Is this an HVAC repair scam?

6 years ago

My gas furnace was inspected and showed high CO levels in the exhaust plenum. This is a 22 years old high efficiency (90%) unit that has PVC piping for supply air and exhaust gas. The CO reading in the return air duct was 0 ppm and in the exhaust plenum was around 500 ppm. The efficiency reading was 88%. The burner flame appeared to be steady even when the blower started. Based on the high CO levels, the tech concluded that the heat exchanger is cracked and needs to be replace for a labor fee of $2,300 (the heat exchanger has lifetime warranty).
Given that the ambient air CO level is zero and the burner flame appeared to be steady with the blower on, the high CO levels in exhaust plenum should not be a problem.
So is this the cracked heat exchanger scam?

Featured Answer

PRO

Austin Air Companie

6 years ago

Did you pay for the CO test and how much? (This is typically a leading indicator)

Also furnaces do not make CO (carbon monoxide) they make CO2 (carbon dioxide)

When they do make CO (carbon monoxide) it is typically due to improper combustion. This can be due to a lack of combustion air.

These problems are sometimes created after the fact by changes to the room or area the furnace sits or sometimes a product of inferior system design.

With that said, has anyone in the home been sick recently and the furnace was running?

Carbon Monoxide is a colorless odorless gas. It can kill you. Problem is scam artists know this.

Even if you don't have carbon monoxide, if the heat exchanger has cracks this is not a safe condition for operation.

Sort by:Oldest

Comments (7)

Elmer J Fudd
6 years ago
last modified: 6 years ago
If you live somewhere with cold winters (such that the furnace gets a lot of use), a 22 year old furnace could easily be at end of life. Heck, any 22 year old furnace has reached old age, no matter where.

If you don't trust what you were told, pay for a service call from another provider. Paying $2300 for a new heat exchanger for a 22 year old furnace is like paying $10,000 for a new engine for a 22 year old Toyota - I wouldn't do it unless you can't afford a new one.
tigerdunes
6 years ago
Scam?...could be...deserves another look by a reputable HVAC dealer..
Related Discussions
HVAC Repair or replace????
Q
Comments (11)
Most often I repair these kinds of units when home owner tells me the plan of 3 to 5 years or less of living at a particular residence. Sure there are risks in further breakage, but a new system is not without risk either. A new entry level system break even is around 10 year mark, you won't make anything off of it on a home sale... it will merely help you sell the home to one degree or another. If you live there 5 more years then sell, once ownership of the home changes the warranty on the system you buy reverts to the 5 year standard warranty. It's always better for the new home owner to install a system to their liking. Under this sort of premise it's a toss up as to whether to repair vs. replace. If the leak is in fact in the outdoor unit this will complicate repairs because replacement condenser coils are very expensive and in the realm of American Standard or Trane they are aluminum spiny fin coil. It's typically not worth trying to repair them / can be difficult in many cases. You can't buy a new R22 condenser, so it means a refrigerant conversion would have to be performed. That requires skill. Much of which is lacking in the HVAC field for some time. This is a complicated repair. It can be done, provided the right skill set required is found. I service the Katy, Texas area.
...See More
Is my HVAC high limit switch working or not? Two HVAC pros said it is.
Q
Comments (25)
WHAT IS A HIGH LIMIT SWITCH? https://www.newcentralairconditioner.com/ The high limit switch in your gas furnace is a small part with two very important jobs. This switch plays a role in the normal operation of your furnace. Turning the fan motor on and off is the high limit switch’s main job. This is the role it plays in every cycle of your furnace’s normal operation. But that’s not the only thing that the high limit switch does. It’s also safety device that helps prevent your furnace from overheating. The high limit switch consists of a long temperature-sensing probe attached to a metal mounting plate. From the mounting plate, the switch is wired to the blower fan motor and to the gas valve. The switch is generally located just past the heat exchanger. This is so that it can detect the temperature of the supply air. In other words, the air that’s about to be blown into your home.
...See More
Single HVAC zoned or two HVACs without zoned system
Q
Comments (27)
The biggest problem with HVAC zone systems is knowing when to choose it as a solution and when not to. Some HVAC companies it's about "sell, sell, sell" whether or not it works... there's more money in "sell, sell, sell" --- when it's only about money? So does the comment above mean I do it for free? No. If you think that you are reading things that aren't there. New construction? best to choose separate systems 9 times out of 10. In order for a zone system to work, you have to know what you are doing. Most HVAC companies staff (the techs they send you) are 20-30 year olds. How much practical experience could they possible have? It's best for HVAC zone systems to be an elegant solution. A HVAC zone system is a tool in the tool bag. Not all homes are suitable for zone systems. Some homes there is no other way, and in some cases complications to those problems will make an HVAC zone system design possibly more prone to problems. You have a problem now, do you want more problems. These decisions among others are decided "in person" --- so considering that becareful what information you decide upon from the internet. Just because it's here doesn't necessarily mean it's true. That said: Depending on equipment level chosen, how many different floors you have in your structure, how much room you have available... will all be factors that make you decide one way or another. From there it's in your best interest to pick a contractor that is skilled: especially when it comes to HVAC zone systems. (there's a lot of garbage out there.) (click to enlarge if necessary) I service the Katy, Texas area.
...See More
NVR Dan Ryan Homes HVAC Sizing SCAM
Q
Comments (9)
We understand that NVR Dan Ryan Homes, probably not the best builder. These posts serve very little purpose. As far as sizing: Our 3600 sq ft house in Indiana served fine by 3.5T AC with 4T coil 110K BTU furnace, my neighbour chose to upgrade his house 3200 sq ft to 3.5T and the system is not working properly. Cools down pretty fast without removing moisture. My planned 4,000 sq ft engineered ( by us ) has total demand load 2.5T (2800BTUH), but because of Manual S and the heating load 68k matching equipment from AHRI directory may have to go 3.5 or even 4T. furnace will need to deliver 72k heat, but to deliver this BTUH it has to have higher CFM rating on the blower. while you can have a different CFMs on cooling and heating... The ductwork design does not work well when cooling CFMs are 980s and heating CFMs 1490s. So Manual S calls for higher rated AC or ASH unit. Without knowing locations and the load, I think calling NVR Dan Ryan Homes HVAC Sizing SCAM is a little harsh. The ZoneX system does not compensate for load, it probably balances upper and lower floors temperature. Without it there would a significant temperature difference between floors. NVRs issue in my opinion is not with sizing, rather not so good exterior details that leak air.
...See More
dirtmechanic
6 years ago
Probably not on a 22 year old heat exhanger made of thin metal operating in a highly corrosive oxidation environment. Since CO will kill you, and is the main risk, you had better get this right and invite others to measure it. Further, it does not seem correct "has PVC piping for supply air and exhaust gas." that you have PVC exhaust as the plastic is not suitable for heat, so your grasp of the situation needs to be clarified since mistakes with gas heat can have mortal consequences.
mike_home
6 years ago
Based on the initial posting, I am going to call this one a scam. But carbon monoxide is very serious, so you need some follow up.

If the PVC has exhaust has a high level of CO, then it should not be a danger unless the exhaust was installed too close to a window that can be opened. That is why installation rules exist. A think a level of 500 ppm is high. Look at the flame. If it looks yellowish and not blue then you may have a combustion problem that needs to be fixed.

Did the tester measure the CO coming out of the supply? That is the measurement that is important. Did the tester do a visual inspection of the heat exchanger to verify it is cracked? Does the flame dance around or looked distorted. These are indications of a potential cracked heat exchanger. It is not fool proof, but something the tester should have at least inspected.

Just because a furnace is 22 year old does not mean the heat exchanger is probably cracked. You are don't the right thing to have it checked, but get a second opinion before you spend thousands of dollars.
sktn77a
6 years ago
What do you mean by "exhaust plenum"? Do you mean the supply plenum? If so, I'd have the reading double checked.
majm99
6 years ago
Yes, it's probably a scam. But you may have an issue with the gas valve, burners, or the exhaust being restricted. When you have a cracked heat exchanger, it's potentially very dangerous if you also have high CO in your system's exhaust because a crack could let exhaust gas into your home.

Replacing a heat exchanger has no effect on the CO levels in the exhaust plenum of your furnace, it only isolates the exhaust from the inside of your home - in your case, that's already happening (from what you wrote, it sounds like the high CO is only in the exhaust which means the heat exchanger is OK).

High efficiency furnaces and boilers save energy by condensing hot exhaust instead of sending that energy out a chimney. The liquid that is a result of this energy saving process is very acidic and, while careful selection of materials slows the process, that acid inevitably shortens the life of the furnace.

At 22 years, you're going to need a new furnace soon, but you may want to explore getting it from someone else. It's possible that you misunderstood what he was telling you. If not, then you need a different tech because this one doesn't know enough about furnaces and how they work.

Is this an HVAC repair scam?

Austin Air Companie

Comments (7)

Elmer J Fudd

tigerdunes

Related Discussions

dirtmechanic

mike_home

sktn77a

majm99

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US