Carrier Infinity Furnace Heat exchanger shot

[Cropduster172]

That is where you can buy the Ecoboee wireless sensors to combat this if it becomes a problem. You can place the sensors anywhere within wireless range of the main Ecobee and it can use those temps (or average between thermostat and sensors) to adjust the heating and cooling. It works well for me.

I've thought of that. I did buy an indoor/outdoor wireless thermometer that measures temperature and humidity. Since we really only use the fireplace from about 4-6PM....sometimes later watching TV and we like the room somewhat colder when we sleep(63-66), it's not a problem. The indoor receiver portion of the thermometer tells me the ecobee is spot on with its temperature and humidity measurements.
I'll take another look at those sensors when AC season rolls around.

 

[alarmguy]

This is good advice. They're are relatively inexpensive. I bought 3 at Home Depot for about $17 each.
Put one in the furnace room and one on each floor. We have a vent free gas fireplace too. Which is fantastic at heating the entire first floor of the house. But it's only about 15' from the thermostat so it effects the heat flow to the second floor. Not a big deal though.

Yeah, I am convinced a CO dectector saved my wife, 2 kids and myself life a couple decades back when we lived on Long Island.
I had one in an area of our oil furnace, we just went to bed and about an hour later we were woken by a strange beeping that I didnt know what it was except I knew it wasnt a smoke alarm. Half asleep I got up and started walking and looking around to see where the strange "beep" was coming from. Finally narrowed it to the laundry/workshop, furnace area and there it was, the CO detector that was there forever was sounding.

TEXT BOOK situation = I didnt smell a thing, furnace was like new at only a year or two old.
Shut down the furnace right away, called our oil company, came over, there was about 3 feet of birds nest (with dead birds too) in our stainless steel chimney clogging it up.
Something I will never forget when it comes to having safety devices in a home. To this day now, I also stock good size fire extinguishers in a specific place of each closet on the second floor of the house, with a roll out emergency ladder should a windows escape be needed as our house is much larger here. As well as a few extinguishers on the main level. Stuff is dirt cheap insurance that lasts a very long time.

 

[hemitom]

My parents original Lennox went 21 years before needing major work. I'd go that route. A cracked heat exchanger is not good. That can allow CO to leak inside the house.

Not can ! it will allow CO to be pushed through the duct work

 

[brianl703]

I noticed that immediately. They told me the DC drew about 60W and my old AC squirrel cage motor was about 500-600 Watts. So quiet too, all you hear is air.

ECM motors save energy over PSC motors when they are run at slower speeds Otherwise, an ECM motor won't save much, if any, energy over a PSC motor which is running at it's top speed.

I have an ECM motor in my heat pump air handler and it pulls the expected 600 watts when running in heat or cool (about the same as a PSC motor running at the same speed with the same load). When running in fan only, however, it operates at much slower speed and only pulls around 60 watts, something a PSC motor cannot do.

Also something a PSC motor cannot do is providing a multitude of speed options. This air handler has fan speed settings for tonnage from 2 to 5 tons with high/low/medium speed options for each. Your typical PSC motor gives you 3 or 4 speeds, and that's it. And, as mentioned, at anything other than the high speed setting, the PSC motor loses efficiency.

 

[brianl703]

Not can ! it will allow CO to be pushed through the duct work

The biggest issue with a cracked heat exchanger is that it can allow flame rollout. Modern furnaces have a flame rollout sensor to detect this.

This happens because the air on the outside of the heat exchanger is at a higher pressure than the inside of the heat exchanger, and it will actually push the flames out of the heat exchanger back towards the inshot burners.

This also means that it's not usual that a heat exchanger leak or crack will allow CO to get into the duct work.

 

[hemitom]

well according to my fire fighter friend happens often , we actually had this conversation early this week playing hockey . They got called out to a duplex tenant tells them co alarm is going off scan apartment rooms showing up to 2000ppm nearly same readings as owner occupied unit below.
to sum up ten year old lennox gas furnace cracked heat exchanger.

 

[brianl703]

well according to my fire fighter friend happens often , we actually had this conversation early this week playing hockey . They got called out to a duplex tenant tells them co alarm is going off scan apartment rooms showing up to 2000ppm nearly same readings as owner occupied unit below.
to sum up ten year old lennox gas furnace cracked heat exchanger.

Probably that heat exchanger was cracked before the co alarm started going off. The alarm probably started going off once the crack got big enough. Usually the furnace trips the rollout sensor and shuts down before it gets to that point. Possible someone bypassed it.

 

[tmorris1]

ECM motors save energy over PSC motors when they are run at slower speeds Otherwise, an ECM motor won't save much, if any, energy over a PSC motor which is running at it's top speed.

I have an ECM motor in my heat pump air handler and it pulls the expected 600 watts when running in heat or cool (about the same as a PSC motor running at the same speed with the same load). When running in fan only, however, it operates at much slower speed and only pulls around 60 watts, something a PSC motor cannot do.

Also something a PSC motor cannot do is providing a multitude of speed options. This air handler has fan speed settings for tonnage from 2 to 5 tons with high/low/medium speed options for each. Your typical PSC motor gives you 3 or 4 speeds, and that's it. And, as mentioned, at anything other than the high speed setting, the PSC motor loses efficiency.

Whatever the case, it saved me noticeable money on my electric bill. The old furnace fan only ran when heating or cooling, and the new one goes to low speed when not heating. It must also be more efficient than the old one when running at higher speeds too because the new fan runs a lot more than the old one ever did and still saved money. Could be newer bearings etc, too.

 

[brianl703]

Whatever the case, it saved me noticeable money on my electric bill. The old furnace fan only ran when heating or cooling, and the new one goes to low speed when not heating. It must also be more efficient than the old one when running at higher speeds too because the new fan runs a lot more than the old one ever did and still saved money. Could be newer bearings etc, too.

Did you run the old furnace with the fan on all the time?

 

[dbias]

I had the heat exchanger replaced on the Goodman that was installed here when I moved in. It went out at 9 years and was replaced under warranty. The gas in my area is higher pressure and the installer didn't set the pressure correctly so the flame was shooting clear back into the first turn.

 

[tmorris1]

Did you run the old furnace with the fan on all the time?

No

 

[Mikek13]

I realize this is a older thread, but thought I might add my two cents.
I also have a carrier Infinity that I installed 23 years ago. Other than a burnt blower thermister, It's only needed filter replacement, but needless to say it needs to be replaced.
This furnace is listed under those affected by a class action lawsuit for faulty secondary heat exchangers. Check here for the details-
http://hipspro.com/pubs/Furnace-clasaction-detailed_notice.pdf
From what I'm gathering, all furnaces are junk anymore unless someone in the industry can correct me..

 

[Lubener]

I realize this is a older thread, but thought I might add my two cents.
I also have a carrier Infinity that I installed 23 years ago. Other than a burnt blower thermister, It's only needed filter replacement, but needless to say it needs to be replaced.
This furnace is listed under those affected by a class action lawsuit for faulty secondary heat exchangers. Check here for the details-
http://hipspro.com/pubs/Furnace-clasaction-detailed_notice.pdf
From what I'm gathering, all furnaces are junk anymore unless someone in the industry can correct me..

Your two cents is worth one cent thinking every furnace is junk.

 

[Cropduster172]

Your two cents is worth one cent thinking every furnace is junk.

Have to agree. Had a Bryant horizontal furnace in our beach house. HVAC tech. ran the serial number...it was 24 years old. Never serviced it for the 14 years we owned the place...just was religious about changing the generic filters. Furnace was fine but the AC was leaking oil. Replaced everything with another Bryant system. Simpler is better. Went with a single stage Payne last winter when the Carrier Infinity secondary heat exchanger failed in our main house.

 

[CDX825]

I realize this is a older thread, but thought I might add my two cents.
I also have a carrier Infinity that I installed 23 years ago. Other than a burnt blower thermister, It's only needed filter replacement, but needless to say it needs to be replaced.
This furnace is listed under those affected by a class action lawsuit for faulty secondary heat exchangers. Check here for the details-
http://hipspro.com/pubs/Furnace-clasaction-detailed_notice.pdf
From what I'm gathering, all furnaces are junk anymore unless someone in the industry can correct me..

American Standard/ Trane is the only one I feel that is a step above the rest. They have stainless steel primary and secondary heat exchangers. Everyone else is using aluminized steel for the primary and stainless for the secondary.

 

[Donald]

Was getting error codes for limit switch. It's an 11 year old Carrier Infinity. The tech. came out, cleaned the burners and showed me the flame roll out.
It's the heat exchanger...no argument.
Question is do you pay to replace the heat exchanger or get a new furnace?
AC is fine...so it's just the furnace.
AFUE 90.
Carrier does warranty the heat exchanger but is adamant about proving routine service which I can't do as we've only been here a year and no service records left fo the HVAC system.
My inclination is to replace the furnace with a mid level with fewer bells and whistles...a Bryant or Payne....both Carrier brands.

Heat pump and get the gov tax credits.

 

[Cropduster172]

American Standard/ Trane is the only one I feel that is a step above the rest. They have stainless steel primary and secondary heat exchangers. Everyone else is using aluminized steel for the primary and stainless for the secondary.

Yeah...the use of stainless for the heat exchangers is not exclusive to Trane. My Payne has a SS heat exchanger. The manufacturers learned the hard way after class action suits forced them to extended warranties and credits for repair or replacement that cutting corners there with aluminum wasn't the best decision.

 

[hrv]

Your two cents is worth one cent thinking every furnace is junk.

After my Goodman HVAC lasted over 21 years I had a new Carrier installed in 2018. One thing the tech told me was... Dont expect 20 some years from all of the newer ones...maybe 10 to 15 at the most... Also my heat exchanged has a 20 year warranty from the factory...

 

[CDX825]

Yeah...the use of stainless for the heat exchangers is not exclusive to Trane. My Payne has a SS heat exchanger. The manufacturers learned the hard way after class action suits forced them to extended warranties and credits for repair or replacement that cutting corners there with aluminum wasn't the best decision.

Only Payne furnace with a stainless primary heat exchanger is the low nox version. The rest are all alumized primary and stainless secondary.

 

[Cropduster172]

Only Payne furnace with a stainless primary heat exchanger is the low nox version. The rest are all alumized primary and stainless secondary.

Check yourself.
Don't have a secondary. Single stage...nice and simple. Stainless heat exchanger.