Central AC Repair Questions

[tjpavlov]

Here's my situation. I bought a new home ten years ago. It has two forced hot air furnaces (95% efficient) and York condensers and coils. About a year ago I noticed that mice had nested in one of the outdoor condensers and chewed through most of the wiring.

I have an HVAC company that has done work for me before and I've always found them to be competent and honest. The guy rewired things, changed out the capacitors and had to add refrigerant. There may be some more parts that were changed, but I don't remember. He may have replaced the capacitors on the other unit too. The bill was around $700. He told me that the indoor coil was likely starting to leak and that the refrigerant that he added might get me through the summer. But he warned me that I would likely need a coil within a year or two. He said that there was basically a bad design on these York coils and they all fail within 5-10 years.

We had a warm day so I fired up the system this week and ran the AC for about fifteen minutes. It blows, but not cold.

I called the HVAC company up and they came out. There was no refrigerant in the system. The condenser holds pressure as does the line set. So we know that its the coil in the attic which is leaking like a sieve. He gave me two options:

1. Replace just the coil. He said that he could replace it with another York. It would probably be an aluminum one.

2. Replace coil and condenser with a Heil or Rheem. He said that with the condenser having been run dry and being ten years old and being a York, he would encourage me to just change it out too. He said that it would be better to have a matched set.

I don't have pricing yet. They are supposed to be drawing up some numbers for me. I searched online and it does seem like these York systems are problematic. There have been a bunch of class action lawsuits on them. And I know that many of my neighbors have had to replace coils already.

My builder isn't going to be any help.

My other AC coil in the basement and condenser haven't given me any trouble yet. They are slightly smaller systems so hopefully they are from a better run.

So my question to all of you is does this make sense? Should I replace just the coil, or do both the condenser and the coil? I'm not really looking forward to this bill, but my spending is way down over the last few months so I am in a good position to throw some money at this if it gets me a long-term solution.

 

[Jim greengo]

I'd start with a new 410a coil,that way you're atleast ahead of the game.
It doesnt have to be a York brand coil.

 

[Mike007]

He said that there was basically a bad design on these York coils and they all fail within 5-10 years.

That's putting it mildly. York was a good solid product up until roughly 2006 when they were bought by Johnson Controls. The downturn in quality was unbelievable. I wouldn't put a York in my home if it was given to me.

The system is 10 years old, you've been very lucky. If the outdoor coil is aluminum, I wouldn't invest much into it. Throw some refrigerant into it until you are ready, then replace everything. With anything put York. FYI, York is sold under the brand names Coleman, Luxaire, Winchester and others I'm sure.

 

[acmikee]

is your coil copper or aluminum if its copper find the leak and repair it if aluminum it scrap. very few people will be able to solder it

 

[brewchief]

is your coil copper or aluminum if its copper find the leak and repair it if aluminum it scrap. very few people will be able to solder it

Fixing a copper coil from that era is practically impossible, they are leaking in the middle of a tube as often as anywhere else, the processes used when making them means they ended up with super thin tube that was very susceptible to multiple pinhole leaks.

10 year old York? Replace everything, as said above York used to be decent, they then got bought out and started to win the race to the bottom.

Replace the failed system now and start planning for replacement on the second, you might get a couple more years or a couple more months.

Sent from my SM-G965U using Tapatalk

 

[yeldogt]

That's putting it mildly. York was a good solid product up until roughly 2006 when they were bought by Johnson Controls. The downturn in quality was unbelievable. I wouldn't put a York in my home if it was given to me.

The system is 10 years old, you've been very lucky. If the outdoor coil is aluminum, I wouldn't invest much into it. Throw some refrigerant into it until you are ready, then replace everything. With anything put York. FYI, York is sold under the brand names Coleman, Luxaire, Winchester and others I'm sure.

We had York systems growing up in the 60's and 70's and I put them in all my rehabs in the 80's and early 90's. I even moved a couple when I did extensive rehabs on personal properties and the units would work in one of the rehabs to rentals. Many are still running ... tanks. I had a 4 ton unit that I moved in 93 and it was 7 years old then -- I hated to see it go when I remodeled the place 4 years ago. Never touched it ... and it was quiet.

It's a shame --

 

[acmikee]

Fixing a copper coil from that era is practically impossible, they are leaking in the middle of a tube as often as anywhere else, the processes used when making them means they ended up with super thin tube that was very susceptible to multiple pinhole leaks.

10 year old York? Replace everything, as said above York used to be decent, they then got bought out and started to win the race to the bottom.

Replace the failed system now and start planning for replacement on the second, you might get a couple more years or a couple more months.

Sent from my SM-G965U using Tapatalk

most apprentices can fix a copper coil and most leaks are not in the middle of the coil they are on the u tubes

 

[tjpavlov]

Okay, just received the quote. To go to a 16 Seer Ruud/Rheem system, including replacing the outdoor condenser and the coil the quote came in at $5400. That includes $500 of ductwork and 2k of labor

That is more than I expected. Does this seem reasonable to you guys?

 

[brewchief]

most apprentices can fix a copper coil and most leaks are not in the middle of the coil they are on the u tubes

In the past I would have agreed but in recent years we have been seeing a lot of indoor coil failures that are in the middle of the coil. Electronic detector will show presence of refrigerant in the plenum but you can search every end tube joint and not find a leak, replace the coil and leak is solved. Take the old coil and cap it and pressurize it to 400 psi and leave it in a sink full of water and you might get a few very very tiny bubbles from somewhere in the middle of the damn thing.

We probably run into this 10-15 times a summer, we will back up the manufacturers parts warranty with labor if the customer does annual maintenance so lots of our customers are getting 10 years parts and 10 years labor so it has cost us a lot in labor( and refrigerant) to replace leaky coils, it's also something that you don't want to miss a leak somewhere else because you will be back again working for free.

Lennox has moved away from the copper coils to aluminum, I have yet to have a failed aluminum coil.

Sent from my SM-G965U using Tapatalk

 

[Mike007]

most apprentices can fix a copper coil and most leaks are not in the middle of the coil they are on the u tubes

You are not fixing these modern copper coils. It's formicary corrosion. When this issue first showed up with the York coils, I did a lot of head scratching. A coil that would hold 300 PSI N2 indefinitely at room temperature would leak like a sieve when in service.

I wanted to see it for myself. So I threw a coil charged with N2 in a tank of ice water. It held for about 10 seconds and started to slowly bubble. In a minute the coil was literally leaking from everywhere within the tube sheets. Dozens and dozens of tiny streams of bubbles.

 

[yeldogt]

You are not fixing these modern copper coils. It's formicary corrosion. When this issue first showed up with the York coils, I did a lot of head scratching. A coil that would hold 300 PSI N2 indefinitely at room temperature would leak like a sieve when in service.

I wanted to see it for myself. So I threw a coil charged with N2 in a tank of ice water. It held for about 10 seconds and started to slowly bubble. In a minute the coil was literally leaking from everywhere within the tube sheets. Dozens and dozens of tiny streams of bubbles.

That's interesting .....

The quest for efficiencies .. thin tubing walls.

I guess if any acid situation -- that's the end

 

[tjpavlov]

You are not fixing these modern copper coils. It's formicary corrosion. When this issue first showed up with the York coils, I did a lot of head scratching. A coil that would hold 300 PSI N2 indefinitely at room temperature would leak like a sieve when in service.

I wanted to see it for myself. So I threw a coil charged with N2 in a tank of ice water. It held for about 10 seconds and started to slowly bubble. In a minute the coil was literally leaking from everywhere within the tube sheets. Dozens and dozens of tiny streams of bubbles.

So one thing that the tech said is that the total leak is massive. I think he pressurized it to 300lbs and it fell to 250 within minutes. But you can’t hear the leak at all. It’s likely that there are many, many tiny holes.

What is everyone’s opinion on my path forward? Should I replace just the coil or go all in and do the condenser outside too?

 

[yeldogt]

What was his cost to just do the coil?

Is the furnace a single speed ? In the attic ..conditioned space?

What's the rebate -- energy programs in RI?

Here is the deal IMO. Unless you have high cooling loads most times the higher efficiency equipment has a long payback -- you most likely have around 13 SEER system. What do you gain by replacing basically same with same.

Where it makes a difference -- especially in a humid place like RI is when you step up to VS equipment with more than one speed. Then you get not only some savings -- but you get comfort. That's the big deal with the new modern equipment -- comfort.

So you replace the AC on a 10 year old furnace .. that locks you in if the furnace goes in 4 years. At $5400 -- that's .. $500 a year for 10 years. If you get 3 years out of the new coil at $1500 .. same thing. Understand ?

Look into rebates and replace the whole thing down the line ...

 

[tjpavlov]

Yes the furnace is a standard 95% efficiency single speed model. The attic is unconditioned but will probably be finished at some point. Probably looking at a dual head minisplit for that project. He did mention that the current furnace has a lifetime guarantee on the heat exchanger which may be part of the reason he’s not pushing me to replace that.

The contractor quoted me out a 13 seer system. It only saves me about $500 and I would get about that in tax credits and rebates if I bought the 16 seer. So the 16 seer it is.

I don’t have a formal quote on just doing the indoor coil. I think it would be around $1,700 to do.

Thanks for all the thoughts and advice.

 

[yeldogt]

Yes the furnace is a standard 95% efficiency single speed model. The attic is unconditioned but will probably be finished at some point. Probably looking at a dual head minisplit for that project. He did mention that the current furnace has a lifetime guarantee on the heat exchanger which may be part of the reason he’s not pushing me to replace that.

The contractor quoted me out a 13 seer system. It only saves me about $500 and I would get about that in tax credits and rebates if I bought the 16 seer. So the 16 seer it is.

I don’t have a formal quote on just doing the indoor coil. I think it would be around $1,700 to do.

Thanks for all the thoughts and advice.

I was saying the current system is around 13 -- not the new one. I was trying to show what the saving is.

Does RI have any energy programs? Some states have energy audits and all kinds of grants and programs ... but you have to replace whole system.

The heat exchanger being lifetime does not typically cover labor -- you end up being in the same boat. Fix a 15 year old heater or replace.

My question about the unit and attic -- is where is the unit located. Are both systems in the basement or is one in the attic ?

 

[tjpavlov]

The system that isn’t working is for the upstairs. The furnace is in the attic. The system that heats and cools the first floor is located in the basement.

If I go with a 16 seer system I get about $450 in rebates. That covers the cost of stepping up to 16 from 13. I think the current system is 13 seers.

Rebates are available for furnaces. I could get around $1250 back on a furnace if I went all the way up to a modulating unit with 98% efficiency.

 

[SGKent]

Okay, just received the quote. To go to a 16 Seer Ruud/Rheem system, including replacing the outdoor condenser and the coil the quote came in at $5400. That includes $500 of ductwork and 2k of labor

That is more than I expected. Does this seem reasonable to you guys?

what is the tonnage on the unit and how large is the house. How old is the house? Is this unit part of a furnace or is it a separate system?

My instinct tells me that the price may be reasonable depending on the questions above, you don't want to wait until it is 95F outside every day.

 

[tjpavlov]

what is the tonnage on the unit and how large is the house. How old is the house? Is this unit part of a furnace or is it a separate system?

My instinct tells me that the price may be reasonable depending on the questions above, you don't want to wait until it is 95F outside every day.

The house is ten years old. The A.C. is a three ton unit. It cools about 1400 square feet. And yes, it is attached to a forced hot air system

 

[danski0224]

I'm really curious to know how the condenser and line set were isolated not only fron each other but also from the evaporator coil to determine that they held pressure.

 

[JerryC]

Okay, just received the quote. To go to a 16 Seer Ruud/Rheem system, including replacing the outdoor condenser and the coil the quote came in at $5400. That includes $500 of ductwork and 2k of labor

That is more than I expected. Does this seem reasonable to you guys?

For reference my house was built in 95 and had two York systems. One of them went 21 years before the AC started to leak and was totally shot two summers later. The furnace lasted 23 years. I replaced the system as one after 19 years while running window AC's for two years and no furnace for a year. It wasn't fun, but we didn't have the money. The other AC went out after just 8 years and we replaced the system at that time with a slightly larger setup 3.5 ton - 4 ton. Again, a York with the now infamous "micro-channel" design. That AC lasted 14 years but leaked for several years and needed several pounds of refrigerant each year. The furnace ran like a top until we replaced the systems and actually we heated the whole house off that furnace for a full winter.

It sounds like your guy knows what he is doing and is looking out for you.

Prices can be regional, but I suspect that they vary widely all around the US.
I had both systems for downstairs and upstairs, furnace, coil and condenser, replaced for 9K last year. 13 Seer Rheem, 2.5 ton and 4 ton. I had three quotes two that were fairly close and one that was 22K!!!

The equipment was not the big difference in cost, it was the size and advertising of the companies. The two small companies were close and the big company with all the trucks and non-stop TV and radio ads had the crazy price. They all quoted 13 seer systems, oh and that 22K quote included two FREE furnaces, yeah right...

It took about seven hours for a 3 man crew to do the job, including a lunch break. Both furnaces are in the walk-in attic next to each other and the condensers are next to each other as well.

 

[samss]

Does your condensing unit have a low pressure switch to prevent the compressor from running if the refrigerant has leaked out?
Yes = replace evaporator coil.
No = replace everything.
A flat system will pull in air/moisture if the compressor continues to run. POE oil is hygroscopic. Even changing the oil, pain in the rear sometimes, doesn't ensure a healthy compressor.

 

[yatg]

If you're switching from R22 to R410a, you should replace everything, R410a uses higher pressures than R22. Evaporator, condenser, compressor. Lineset too if you can get at it, otherwise make sure they flush and dry the lineset.

Had a 5 ton York on my last house. Lasted from 93 to 2017. Back in the late 2000s it stopped cooling, called out a well known AC company and he said "its dead you need to replace the whole thing". Quote was over $6K back then. Did some research then called them back out and bitched and had them come back out to add refrigerant. Ran another few years without an issue, then I had to add a can or so every year to keep it going until it finally died.

Point is that some HVAC companies prey on your lack of knowledge. And probably the field tech gets a bonus for every new system he sells. Never called that company again and made sure to tell people about their tactics. If they would have been honest from the start, I would have kept doing business with them and recommended them.

 

[yeldogt]

The system that isn’t working is for the upstairs. The furnace is in the attic. The system that heats and cools the first floor is located in the basement.

If I go with a 16 seer system I get about $450 in rebates. That covers the cost of stepping up to 16 from 13. I think the current system is 13 seers.

Rebates are available for furnaces. I could get around $1250 back on a furnace if I went all the way up to a modulating unit with 98% efficiency.

My point with the SEER -- is to discuss what savings you will have in electric with the with new system vs what you will pay currently. With most people the small increase will not be very much. I'm not talking about if you should install another 13 -- with rebates that never is a practical option. 13 is the lowest now allowed and almost everywhere the rebates make going higher worth while.

You are doing like for like -- the new system is going to do what the old system did .. with a tiny saving and $5400 spent.

What you need to think about is what is going on in the attic -- is the current system within the building envelope? How is the attic insulated ? What is going to happen when you fix up the attic and turn it into living space .. can the system in the attic take care of that new space.

With todays VS equipment and zoning -- lots of possibilities.

Putting in a new system w/o thinking about the above is foolish IMO -- I like mini-splits ... they are great problem solvers and I'm using a muti-head in my new build. But -- I'm also using a three zone conventional ducted in the main building. I can't do a ducted in my addition due to space.

You could easily spend 8-10k in a few years putting mini splits in ...

Sometimes it's best to evaluate the whole thing and see what best for the future.

 

[tjpavlov]

I'm really curious to know how the condenser and line set were isolated not only fron each other but also from the evaporator coil to determine that they held pressure.

I try not to hover over contractors when they are working because I think that I sometimes annoy them with my questions. But really I am usually just curious as to how all of this stuff works. Here is my understanding of the diagnosis:

First, he cut the lineset at the outdoor condenser and ran a pressure test. It showed a leak somewhere in the lineset or the coil. I am trying to avoid replacing the lineset. It runs through the basement, up through the house and into the attic. We would have to abandon it and run a new one on the exterior of the house. Due to the way that the house is positioned, it would be very noticeable.

Second step was he clipped the lineset in the attic, just before the coil. I think that he soldered it shut and re-ran the pressure test from outside. He left the gauges on overnight and it held pressure. So we concluded that the leak is in the coil.

 

[tjpavlov]

For reference my house was built in 95 and had two York systems. One of them went 21 years before the AC started to leak and was totally shot two summers later. The furnace lasted 23 years. I replaced the system as one after 19 years while running window AC's for two years and no furnace for a year. It wasn't fun, but we didn't have the money. The other AC went out after just 8 years and we replaced the system at that time with a slightly larger setup 3.5 ton - 4 ton. Again, a York with the now infamous "micro-channel" design. That AC lasted 14 years but leaked for several years and needed several pounds of refrigerant each year. The furnace ran like a top until we replaced the systems and actually we heated the whole house off that furnace for a full winter.

It sounds like your guy knows what he is doing and is looking out for you.

Prices can be regional, but I suspect that they vary widely all around the US.
I had both systems for downstairs and upstairs, furnace, coil and condenser, replaced for 9K last year. 13 Seer Rheem, 2.5 ton and 4 ton. I had three quotes two that were fairly close and one that was 22K!!!

The equipment was not the big difference in cost, it was the size and advertising of the companies. The two small companies were close and the big company with all the trucks and non-stop TV and radio ads had the crazy price. They all quoted 13 seer systems, oh and that 22K quote included two FREE furnaces, yeah right...

It took about seven hours for a 3 man crew to do the job, including a lunch break. Both furnaces are in the walk-in attic next to each other and the condensers are next to each other as well.

Thanks for sharing your thoughts, especially on the amount of labor. The company doing the job is a small, family-owned outfit. It's a father and two sons. One of the sons is a friend of a friend. I trust them. They've worked for me before and I've never really had a problem. I'm also at a point in my life where I value service more and more. I'm not worried about saving $100 by shopping around. I just want to verify that their recommendations sound reasonable and that the price isn't outrageous. Kind of a trust, but verify situation.

 

[tjpavlov]

Does your condensing unit have a low pressure switch to prevent the compressor from running if the refrigerant has leaked out?
Yes = replace evaporator coil.
No = replace everything.
A flat system will pull in air/moisture if the compressor continues to run. POE oil is hygroscopic. Even changing the oil, pain in the rear sometimes, doesn't ensure a healthy compressor.

I am thinking that it doesn't. I ran it for about fifteen minutes with no refrigerant. The tech said that it may be damaged because the refrigerant also acts as a lubricant.

 

[tjpavlov]

My point with the SEER -- is to discuss what savings you will have in electric with the with new system vs what you will pay currently. With most people the small increase will not be very much. I'm not talking about if you should install another 13 -- with rebates that never is a practical option. 13 is the lowest now allowed and almost everywhere the rebates make going higher worth while.

You are doing like for like -- the new system is going to do what the old system did .. with a tiny saving and $5400 spent.

What you need to think about is what is going on in the attic -- is the current system within the building envelope? How is the attic insulated ? What is going to happen when you fix up the attic and turn it into living space .. can the system in the attic take care of that new space.

With todays VS equipment and zoning -- lots of possibilities.

Putting in a new system w/o thinking about the above is foolish IMO -- I like mini-splits ... they are great problem solvers and I'm using a muti-head in my new build. But -- I'm also using a three zone conventional ducted in the main building. I can't do a ducted in my addition due to space.

You could easily spend 8-10k in a few years putting mini splits in ...

Sometimes it's best to evaluate the whole thing and see what best for the future.

I am very sympathetic to your thinking on this. If he had just wanted to throw in a new coil for $1,700 I would have just done it. But now we are talking about a significantly more expensive job. I asked about whether he thought we should just upgrade the furnace, but he said that there really wasn't a need. I am going to call on Monday and try to get a sense of how much more it would cost to move to a variable speed model.

So the attic is not conditioned. It's fully vented at the ridge and soffit. I would say that finishing the attic is somewhere between 3 and 8 years away. Doing so would add about 900 square feet of space due to the slope of the ceiling (10 pitch roof). I have considered spray foaming the underside of the roof and changing to an unvented space, but I don't know. I got a quote for that and it was like $8,000. To leave if vented, add baffles and rockwool/fiberglass would be way cheaper. I'm just not sure the value is there on foaming it. Regardless of what I use for insulation, I will move the furnace inside the conditioned space. the ductwork would likely have large parts in the unconditioned space if we went with rockwool/fiberglass though.

I talked to the tech about the option of changing the furnace to something that could be zoned later for the upstairs. He said that he would still recommend a mini-split for the attic though. He said that the cost of adding all of the zone dampers later and new ductwork wouldn't be that far off the cost of the mini-split. He also said that the mini-split would do a much better job of cooling the attic when the time came.

 

[tjpavlov]

I just want to say thank you to everyone for sharing their thoughts and opinions on this. I am in a little bit over my head!

 

[LS6 Tommy]

most apprentices can fix a copper coil and most leaks are not in the middle of the coil they are on the u tubes

X2. The only leaks on the face of a coil I've ever seen were on hydronic heating coils that froze.

BTW, how did they isolate the evaporator coil to leak check the line set? There's no service valves on the evaporator. If they isolated the condensing unit and pressurized the line set and it held, there's no leak in the evaporator either...

Tommy

 

[yeldogt]

I can see why you trust them -- that's no "you need a new AC" .... fly by ...look see. They checked and isolated the problem.

I would not spend to replace the heater either -- it's all money spent getting the same thing. Like replacing the water pump on your car ...

I can tell you this -- done properly - you will never regret foaming the attic. You will be shocked at the comfort increase -- the load on the HVAC will drop and the unit will not be exposed to the outside temps. Win/win/win. And when you do fix up the attic -- The load increase will be a fraction of what it would be. A foamed space can easily ... easily, be done with 1T per 1K sf.

I would ask again about the fix .... explain the whole situation. They sound like decent people ... they would be best to answer.

I do zoned systems .. so I'm biased. But - mini splits are great as well.

 

[SGKent]

to me after hearing the whole story I would replace the full system including the heater. I would want the units that are known for the least problems. Before doing a replacement would ask the HVAC folks to run a pressure test on both the inlet and outlet side of the with the fan running at proper speeds. I'd do so using the filters you plan to run the system with. The best system in the world isn't going to work at full efficiency, or last as long if the filter inlet(s) and ducting are undersized. Currently the 3M Filtrete 1900 are the best filter / pressure loss combination excepting the horsehair and fiberglass filters designed to stop the cat from wandering in.

 

[tjpavlov]

Just wanted to check in to let everyone know how things turned out for me. I wound up replacing the entire AC system with a 16 SEER system. The new outdoor condenser is massive! Went with the Rheem/Ruud system based on the HVAC company's advice. Although it is much bigger, it is considerably quieter than the condenser it replaced.

Thanks to everyone who chimed in with their thoughts and advice. It was a great help to read through everything and help me hone in on the right decision for my family.

 

[Mike007]

Compared to other equipment made today, Rheem/Ruud equipment is very good. And as a company they seem to stand behind their equipment and actually acknowledge issues, don't deny them. Absolutely make sure you register the equipment and keep the documentation for the 10 year parts warranty. Don't rely on the contractor to do it.

 

[Rusty Fords]

Quote" The condenser holds pressure as does the line set. So we know that its the coil in the attic which is leaking like a sieve. "

Did the tech pull out his torch and sell the line set at the indoor coil?
If its leaking like a "sieve" it should be easy to locate the leak and get an idea of whether its a tube sheet or something else!!

I've fixed a lot of leaks on indoor coils very few in the tube sheets except on very old commercial/industrial equipment.
U bends is the most common and some times the little tubes that come off the distributor rub together and get holes all of which are very easy to repair pull your heat way back and let the tips of the flame do the work.

I'd repair but it is always a gamble.

 

[Rusty Fords]

Sorry didn't realize there was a second page tel after I posted. Good luck