dryer rated for R-410a, and a proper vacuum.

They are even providing alternate refrigerant pipe sizes now.

We have been installing R-410a systems for over 15 years now, and have literally thousands and thousands of systems (replacements) and NO problems.

There is no excuse not to pull a vacuum, but replacing the line set when not needed is like changing a motor that does not need to be replaced.

With the cost of copper and armaflex, it costs a pretty penny to replace many line sets.

Exactly the same here!!

[crmont]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.


Rheem says replace or flush;

[jimj]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.
They do not recommend Rx11 flush.

They do recommend nitro purge while brazing, a good liquid line dryer rated for R-410a, and a proper vacuum.

They are even providing alternate refrigerant pipe sizes now.

We have been installing R-410a systems for over 15 years now, and have literally thousands and thousands of systems (replacements) and NO problems.

There is no excuse not to pull a vacuum, but replacing the line set when not needed is like changing a motor that does not need to be replaced.

With the cost of copper and armaflex, it costs a pretty penny to replace many line sets.

Yup, I'm with Dash and Davo

[crmont]

Someone post some mfg. links that state "lineset replacement is not recommended".

[jimj]

Someone post some mfg. links that state "lineset replacement is not recommended".

Here ya go, as I read it is not required which means that will become the standard. The mixing of oils is not near the problem that was originally thought ( that comes from our Trane FSR).

[crmont]

Here ya go, as I read it is not required which means that will become the standard. The mixing of oils is not near the problem that was originally thought ( that comes from our Trane FSR).

I'm still looking for the "not recommended". What I see is;

[AggieEngineer]

Someone post some mfg. links that state "lineset replacement is not recommended".

See page 3...

[crmont]

See page 3...


That manual doesn't refer to the line set at all that I can tell.

[AggieEngineer]

That manual doesn't refer to the line set at all that I can tell.

Those who say it is "not recommended" to change the lineset are technically in error. The stance from at least Carrier/Bryant is that the lineset is not required to be changed out in a retrofit situation. Below is from page 3 of the service manual...

Add--On Replacement (Retrofit) -- R22 to Puron
Specifications for these units in the add--on replacement/retrofit
market require change--out of outdoor unit, metering device, and
all capillary tube coils. Change--out of indoor coil is recommended.
There can be no deviation.
1. If system is being replaced due to compressor electrical
failure, assume acid is in system. If system is being replaced
for any other reason, use approved acid test kit to determine
acid level. If even low levels of acid are detected install
factory approved, 100 percent activated alumina
suction--line filter drier in addition to the factory supplied
liquid--line filter drier. Remove the suction line filter drier as
soon as possible, with a maximum of 72 hr.

2. Drain oil from low points or traps in suction--line and
evaporator if they were not replaced.

3. Change out indoor coil or verify existing coil is listed in the
Product Data Digest.

4. Unless indoor unit is equipped with a Puronr approved
metering device, change out metering device to factory
supplied or field--accessory device specifically designed for
Puronr.

5. Replace outdoor unit with Puron(r) outdoor unit.

6. Install factory--supplied liquid--line filter drier.

[hmscool]

I always replace linesets when going frm r-22 to r-410a. was taught that years ago. If its not possible i have used rx11 flush,nitro ,and a drier. i also use seperate gauges for each. jmho

[jimj]

I always replace linesets when going frm r-22 to r-410a. was taught that years ago. If its not possible i have used rx11 flush,nitro ,and a drier. i also use seperate gauges for each. jmho


The key word is years ago. R11 flush is no longer advised unless it's a burnout.

[hmscool]

The key word is years ago. R11 flush is no longer advised unless it's a burnout.

I dont use unless there is a burnout and cant replace lines,guess i should of been more specific. I still do replace lines all the time when changing out a system tho.

[tedkidd]

Bpi heat pump class required epa608. Wasn't a bunch of this (separate gauges...) covered in that?

Was a while back but as I recall changing linesets was really strongly encouraged.

[crmont]

When is it not a burnout?

The truth is that when the system finally has issues, there is no way to prove that a contaminated line set 5 years in the past was the culprit.

[Octopus]

Carrier, Trane, Lennox, and all other manufacturers I can think of do not recommend replacing linesets, unless they are the wrong size.
They do not recommend Rx11 flush.

They do recommend nitro purge while brazing, a good liquid line dryer rated for R-410a, and a proper vacuum.

They are even providing alternate refrigerant pipe sizes now.

We have been installing R-410a systems for over 15 years now, and have literally thousands and thousands of systems (replacements) and NO problems.

There is no excuse not to pull a vacuum, but replacing the line set when not needed is like changing a motor that does not need to be replaced.

With the cost of copper and armaflex, it costs a pretty penny to replace many line sets.

He is correct period you guys want to change out the line set for no good reason then have a ball if the line set is the correct size and in good condition no need for replacement. A hand full of mfg's want rx-11 they go back and forth on it.

[tedkidd]

When is it not a burnout?

The truth is that when the system finally has issues, there is no way to prove that a contaminated line set 5 years in the past was the culprit.

Nicely put, seems obvious to me. But maybe ask the homeowner if they want to save 5% on the install. That way you avoid the potential accusation you are replacing things unnecessarily.

Shoul you offer to reuse the coil?

[dash]

We have been installing Puron/R410a replacemenet systems since the late 1990's,hundreds per year.

We have seen Carriers report on our 10 year parts and labor warranties.

The regional service guys comment,you must install well,as that's a very low compressor failure rate.

Follow Davo's advice and you'll be fine guys.

And if you think txv failures are high ,and they have been,it's due to a component mfrs. issue,nothing to do with linesets or mineral oil.

[crmont]

You guys can take your chances all you want. More power to you. When I replace the line, I know that it's clean and has no unseen questionable welds.

No manufacturer is going to question it.

When we all took the 410 training we were instructed on the proper procedure for retrofit.

410 systems (to my surprise) have enjoyed a much lower failure rate because guys have simply followed proper practices that we should have always been using anyway.

Now the trend is "it's not as critical as once thought....."

That's a shame. Now field installations will be open to the interpretation of the installer who may spend 2 or 3 years at any one company.

It's because of the installers who need clear instruction that I feel that it's a mistake to make such a gray area in this matter.

[dash]

Thousands installed,no issue.

To be fair , soft solder was never used in this area ,other then that, no issues,and it's a competitive market.

Linesets aren't in basements here, and are an unneeded expense.

[crmont]

Thousands installed,no issue.


What do you mean "no issue"?

How would any failure ever be acknowledged to have failed because of reuse of the old line set?

You could never prove one way or another, right?

It's a moot point.

[dash]

What do you mean "no issue"?

How would any failure ever be acknowledged to have failed because of reuse of the old line set?

You could never prove one way or another, right?

It's a moot point.

So you are right, no issues.

What issues would you expect,don't say none since you charge to change the linset,which We say is a waste of the consumers money!!

[tedkidd]

Ok, this seems to have reasonable positions on both sides. My take is if in basement (Ie easy) switch, if not, flush.

Anyone not already given their 2c have something to add?

[crmont]

So you are right, no issues.

What issues would you expect,don't say none since you charge to change the linset,which We say is a waste of the consumers money!!

NONE :D if the line set got replaced. Zip, zero, nada...

We don't even offer an alternative. No one else in my neck of the woods does ether.

You have to remember that customers can double check everything that is in the bid on the internet.

Most consumer sites on the internet still recommend the line set replacement. An educated consumer understands the ramifications. It's their house and they don't want to take chances.

This is an endless discussion so I say we're both right.

[crmont]

Ok, this seems to have reasonable positions on both sides. My take is if in basement (Ie easy) switch, if not, flush.

Anyone not already given their 2c have something to add?

Your energy calculator is too cool.

Insulate, smaller hvac, longer cycles. Good resource, Thanks!

[Learn-never-end]

Here ya go, as I read it is not required which means that will become the standard. The mixing of oils is not near the problem that was originally thought ( that comes from our Trane FSR).



from PDF file

While replacing the refrigerant line sets with a new system is ideal;
it’s not always practical, and often impossible.

*Existing line sets must be properly sized
for the new system.


2 statements above -

1. replace if you can, if not

2. flush it and use old line sets provided that line sets properly sized

[crmont]

from PDF file

While replacing the refrigerant line sets with a new system is ideal;
it’s not always practical, and often impossible.

*Existing line sets must be properly sized
for the new system.


2 statements above -

1. replace if you can, if not

2. flush it and use old line sets provided that line sets properly sized

See? Typical HO. Can't hide from the informed...:D

[dan sw fl]

Ok, this seems to have reasonable positions on both sides. My take is if in basement (Ie easy) switch, if not, flush.

Anyone not already given their 2c have something to add?

I don't see any validity to Energy Calc without use of Heating Degree Days.

Heating Degree Days might range from 100 to 8,000 in the U.S.

I don't have a Zero Energy Home just because I use almost No Energy for heating. Some years I simply DO NOT USE my strip heating.
The exception is obviously this year.
In a normal year in SW FL, one can easily count the number of HOURS less than 40'F by paying attention for a FEW days.

[Special Ed]

we don't replace every single lineset - sometimes it's just not easy or possible to do so. So we don't; instead, we flush & we flush well. Flushing includes using Rx-11 flush followed up by a good nitrogen purge & a deep vacuum (sometimes the installers forget the vacuum pump is on there & leave it running sometimes for over an hour).

I know mfg.'s don't recommend this or that, & it has always been that way. Sometimes it's because they don't make a certain product other times it's because they have an in-house product they would rather you use claiming it's the only product authorized to be used with their systems (Ford claims their engines run best on BP/Amoco gas, but we all know gas is gas no matter who makes it!).

My opinion is it's always best to replace the lineset if the HO approves it & if it's possible; if not, I flush. I feel it's the best & right thing to do.

[Home&Marine]

When we all took the 410 training we were instructed on the proper procedure for retrofit.

Who's Official Training did you take?

When you Service Your Car, Truck, Airplane, Motorcycle or Boat do you Follow the Manufacturers Recommendations or the Oil (air-filter, etc) Manufacturers Recommendations? I can tell you who's I follow. ;)

If the Manufacturer Warranties the System Using the R-22 lines (which are the correct size for 410) what's the problem? From what I've read most manufacturers do not recommend flushing, just blow them out with Nitrogen. If Manufacturer knew there was a Problem, don't you think they'd say "Old Line Set Can Not Be Reused With Our 410a Systems or... ". (In Many cases it's impossible to change the line-set.) The residue left in the line is OIL, it can be flushed out very easily.

With the amount of "hacks" as I see in my area, I can promise you if the MFG said "Change The Line-Sets" they wouldn't do it anyway (and I doubt they blow them out with Nitrogen, since some don't use it) much less add a suction line dryer.

I don't know if any of you have heard this one (or used it) but an older Tech I know uses Alcohol for flush, then blows it clear with Nitrogen.

[crmont]

Who's Official Training did you take?


The manufacturers training. I sat through the same damn class 4-5 times I bet.

I give. Your right, I'm wrong.

What about trusting the integrity of the existing line?

Some will look at these pics and get it; some---not so much....

[dash]

NONE :D if the line set got replaced. Zip, zero, nada...

We don't even offer an alternative. No one else in my neck of the woods does ether.

You have to remember that customers can double check everything that is in the bid on the internet.

Most consumer sites on the internet still recommend the line set replacement. An educated consumer understands the ramifications. It's their house and they don't want to take chances.

This is an endless discussion so I say we're both right.

It's a choice.

Can't say consumers are wanting them changed,we sell hundreds per year,lose some sales ,but never heard of lineset being the reason.

May not be a green thing to do,millions of 410a changeouts this year,is a lot of copper.

[davo]

The manufacturers training. I sat through the same damn class 4-5 times I bet.


I give. Your right, I'm wrong.

What about trusting the integrity of the existing line?

Some will look at these pics and get it; some---not so much....

I'm glad you sat through the class 4 times.
What do those pictures prove about integrity of the line set?
Obviously, If you have reason to suspect a faulty line set it should be replaced, r-22 or r-410a. I can tell you, in our area, where units run in a/c mode 2800-3100 hrs a year, if you see a 15-20 year old system, with the origional compressor, chances are there is no major defect in the piping. If they say they had refrigerant added every year, I leak test the equipment. If no leaks found, I recommend replacing the line set. It is not cut or dry. That is my point.
Some of us were installing this equipment before there was a class to go to. Some of us taught the class. Some of us helped come up with the guidlines used by several manufacturers.
Some of us have had to do refrigerant conversions on refrigeration equipment, using the same compressor, condensor and evap, where we had to replace the oil several times to get the dillusion ratio of mineral to AB or POE correct.

I know what might happen. I can also tell you with high temp systems, the POE/mineral oil miscability problem is not that bad. I don't know of any failures due to this. I'm sure there is some out there, but I'll bet there were piping deficiencies or installation deficiencies too.

I will not say I have never changed a line set.
I did not say manufacturers recommend not changing the line sets, I said they don't recommend it.
Someone put a link to rheem saying the contrary, and I was wrong in the phrasing of that statement.
I should have said "manufacturers don't require it."

The fact remains, no one voids warranty, and Companies like Lennox and Carrier have over 15 years track record. I trust Carriers guidlines as they have more R-410a equipment out there then all others combined.

I just take offense when people make short sighted judgement statements, call people hacks, or say they are full of bs, without all the facts.

The fact is, I give our customers the choice, and if they want it, we replace them. I give them our experience on leaving the old ones, and they hardly ever ask us to replace them.

As far as integrity of the line set, in over 15 years, and thousands of installs, we have NEVER had an existing line set fail, unless it was an underground condo application. (1 x in 15 years)
I have had people drive nails, screws, cut with gardening equipment and out right destroy line sets. This is not the refrigerants fault.
Then we have to get approval from the condo association because it requires running through other peoples closets, attics, fire penetrations, and a line cover out side.

These leaks would have happened with r-22 as well, r-410a just sped it up a little.

The bottom line, we stand behind our installs.
If there was ever to be a line set failure within the first year, I put it in writing that I will replace it for an agreed amount.
Never had to replace one yet.
Once we fix the piping deficiencies, they never fail again.

I am asked by a major manufacturer to go out to many sights where repetative compressor failures occur.
I usually find the culprit to be poor piping practices. Not even wrong sizes.
One size too small or too large pipe size generally will not kill a compressor under normal conditions, if proper piping practices were followed.
Couple wrong size and bad practices, on any type system, and you have failure.

[crmont]

I'm glad you sat through the class 4 times.

Every manufacturer required it at the time.

What do those pictures prove about integrity of the line set?

If they will run the lineset like that then they could also have splices under the house or even gravel in the lines, could be any number of things.

If they say they had refrigerant added every year, I leak test the equipment. If no leaks found, I recommend replacing the line set. It is not cut or dry. That is my point.

Usually cheaper to replace the line.. but I am from an area with mostly crawl spaces and attics. VERY FEW linesets are unable to be replaced.


I know what might happen. I can also tell you with high temp systems, the POE/mineral oil miscability problem is not that bad. I don't know of any failures due to this. I'm sure there is some out there, but I'll bet there were piping deficiencies or installation deficiencies too.

Like I said, no way to prove it anyway.

I will not say I have never changed a line set.
I did not say manufacturers recommend not changing the line sets, I said they don't recommend it.
Someone put a link to rheem saying the contrary, and I was wrong in the phrasing of that statement.
I should have said "manufacturers don't require it."

ok.

I just take offense when people make short sighted judgement statements, call people hacks, or say they are full of bs, without all the facts.

Mutual.

The fact is, I give our customers the choice, and if they want it, we replace them. I give them our experience on leaving the old ones, and they hardly ever ask us to replace them.

You are the experts afer all.

As far as integrity of the line set, in over 15 years, and thousands of installs, we have NEVER had an existing line set fail, unless it was an underground condo application. (1 x in 15 years)
I have had people drive nails, screws, cut with gardening equipment and out right destroy line sets. This is not the refrigerants fault.
Then we have to get approval from the condo association because it requires running through other peoples closets, attics, fire penetrations, and a line cover out side.

I definitely see your point. I would do the same in those situations.

These leaks would have happened with r-22 as well, r-410a just sped it up a little.

Definitely.




We're on the same page here. I don't do that many condos. I see your points. All valid. I didn't mean to annoy but I seem to have that gift..:whistle: