Trey T
Well-known member
Yup all true, but that's not my point. Keep in mind, generally I would pick Goodman over Lennox.
Best Air Conditioner Brand
- Thread starter BleedingBlue
- Start date
nothing really wrong with goodman .. until recently they did not sell a product the could compare with the better stuff. The low line that every hack installed was basic at best .. noisy .. god were some them noisy.
The purchases by Daikin and the new Amana products look impressive for the $$ .. still not there for the controls //zoning .. but I'm sure they will be. They must be confident of the in-house compressors with the warranty they are giving.
Trey T
Well-known member
Generally, it's really hard to keep up with HVAC products in the last 10yrs as manufactures have to modified their design because of the phasing-out the use of chlorinated refrigerants. On top of that, DC inverter technology are flown in from euro/asia that have caused some disruption in the market in the recent years.
... you know ... there's a lot of things changed and will continue to change.
Even the best tech or engineer will not be able to tell you what's best because it's not proven to be reliable in long-term.
... you know ... there's a lot of things changed and will continue to change.
Even the best tech or engineer will not be able to tell you what's best because it's not proven to be reliable in long-term.
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stratoguzzi
Member
My Goodman is noisy...They sell a blanket to install over the compressor,but the fact that it is a packaged unit [everything in one unit] and the duct work is bolted to the house makes it more noisy than it should be.Also it is right outside the bedroom window.Doesn't anybody think when they install these units? But again never had any trouble with it!
ipdaley
Active member
I have worked in Research and Development for three major HVAC manufacturers. The past 19 years as a Design Engineer and have developed many residential split systems. Here are some thoughts I share with anyone that asks the question, “Who builds the best systems?” or “What should I look for in a new system?”:
ALL manufacturers use the same basic design. All have a compressor, outdoor coil, outdoor fan, indoor coil, and some means to move air through the indoor coil. The refrigeration cycle has not changed since Dr. Carrier developed the first air conditioner.
The #1 advice I can give anyone is when purchasing a system, get a MATCHED system. I am NOT saying purchase a system that has an AHRI certificate. What I mean is to make sure all the components are manufactured by the same company. If you buy Trane, get all Trane components. Same goes for Lennox, Carrier, Goodman, York, Rheem, etc. You do NOT want a third-party indoor coil. You would not believe how much time and resources are spent by the OEMs to develop systems. Any manufacturer’s system is going to be most efficient using their components.
SEER… Depending on the region you are in the US, the minimum SEER is 13. At 13 SEER, you CANNOT justify purchasing a higher efficiency system on a cost basis. I am NOT implying not to purchase a high efficiency system. I am just saying the payback period will take years.
SEER… I don’t care about SEER. I do care about EER. Energy Efficiency Ratio: this is the classical definition of efficiency: work output divided by work input. EER = cooling capacity at 95degF divided by the total electrical input. EER is dollars out of your pocket through your power bill. Higher EER = lower power usage. In 2007 I developed a line of condensing units. Target was 16 SEER. The 3.5 ton system came out at 15 SEER and needed to lose 35 watts to hit 16 SEER. Think about that… 35 watts. That is less electricity than a small appliance incandescent light bulb. SEER is a numbers game.
ANY system is only as good as its installer. Split systems are field assembled. The manufacturer has no control over it. Working for OEM manufacturers, I have met many “customers”. That customer is the installer. In most instances, the homeowner may be paying for the system but they rely on the installer. When the unit quits blowing cold and the homeowner calls someone for service, there is a 99% chance that if the system needs replacing the system sold is the brand carried by the installer/service company. I have met technicians that are knowledgeable and truly care about quality installations. I have also met technicians that I would not allow to sweep my driveway. It is a **** shoot.
I could go on but I will stop with this: “What would I put in MY home?” I am a big fan of two-stage systems using an ECM indoor air mover. In second stage, the system might have 11.5 to 12 EER. In first stage (where the system runs 80% of the time) the EER would be 18 or 19. I like ECM air movers because if they are developed properly, they deliver constant CFM regardless of the indoor static pressure. Higher static means more indoor watts BUT you get the cooling capacity you paid for. In addition they can help with poor airflow distribution in some cases.
ALL manufacturers use the same basic design. All have a compressor, outdoor coil, outdoor fan, indoor coil, and some means to move air through the indoor coil. The refrigeration cycle has not changed since Dr. Carrier developed the first air conditioner.
The #1 advice I can give anyone is when purchasing a system, get a MATCHED system. I am NOT saying purchase a system that has an AHRI certificate. What I mean is to make sure all the components are manufactured by the same company. If you buy Trane, get all Trane components. Same goes for Lennox, Carrier, Goodman, York, Rheem, etc. You do NOT want a third-party indoor coil. You would not believe how much time and resources are spent by the OEMs to develop systems. Any manufacturer’s system is going to be most efficient using their components.
SEER… Depending on the region you are in the US, the minimum SEER is 13. At 13 SEER, you CANNOT justify purchasing a higher efficiency system on a cost basis. I am NOT implying not to purchase a high efficiency system. I am just saying the payback period will take years.
SEER… I don’t care about SEER. I do care about EER. Energy Efficiency Ratio: this is the classical definition of efficiency: work output divided by work input. EER = cooling capacity at 95degF divided by the total electrical input. EER is dollars out of your pocket through your power bill. Higher EER = lower power usage. In 2007 I developed a line of condensing units. Target was 16 SEER. The 3.5 ton system came out at 15 SEER and needed to lose 35 watts to hit 16 SEER. Think about that… 35 watts. That is less electricity than a small appliance incandescent light bulb. SEER is a numbers game.
ANY system is only as good as its installer. Split systems are field assembled. The manufacturer has no control over it. Working for OEM manufacturers, I have met many “customers”. That customer is the installer. In most instances, the homeowner may be paying for the system but they rely on the installer. When the unit quits blowing cold and the homeowner calls someone for service, there is a 99% chance that if the system needs replacing the system sold is the brand carried by the installer/service company. I have met technicians that are knowledgeable and truly care about quality installations. I have also met technicians that I would not allow to sweep my driveway. It is a **** shoot.
I could go on but I will stop with this: “What would I put in MY home?” I am a big fan of two-stage systems using an ECM indoor air mover. In second stage, the system might have 11.5 to 12 EER. In first stage (where the system runs 80% of the time) the EER would be 18 or 19. I like ECM air movers because if they are developed properly, they deliver constant CFM regardless of the indoor static pressure. Higher static means more indoor watts BUT you get the cooling capacity you paid for. In addition they can help with poor airflow distribution in some cases.
James-W
Well-known member
We have a Carrier and it has been trouble free for the most part. About 2 months after we got it we had a loud noise from the unit and we called the HVAC company who installed it. The guy came out right away and he replaced something called the "contactor". I wasn't home when he was there and I am not sure what the "contactor" is, but the central air has worked perfectly ever since.
driftpin
Well-known member
Plenty of industry types on here. They do the work, they know what they see, and what works, and what doesn't. I am not an industry person, only a consumer. I can relate my experiences.
One of my friends is a HVAC master license-holder since his mid-20's which means now he's got nearly 40 years as a contractor and more-than that in the business. He works residential almost exclusively.
He recommended another contractor to me as he's ~60 miles from my home. That contractor removed a 1980's split system install, not a big home, <1700 sq. ft. I was paying ~$280 for cooling bills in the summer, August is usually the hottest here in So. FL. I got a Bryant variable-speed which is very quiet, unless you have everything-else off, and go stand under a register, and listen you don't know it's on. It works great, controlling the temp and humidity, no clamminess, and the first August bill came-in at $130, quite a difference. It's a SEER of 19. It was considerably more-expensive than a RHEEM or RUUD, but with the manufacturer's rebate, and the tax break for an efficient unit, plus the difference in my bills compared to my probably 20+ year-old unit, payback difference between a standard system and this was under two years. Well-worth-it.
We have another house, recently remodeled & additions, we were out of it for a year. The same contractor did us a Bryant there, and it's been a great unit, it controls things very well. Also quiet and efficient, SEER is 19, variable-speed, for a ~3,000 sq. ft. house.
MY HVAC friend says Goodman is nothing he would install in his own home, and if someone insists on it because of price, he will install it, but in his experience, they don't last as-long, trouble-free. If something goes-bad, the part may be warrantied, but you still have to pay for the labor. He explains that to the homeowner who insists on Goodman by name for the price. For most consumers, he recommends RHEEM/RUUD.
In these days of social-consciousness, you can choose to vote with your pocket-book. That's one place that I can say I won't buy Goodman. Here's why, the heir to the family fortune lives in Palm Beach County FL, he's a rich man who is alleged to have driven with a BAC of .177, and with oxycodone in his system, when his Bentley hit a recent college graduate's car, causing it to enter a canal, where the young man drowned. Since that time, Goodman has been doing everything he can to avoid jail, instead of admitting his mistake, and paying his due to society. http://www.sun-sentinel.com/local/p...ood-supreme-court-hearing-20170830-story.html He has been successful in avoiding jail for the most part, and I suppose you could say, "why shouldn't he, he's rich, and can afford it." Well, I would never buy a Goodman product because it is well-established through court outcomes that his actions resulted in the death of a promising young man, and Goodman's done all he can to avoid paying his debt to society. He's irresponsible, a criminal whose actions cost someone their life, and I vote with my pocket-book not to purchase Goodman AC products.
One of my friends is a HVAC master license-holder since his mid-20's which means now he's got nearly 40 years as a contractor and more-than that in the business. He works residential almost exclusively.
He recommended another contractor to me as he's ~60 miles from my home. That contractor removed a 1980's split system install, not a big home, <1700 sq. ft. I was paying ~$280 for cooling bills in the summer, August is usually the hottest here in So. FL. I got a Bryant variable-speed which is very quiet, unless you have everything-else off, and go stand under a register, and listen you don't know it's on. It works great, controlling the temp and humidity, no clamminess, and the first August bill came-in at $130, quite a difference. It's a SEER of 19. It was considerably more-expensive than a RHEEM or RUUD, but with the manufacturer's rebate, and the tax break for an efficient unit, plus the difference in my bills compared to my probably 20+ year-old unit, payback difference between a standard system and this was under two years. Well-worth-it.
We have another house, recently remodeled & additions, we were out of it for a year. The same contractor did us a Bryant there, and it's been a great unit, it controls things very well. Also quiet and efficient, SEER is 19, variable-speed, for a ~3,000 sq. ft. house.
MY HVAC friend says Goodman is nothing he would install in his own home, and if someone insists on it because of price, he will install it, but in his experience, they don't last as-long, trouble-free. If something goes-bad, the part may be warrantied, but you still have to pay for the labor. He explains that to the homeowner who insists on Goodman by name for the price. For most consumers, he recommends RHEEM/RUUD.
In these days of social-consciousness, you can choose to vote with your pocket-book. That's one place that I can say I won't buy Goodman. Here's why, the heir to the family fortune lives in Palm Beach County FL, he's a rich man who is alleged to have driven with a BAC of .177, and with oxycodone in his system, when his Bentley hit a recent college graduate's car, causing it to enter a canal, where the young man drowned. Since that time, Goodman has been doing everything he can to avoid jail, instead of admitting his mistake, and paying his due to society. http://www.sun-sentinel.com/local/p...ood-supreme-court-hearing-20170830-story.html He has been successful in avoiding jail for the most part, and I suppose you could say, "why shouldn't he, he's rich, and can afford it." Well, I would never buy a Goodman product because it is well-established through court outcomes that his actions resulted in the death of a promising young man, and Goodman's done all he can to avoid paying his debt to society. He's irresponsible, a criminal whose actions cost someone their life, and I vote with my pocket-book not to purchase Goodman AC products.
ipdaley
Active member
Agree. Replacing the entire system is EXPENSIVE. You do what you have to do to keep cool. I've done the same in the past. I despise the third-party guys. Sure the installer gets to pocket some extra profit but the homeowner pays for that inefficiency for YEARS afterwards.
Bought a house once. New construction. My wife and I found it before the builder was finished but the HVAC was already in place. Had builder grade equipment with third party coil. 4 ton outdoor condensing unit with third party coil. Tiny A-coil on top of the furnace. Moved in. Indoor had that cool/moist feeling (system was short cycling). Did load calcs. I put in a 2.5-ton heat pump and ECM furnace (free equipment... was set up as a "field test" by my boss). What a difference. Told the builder he got screwed by his installer. Even shared my load calculation with him.
It doesn't stop there. about a year or so later I get a call. A friend of the builder liked the floor plan of our house and was building a copy in the same region for himself. Our builder had shared the load calcs with him. Guy said his HVAC installer REFUSED to install a 2.5-ton system on his house. Said the only way he (the installer) would do it was by forcing the guy to sign a affidavit stating the install was as-is with no warranty (installer warranty). Installer said he had been putting in systems for decades and had never seen a system so small on a house that size. He asked my opinion. Told him he was the homeowner and he would have to work it out with whoever he chose to install the system (I did not want in the middle of that fight). All I could tell him was our home was VERY comfortable and I kept indoor temp at 72/74 over the previous summer (that was a unusually hot summer too).
You don't know what you don't know. Most people think "well the old one worked" .. then when you dig a bit deeper ... "well that room or this room was too hot or cold". But, it worked "well enough".
Getting a proper load on the building is so difficult -- it should not be .. but it is. Had the same situation recently w/ one installer who simple did not understand a spray foamed house -- and the smaller requirements. I did a house with 1000sf per ton w/o any issues about 12 years ago ... I know it can work and I'm not about to put a 5T unit in a < 3000sf house. Also -- I'm not going to add a ton so the buildings design temp formula is happy when it's 105 degrees outside -- a temp almost never seen in 30 years in my area .... even 100.
ipdaley
Active member
OP
BleedingBlue
Well-known member
Great insight so far! Thanks all for the replies.
I have a company coming tomorrow, who deals Trane almost exclusively, so we will see what they say. My furnace seems to be running great, so shouldn’t need to replace it. But I’m leaning trans so all the pieces match.
I also don’t think I will be paying more for a high seer unit. In Indiana we only need it for 4-6 months a year, so I don’t think it will be worth the investment.
It’s possible I get lucky and don’t need to replace it - fingers crossed.
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I have a company coming tomorrow, who deals Trane almost exclusively, so we will see what they say. My furnace seems to be running great, so shouldn’t need to replace it. But I’m leaning trans so all the pieces match.
I also don’t think I will be paying more for a high seer unit. In Indiana we only need it for 4-6 months a year, so I don’t think it will be worth the investment.
It’s possible I get lucky and don’t need to replace it - fingers crossed.
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Trane/American Standard ain't bad, though their quality control over the past decade or so has faltered some. Though I wouldn't put a new Carrier or Rheem product on my dog house.
Lennox has gone total electronic control and their elite line is quite pricey - I'll wait and see how those things fair for 5 years of use before biting. York is hit and miss. I've got a Tempstar cond unit on my home, connected to a Lennox subsidiary furnace. Works fine.
If I were installing units for people these days - which I'm not - I 'd recommend the basic unit with the least amount of high tech gizmos. 14 SEER is the lowest that can be manufactured, 14 SEER it is. And I'd do a matched system whatever brand the customer opted for, though (in a split system) I might leave the old furnace if it's in really good shape and is less than 12 years old. No sense soaking them for a new furnace if you don't have to. Sure it's easier to just change out everything but I like to help my customers where I can.
Lennox has gone total electronic control and their elite line is quite pricey - I'll wait and see how those things fair for 5 years of use before biting. York is hit and miss. I've got a Tempstar cond unit on my home, connected to a Lennox subsidiary furnace. Works fine.
If I were installing units for people these days - which I'm not - I 'd recommend the basic unit with the least amount of high tech gizmos. 14 SEER is the lowest that can be manufactured, 14 SEER it is. And I'd do a matched system whatever brand the customer opted for, though (in a split system) I might leave the old furnace if it's in really good shape and is less than 12 years old. No sense soaking them for a new furnace if you don't have to. Sure it's easier to just change out everything but I like to help my customers where I can.
Unless it was a high end Trane when installed -- you will not get all the benefits from better equipment unless you replace the furnace. Does your state have any energy programs .. some have incredible programs that include audits and blower door tests (free). Spending for premium equipment to put on top of an old unit may not work out ... what happens in 5 years when the furnace goes? Maybe worth trying to fix the old AC to get 5 more years out of it
The better equipment is as much about comfort -- with a VS fan blower in the furnace and proper controls the newer systems are able to dehumidify and not overcool.
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86turbodsl
Well-known member
Same experience here. 3ton heat pump, 3000 sqft (not counting basement) closed cell spray foam envelope.
OP
BleedingBlue
Well-known member
Do the benefits of getting all new now trump the savings of getting 5 additional years out of the furnace? Also, when the furnace goes out, can I just replace it individually? Not being snarky, I’m genuinely asking.
Replacing a furnace that is working well is a tough pill to swallow. However, I acknowledge that bc it is working now doesn’t it mean it won’t **** out next winter.
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Savings ? How much are you spending now? vs what are you going to save with new equipment. Not much with basic stuff .... add back the cost of the equipment
It really depends on the current equipment in the house ... unless it was advanced at the time it most likely has fixed speed fans and single output AC and Heat .. is it NG.?
Operation: The thermostat calls for heat or cool -- the equipment runs until the thermostat is happy. Today -- everything talks. Heaters modulate with variable speed (VS) fans .. AC/HP's can be two speed up to full VS. They know what temp it is outside .. smart stuff.
You can't put an advanced communicating AC on an old heater -- heater does not have the communication or the VS fan. It would limit you when the heater dies in the future ... because now you need to match the old single speed AC that 5 years old. Also, the performance/ saving from single speed that you have now to a new single speed will not be that great.
I fixed my AC until I junked the whole system ... make sure to look at what energy programs are available.
It really depends on the current equipment in the house ... unless it was advanced at the time it most likely has fixed speed fans and single output AC and Heat .. is it NG.?
Operation: The thermostat calls for heat or cool -- the equipment runs until the thermostat is happy. Today -- everything talks. Heaters modulate with variable speed (VS) fans .. AC/HP's can be two speed up to full VS. They know what temp it is outside .. smart stuff.
You can't put an advanced communicating AC on an old heater -- heater does not have the communication or the VS fan. It would limit you when the heater dies in the future ... because now you need to match the old single speed AC that 5 years old. Also, the performance/ saving from single speed that you have now to a new single speed will not be that great.
I fixed my AC until I junked the whole system ... make sure to look at what energy programs are available.
nsula_country
Well-known member
Everything I install is Rheem/Rudd. Because it's what brand our local supply house carries. Also, so far... They have stood by every component that I have needed warranty on (all parts 10 yr after registration).
Almost ANY unit, from ANY manufacture in the US will have a Copeland Scroll compressor. Be wary of the LG compressors...
CT
Almost ANY unit, from ANY manufacture in the US will have a Copeland Scroll compressor. Be wary of the LG compressors...
CT
Rockhead261
Well-known member
I was an HVAC tech for more than 20-years, but have been pretty much out of the game just as long. I have installed hundreds if not over a thousand systems, given lots of advice over the years, and I think I've helped most of the time.
With that said, this was probably the most helpful and insightful post in this thread. Bravo, sir.
OP
BleedingBlue
Well-known member
AC guy just left and said I have zero refrigerant in my system. My options are to do a leak test/repair/fill and that will be at least $800-$1,000 depending on where the leak is. I have the "old" refrigerant.
He is recommending a new unit. Ugh
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He is recommending a new unit. Ugh
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Trey T
Well-known member
^find one that's familiar and willing to learn about alternative R-22. I highly recommend MO-99 for R-22 alternative.
When did it last work? Had you ever had it filled. So, he did not do a pressure test? .. think they use nitrogen?
You could have a large leak -- but, that would be easy to find if looked for.
Not to knock the HVAC industry --- but, finding and fixing a leak provides no payback. It labor that could be making more. Filling a system every year and replacing them .. that's the payback.
It could be something as simple as the fill valve --- they are schrader valves. I learned years ago when you have a slow leak replace the valves -- or nothing in the system .... check for leaks and replace the valves.
I bought an old house years ago and the AC needed a hit of freon every year -- the service company naturally did it and sent me a bill. The house had oil heat and I would get a service contract for the heaters .......The first year I decided to included the AC in my service contract the guy who came out to service it replaced both schrader valves. There is a special little tool that switches them out in about 30 seconds. He tells me ''these things leak all the time -- we replace the valves if the unit is down a pound or so" .... never touched again.
eddieK
Well-known member
Two things -
First, 13 yrs? A Trane should have lasted longer.
Second - Best brands in my almost 40 yrs experience...note necessarily in order.
Lennox - Trane - Rheem (including their builders models under different names)
Second tier- Carrier - York
More importantly I highly recommend copper tube and aluminum fin coil construction, many manufacturers only make aluminum micro channel coils today. Great warranty until you realize 7 yes down the road that your all parts warranty for a replacement condensing coil still leaves you a $1,500.00 minimum billing.
eddieK
Well-known member
Those coils are icing for some reason...improper indoor outdoor sizing- clogged filters - inadequate return air...low temps called for without head pressure control
OP
BleedingBlue
Well-known member
I have never had it filled in the three years I have lived here. It worked last summer.
I’m not familiar with what he did exactly, but he measured the refrigerant and said the number was very low....18 if I recall.
He said the next test to find the leak would be using nitrogen, but it would cost $500 for labor and probably another $3-400 for the refrigerant. He said he guessed the leak was inside the house inside what I thought was the heater.
Should I have another company come out?
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They typically put gauges on it to see how low ... it may have been too low fill. I'm not sure if it's country wide .. but you just can't fill a leaking R22 system when it's down too much. The theory is it's just going to leak out agin. Years ago they just filled them up and looked for the leak.
If it really was empty - he could have done the nitrogen. They use a tester to detect the presence of the freon.
I'm trying to understand why he did not look for the leak and assumed it was inside. Unless he detected something?
Obviously, if you find a big leak .. you know what needs to be done.
If it really was empty - he could have done the nitrogen. They use a tester to detect the presence of the freon.
I'm trying to understand why he did not look for the leak and assumed it was inside. Unless he detected something?
Obviously, if you find a big leak .. you know what needs to be done.
OP
BleedingBlue
Well-known member
He said he hooked up a gauge and it had essentially no refrigerant in the line. He said to do the nitrogen leak test it would cost $500 (plus coat for new refrigerant - think it was around $140/lb), so i told him not to go down that path until I could think it over.
He wouldnt just add refrigerant without doing a leak test (i asked).
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LS6 Tommy
Well-known member
That's because he's probably a decent technician. I wouldn't do it either for a leak that big.
Tommy
danski0224
Well-known member
If there is refrigerant in the system, and if the system is above atmospheric pressure (0 psig), there is enough in the system to check for leaks.
Leaving the system "off" (no fan/blower) for a couple of hours and then sticking a refrigerant leak detector probe into the condensate drain is a pretty easy go/no go test. Service charge and 30 minutes of labor at most.
If the system is indeed near 0 psig, put 150 psig of nitrogen in the system and then sniff it and listen for leaks- there is still MORE than enough residual refrigerant in the system to set off a sniffer. If there isn't anything found, evacuate it and charge it up.
The Schrader valves have been mentioned. Those chintzy black plastic service port caps leak too. So do the king valve caps if they aren't tightened like they are supposed to be.
Obvious oil stains on the condenser fins or anywhere outside?
Hidden lineset joins and leaks are hard to find.
If the evaporator coil passes the sniff test, and if there aren't any obvious leak tell-tales otherwise, I'd fill it and charge it properly, put brass caps on the access ports, tighten the king valve caps, put UV dye in it, then check it again next year.
A digital manifold and superheat/subcooling measurements are virtually a necessity to get enough accuracy to set the initial charge and to check it next time.
I have several "condemned" systems that continue to work just fine. Shady HVAC companies leave intentional leaks, like those loose caps.
Systems that "worked" last season and then don't work the next one, with a heating season inbetween typically have a failed evaporator coil. However, unless the system is serviced regularly and you have a known good starting point, a slow leak (loose caps) over several years can render a system inoperative.
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But, why should it cost $500 to check ?
danski0224
Well-known member
And how do you know how big the leak is from the information provided?
eddieK
Well-known member
Let me explain what I do when I encounter this.
If I have never serviced this split system before, I start by verifying things at the furnace and indoor coil.
Does the system match in capacity and SEER? Is the indoor blower wheel clean or are the cups in the wheel packed with dirt? Is the evaporator coil clean or is it blocked by debris? Is the indoor return the proper size and is the air flow through the supply system restricted. All of these things can affect the charge in the system and provide false charge data, yet they also provide answers to errors in the system.
Once you start the system up with gauges on the ports and a temp gauge on the liquid line outside you let it operate for 10 minutes. (if there is not much refrigerant noticed immediately, you do not let it run).
If after these basic measures it appears to not be fully charged I tell the customer they have some choices, this could have been a situation where it was originally charged incorrectly or it could have a leak.
Before we do a leak seal and search procedure, this season we should finalize the charge by the super heat method looking for 12 degrees of superheat. We can insert a leak sealant hoping to seal a minor leak (ounces per monthS) or we could just charge it up and test again later.
If it is a return visit and it has lost more, I suggest the leak search and seal procedure.
These usually cost at least $700.00 - $1,200.00 depending on how many pounds and what type refrigerant required.
The complete project takes at least 4 hours, sometimes longer. first you reclaim the remaining refrigerant in a tank, then you insert nitrogen and I like to test at 100 pounds first - then at 350. More time consuming items, because you must let the system equalize by allowing at least 40 - 45 minutes before you determine it is NOT leaking. There are common leak points, all connecting fittings, txv's or check flo rater pistons, coil ends, capillary lines rubbing against others or sheet metal, these last two can be time consuming to access to check with soapy bubbles (I am not a fan of dye insertion, because I can not be sure what damage, clogging it may eventually cause, usually a long time after insertion). All of this is even more difficult (time consuming)to accomplish if the indoor portion is a horizontal in an attic space. Once the leak is located you open the system, nitrogen purge at very low rate and braze the repair. It can take sometimes quite a while to remove rubatex, trace piping, access components etc...or the leak could reveal itself really fast.
Next, you install a liquid line filter drier because the system has been opened up, insert new shrader valve inserts (after vacuum procedure because you remove them to do the vacuum), you put the system on a vacuum until it reaches at least 500 microns and does not rise above 1000 when sealed from the pump. These vacuum procedure should always at least be one hour long and in some cases it can take up to 4 hours to achieve proper vacuum.
Then you weigh in proper delivery charge and start up, wait ten minutes and finalize charge by the super heat method.
Hope this helps
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eddieK
Well-known member
How fast it leaks down under nitrogen pressure...Huge leaks are rare and simple to diagnose/repair, small leaks are very common and can be very difficult to isolate.
danski0224
Well-known member
Right, but no tests have been done yet 
get all that ..but, thanks for the detailed time line.
It sounds like the OP's tech just looked at the charge and pronounced it dead. I would expect a good tech to do some looking. Seeing oil on the condenser or finding it in the evaporator drain would not be a good sign --
...maybe I'm wrong .. but I think better to spend 1k fixing the old system in good shape to keep it running for a few years .. vs spending 3k for a new AC to put on top of an old heater.
My history is that they all end up being fixable -- I do hate those schrader valves and insist on new ones if they are touched.
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eddieK
Well-known member
Right, but no tests have been done yet
No way to tell - minor test is just putting gages on the system at start up. After initial start test you can usually make a guess as to percentage lost...but there are multiple factors involved, such as heat load, ambient temps, air movement etc.
Refrigeration and A/C diagnosis invloves complete dynamics.
eddieK
Well-known member
Even new shraders can stick after removing gages...Most techs I know replace em...they are super cheap. But...sometimes they are in a position, depending on manufacturer, where shrader removal tool will not work.
Falcon67
Well-known member
Same - why we have a Ruud. Locals keep parts. Our service guy prefers the brand for that reason - if parts are needed, he can get them. Carrier, etc - have to order. Part cost+shipping+install if not a warranty thing. Takes a couple of days to get things here if not stocked locally.
LS6 Tommy
Well-known member
Aren't you in the industry? $500.00 may seem a little high, but a decent shop will charge ~$90.00/hour. Performing a good leak test takes tim. You have to disassemble or open up the indoor and outdoor units in order to get at all the possible leak areas, remove the insulation at areas where you suspect there is a joint and put it all back together again.There's also cost of materials and equipment use.
30+ years of experience...
Seriously, Bleeding Blue says it was at 18# static. That tells me it's a good sized leak since he also says it's run for the last 3 years without needing to add refrigerant (assuming someone actually checked operating pressures each year). A minor leak will usually only need a little squirt every year or so.Tommy
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