I would believe your heat exchanger should be covered under warranty. You may have to pay for labor but that's much cheaper than buying a new furnace and labor. I had a crack develop on the heat exchanger on my then 13 year old Lennox furnace, no CO leaks. I paid labor only. Check Carrier's policy. I did not have to provide maintenance records. My cost was about 25% of the cost of a new furnace. It's 21 years old now and still working good.
Carrier Infinity Furnace Heat exchanger shot
- Thread starter Cropduster172
- Start date
Best most squared away advice I've read in years
My 22 year old 100,000 BTU Carrier Infinity 58MVP100 just had the secondary heat exchanger go bad. Water on basement floor, stinky exhaust, etc.
20 year secondary heat exchanger warranty - bummer. I think this model had an extended warranty (not just for the original owner) due to ongoing issues.
But…. Turns out the secondary heat exchanger was replaced just 4 years ago, before I bought the house. Got another new one under warranty. Then the CO levels were still too high, so they replaced the primary heat exchangers, also under warranty. They also upgraded the PVC intake & exhaust pipes from 2” to 3”.
More than happy with my local certified Carrier place and the Carrier warranty.
20 year secondary heat exchanger warranty - bummer. I think this model had an extended warranty (not just for the original owner) due to ongoing issues.
But…. Turns out the secondary heat exchanger was replaced just 4 years ago, before I bought the house. Got another new one under warranty. Then the CO levels were still too high, so they replaced the primary heat exchangers, also under warranty. They also upgraded the PVC intake & exhaust pipes from 2” to 3”.
More than happy with my local certified Carrier place and the Carrier warranty.
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2 failing in 12 years is a common failure?
Good old carrier 58 series heat exchangers are known for this. I had 3 with bad heat exchangers last week. Two of them were under warranty and when I called about it they advised me that a couple of the parts of the heat exchanger were on back order with no estimated time of arrival.
The problem with the 58 series heat exchanger is the secondary heat exchager has a coating inside and when it starts to break down it plugs the heat exchanger. The heat exchanger will also start to rust out from the inside out and start leaking water. When they start to get plugged they will trip the roll out switches by the burner and throw pressure switch codes. They also will start turning the inside of the pvc exhaust pipe black. They make a smell that I dont know how to describe but once you have smelled it you will never forget it.
The problem with the 58 series heat exchanger is the secondary heat exchager has a coating inside and when it starts to break down it plugs the heat exchanger. The heat exchanger will also start to rust out from the inside out and start leaking water. When they start to get plugged they will trip the roll out switches by the burner and throw pressure switch codes. They also will start turning the inside of the pvc exhaust pipe black. They make a smell that I dont know how to describe but once you have smelled it you will never forget it.
So it seems the cost of the heat exchanger itself is a warranty item but that labor to install is not. Got to figure it's a 4-6 hour job. Than I wonder if the replacement is fabricated the same way or made from stainless steel.
Got prices for new furnaces...$4700-$7300.
If I replace the furnace I want a single stage 95 AFUE Payne.
I don't know if carrier ever fixed the issue with 58 series heat exchanger or not.
Why do you want a Payne? Payne is Carriers cheapest line. Don't get me wrong they work but that wouldn't be my first choice.
Is it Payne or Bryant. I already have the Carrier AC which works fine. Iight also go with the mid level Carrier. I do not want a two stage furnace. Don't need it and don't believe the sales hype that's used to market them. 2 stage saves me nothing in efficiency, I'm in SE PA, not Yellowknife. More complicated, more expensive, more expensive for parts. Single stage. Keep it simple.
Carrier and Payne are the same. Had a Carrier furnace in our old home that was still running strong after 39 years.
Whats the model number on your current furnace?
58MVC100
Ironic, just had my heat exchange fail on my Bryant, though it's an older 398 series, pre-dates error codes and LEDs. Pilot was taking forever to light, then once it got the burners going, flame roll out and most recently they won't stay lit, so now using space heaters and checking them frequently to make sure the cords and outlets aren't getting hot.
I'll probably replace it with a Tempstar (another Carrier brand), because my cousin owns an HVAC business and can Hook Me Up, and get it put in soon so I don't have to rely on space heaters, as the furnace was running with the cover off but started smelling gas, so no, had to shut it down.
Maybe, but not much for furnace instead of A/C use. The extra wattage is converted into heat, so while you are paying (varies by region) around a 45% premium for the heat to be electric instead of gas, that's only around 2000 BTUs worth, 2% of the total in the case of a 100K BTU furnace, so all else equal the furnace is using 2% less gas to achieve the target temperature.
I mean this in context, that the ~600W motor had to be PSC type, which are no longer used (2019 mandate got rid of them), so today you're more looking at whether the ECM motor is on a single or dual stage furnace, the latter saving maybe 100W but this is only 0.33% difference. On the other hand the 2nd stage, does save single-digit more in efficiency, but as explained previously in this topic, that 2nd stage can bring with it, an additional failure mode in addition to higher furnace cost.
I'll probably replace it with a Tempstar (another Carrier brand), because my cousin owns an HVAC business and can Hook Me Up, and get it put in soon so I don't have to rely on space heaters, as the furnace was running with the cover off but started smelling gas, so no, had to shut it down.
Maybe, but not much for furnace instead of A/C use. The extra wattage is converted into heat, so while you are paying (varies by region) around a 45% premium for the heat to be electric instead of gas, that's only around 2000 BTUs worth, 2% of the total in the case of a 100K BTU furnace, so all else equal the furnace is using 2% less gas to achieve the target temperature.
I mean this in context, that the ~600W motor had to be PSC type, which are no longer used (2019 mandate got rid of them), so today you're more looking at whether the ECM motor is on a single or dual stage furnace, the latter saving maybe 100W but this is only 0.33% difference. On the other hand the 2nd stage, does save single-digit more in efficiency, but as explained previously in this topic, that 2nd stage can bring with it, an additional failure mode in addition to higher furnace cost.
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It's at the stage now where it's tripping the roll out switches but it's not running much as all. Mid 40s here and I can heat the main floor and the master with fireplaces. HVAC contractor is putting together warranty options from Carrier...we'll see what value there is, if any, with those options. I'm sure it will be several hundred dollars off of an overpriced system that I don't need.
I am talking about the fan blower motor which runs continuously on my furnace in the winter. I am not gaining any amount of useable heat from the extra 500 wats of electricity wasted in the old motor? I noticed the electric savings and much as the gas savings on my bills. The gas valve on my Lennox can vary from 40-100% and the blower fan can go even lower than 40% I believe.
^ Something "could" be wrong (might just be the thermostat, fan setting) if the blower runs, more than a few seconds to minute(s) after the burners shut off to extract remaining heat out.
However, if your motor is using 500W, that 500W becomes ~1700 BTU heat, it is the final entropy of the power, result is like if it were a 500W electric space heater. Even so it is not enough to bother with, constantly running the motor will wear it out faster and increase dust clogging and filter replacement.
If it is designed to counter this with variable speed, and gas, in a newer furnace, then of course the immediate consumption goes down but it also has to run longer which offsets that, with the alternative being single speed but still ECM, more efficient motor in a modern post-2019 furnace (or higher end, before the 2019 mandate). Just-right-sizing is more efficient for A/C than for heating where it's more a matter of adding another stage to extract more heat.
However, if your motor is using 500W, that 500W becomes ~1700 BTU heat, it is the final entropy of the power, result is like if it were a 500W electric space heater. Even so it is not enough to bother with, constantly running the motor will wear it out faster and increase dust clogging and filter replacement.
If it is designed to counter this with variable speed, and gas, in a newer furnace, then of course the immediate consumption goes down but it also has to run longer which offsets that, with the alternative being single speed but still ECM, more efficient motor in a modern post-2019 furnace (or higher end, before the 2019 mandate). Just-right-sizing is more efficient for A/C than for heating where it's more a matter of adding another stage to extract more heat.
Decision made. Payne single stage 100,000BTU furnace with ECM motor.
Keep the existing humidifier. New air filter box.
$525 credit from Carrier. Be approximately $4300.
I'm OK with that.
Keep the existing humidifier. New air filter box.
$525 credit from Carrier. Be approximately $4300.
I'm OK with that.
You are over thinking this. Nothing is wrong with the system. They are designed to run this way. System figures out how hard it needs to run based on inside/outside temp and how far the desired temp is from the actual temp. When done heating the fan goes down to the lowest setting to keep air circulating. Read up on it. It provides a much more comfortable heat and constant temp in the house. A single stage is either on or off and you get temperature swings and is less efficient. If you are in MN you want a better furnace than AC since it gets used a lot more during the year. If I was in a milder climate I would get a single stage.
Your example is using a 500W that is using all of its energy to heat when most of it is being used to turn the motor, unless you have a really inefficient motor? Otherwise I could run a 500W fan and heat a room? Makes no sense.
Two stage furnaces are way overrated. They are significantly more prone to breakdown. Parts are more expensive and they are more comple complicated.
I'm in a center unit two story townhouse...with two exposed walls and a roof. A properly sized single stage Payne with an ECM motor is quite adequate. Additionally, there is a see through, vent free fireplace in the dead center of the first floor. It easily heats the entire main floor..very quickly.
I'm just waiting to set an install date ASAP
In your case sure, but I'm not sure what that had to so with my comment? I was explaining how it worked. I think it depends on what part of the country you live in. Mine is essentially infinite stage heating from 40 to 100% and I haven't had any issues in 13 years.
You don't seem to understand the tech. The old PSC motors that use 500W, are only single speed motors, or sometimes two speed, are not the type that should always be running, unless the thermostat is set to always run the fan, so not an apples:apples comparison of power.
A variable speed ECM motor like yours is (and every other furnace since 2019 and earlier for higher end models), does not need to run constantly to recirculate the air. It can, but for this negligible difference, it wastes power and increases wear, and filter replacement events.
Running constantly will keep all areas of the room more equal in temperature, for example reducing cold spots near windows, doors and other loss areas, but overall it uses more power to achieve this, more power for same average temperature. It is actually more power for a slightly lower average temperature because circulating the warmer air to the colder area, increases heat loss, but it is not really enough to consider since you wouldn't want an extreme enough temperature difference for this latter factor to be as significant as the others.
Any motor, at any speed, ALL of the energy is converted to heat. Makes no difference how efficient it is. Turning the motor does not change that the power is turned into heat. Yes, a motor that consumes 500W, would heat a room exactly the same amount as a 500W space heater. Similarly, a 200W (measured at steady load) computer, heats the room the same as a 200W space heater, an 11W LED bulb, same as 11W space heater, and so on.
It does not matter if the motor is doing "work", suppose a treadmill motor using 500W to move the belt, is still producing same heat as a 500W space heater. All watts become heat eventually. One pseudo-exception is charging things. If your cellphone charger uses 10W to charge your phone, the energy stored in the battery will have to be discharged, before you achieve 10W heat output.
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Yeah. Enough. Sorry I asked
