[TimSBLI]

I am getting estimates for replacing my 4 ton hvac system. The old system is r-22 and leaking so I am going to a new system with r410a. I am pricing units from 13 seer to 16 seer leaning toward 16 seer. I am having it proffessionaly installed.
One of the 16 seer options calls for 220v at the air handler. I am comfortable with doing the wiring myself, I ran the wire to the existing air handler and condenser when they were first installed. I haven't gotten any model numbers yet so I can't see for sure the amperage that it draws or the breaker. most models seem to use 15 amp two pole breaker. Does that sound about right.- of course I will check the pdf- just trying to get an idea for price wise since I have plenty of 12/3 laying around. Also what kind of disconnect at the air handler would I use - same type as the one outside at the condenser? Any recommendations on 16 seer Rheem/Rhuud units? Any problem reusing the existing 15 year old line set assuming it is sized and flushed properly?

 

[roughneck]

Will this be a heat pump?

 

[supers05]

If it's easy to access, replace the lineset. If not, then it is what it is. I've reused linesets before, but it's definitely not ideal.

What kind of heat is going in the air handler? (if this is a heat pump, then it's called backup heat) If NG or otherwise no heat strips, then 15A. At least 25A for a 5kW element, 50A for a 10kW, etc.

Cheers!

 

[TimSBLI]

No heat pump, I'm Long island, NY. I use Ac May/June-Sept. I'll probably replace the line set but the budget is tight and I'd rather spend it on efficiency. We have some of the highest electric rates in the country.

 

[user_12345a]

How are you getting your heat now?

If it's electric elements in the air handler I would strongly recommend a heatpump over a straight cool. (granted, u would be better off pulling the plug on the electric heat if there's gas available)

Even in a cold climate they reduce electric resistance heat use down to 10-15f, resistance heat cutting in and out as needed below 30-40f.

Going from 10 or less to the 13 minimum probably saves a lot.

You don't save much by going high-seer - like moving from 13 to 16+.

13 seer is pretty good - it used to be high efficiency in the 1990s.

You can get a 14, air handler with a variable speed blower and it becomes 15.

Above that you're wasting your money in a mild climate.

Putting 16 to 18+ seer in the northeast is like putting a 95% efficient furnace in phoenix arizona. You'll never get the money back, spend the money on something with a better roi like led light bulbs.

 

[bfletcher7]

No heat pump, I'm Long island, NY.

I'm not a trained specialist; I'm merely a homeowner who came here a few months ago for expert advice like you are today. But from what I've read of others here I have a feeling there are other pros whom would suggest just what 12345 is--a heat pump will work in your climate down to x*. I'm in Southern Ohio and with my 14 SEER HP manufactured in 2007 I use it exclusively down to high single digits. Granted, I forgo temp setbacks when it is extremely cold but I am grateful that I can use my HP over the electric strips for much of my winter heating. Good luck.

 

[yuri]

My company always replaces the lineset unless it is physically impossible. You don't want any leftover mineral oil in a 410 system that uses POE polyester oil. You can flush old lines but it is complex and you need a expensive flush kit or use liquid R22 and recover it.

 

[beenthere]

My company always replaces the lineset unless it is physically impossible. You don't want any leftover mineral oil in a 410 system that uses POE polyester oil. You can flush old lines but it is complex and you need a expensive flush kit or use liquid R22 and recover it.

I seldom change out the line set. I just blow them out with nitrogen. Min and POE mix together well enough that it will circulate both, and not harm the system.

Lots of scare tactics were used by manufacturers when R410A first came out. Which is strange when you consider that POE oil was being used in new compressors for replacing worn out compressors for refrigeration 14 years before R410A was invented.

 

[yuri]

Interesting. As long as a good long proper snort/flush of nitrogen is used it may be OK.

However there is always the small possibility the old mineral oil had some acid/contamination in it. My company is not the cheapest and our customers don't mind paying for the extra copper. We just build it into the quote. Installers get paid piece work and are told to do it.

They loved it when they got to keep the old copper. Now it goes into the Xmas party fund.

 

[bfletcher7]

I'm not intelligent but from pieces of data I've read in the Refrig & AC Tech book, if/when I replace my system I will have the lineset replaced. Oil aside, and perhaps my concern is unfounded, but I believe I have learned there are some whom do not sweep with nitrogen when brazing and I simply would not have peace of mind worrying about the condition of the copper. And if I did not know the entire history of a system I'd worry there could have been a compressor burnout, defective metering device with a damaged screen, etc. where proper measures were not taken to flush--or perhaps even with a flush there could be fragments of contaminants at bends.

 

[BayouRunner]

They loved it when they got to keep the old copper. Now it goes into the Xmas party fund.

We save all ours and take the employees and spouses to The Talledega Nascar races once a year. Have been doing this for about 15 years, they love it.

 

[yuri]

We save all ours and take the employees and spouses to The Talledega Nascar races once a year. Have been doing this for about 15 years, they love it.

Yeah, that is one thing the US has that Canada lacks. Easy access to Nascar. One of my co-workers goes down South for a race every year. Very LOUD from what I hear. Quaker State or someone had a race car on tour where I am and I got to see one at our local Canadian Tire. Not much inside. Like riding in a lawnchair bolted to a steel frame from what I saw.

No cupholder or stereo either. With all those laps I would want both.:biggrin2:

 

[yuri]

I'm not intelligent but from pieces of data I've read in the Refrig & AC Tech book, if/when I replace my system I will have the lineset replaced. Oil aside, and perhaps my concern is unfounded, but I believe I have learned there are some whom do not sweep with nitrogen when brazing and I simply would not have peace of mind worrying about the condition of the copper. And if I did not know the entire history of a system I'd worry there could have been a compressor burnout, defective metering device with a damaged screen, etc. where proper measures were not taken to flush--or perhaps even with a flush there could be fragments of contaminants at bends.

It is a debateable subject with no end. IMO most major contractors who are not having to nickle and dime every $50 out of a quote to get a job for fear of losing it have no problem with replacing the lines.

IMO it is like rebuilding a car engine and using recycled or dirty oil to put back in. I would want all new stuff and my customers do too. If the ceiling is closed and plastered etc we have no choice but 95% of the time we replace them. There are also cases where you need a 3/4" suction line and reusing a 5/8" is not recommended.

We had 95F last week and tomorrow it is going to snow. Weather is up and down like a toilet seat.

Gotta love the Great White North.

 

[BayouRunner]

Yeah, that is one thing the US has that Canada lacks. Easy access to Nascar. One of my co-workers goes down South for a race every year. Very LOUD from what I hear. Quaker State or someone had a race car on tour where I am and I got to see one at our local Canadian Tire. Not much inside. Like riding in a lawnchair bolted to a steel frame from what I saw.

No cupholder or stereo either. With all those laps I would want both.:biggrin2:

LOL on the cupholder. I'm not a big fan, have to many other hobbies, but I do make the one race a year. It's very entertaining. We camp on the infield, we can watch it the roof of the camper, or walk up to the track maybe a hundred yards or so. Live bands and the cookouts are the best. It is a good time for sure