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Lennox SLP98V Furnace

3.1 of 5 stars 31 reviews | #10 of 26 Furnaces
Updated: May 3, 2019 | Read more about Lennox Furnaces | SLP98V Warranty

Overview of SLP98V

The Lennox SLP98V is a gas variable-capacity furnace with an efficiency rating of up to 98.7% AFUE. The SLP98V comes equipped with a self-calibrating variable speed inducer and a stainless steel secondary heat exchanger. It has dual-fuel capability, meaning it can be paired with a heat pump to provide increased comfort and efficiency. The variable-speed motor and advanced sound absorbing materials provide quiet performance. This furnace has earned the Energy Star Most Efficient 2015 label, which means it is both extremely efficient and prevents greenhouse gas emissions. When paired with an iComfort Wi-Fi thermostat, the SLP98V provides advanced scheduling and remote access via laptop, smartphone or tablet.

Furnace Filters for the Lennox SLP98V

Air Flow Configuration Cabinet Width Filters
Upflow / Horizontal All 1 16x25x1 filter
(side air return)
1 16x25x1 filter
(bottom air return)

Consumer Reviews of the SLP98V

  • Very Satisfied
    15
  • Somewhat Satisfied
    1
  • Neutral
    0
  • Somewhat Unsatisfied
    2
  • Very Unsatisfied
    13
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2 of 5 stars Hemingford, NE
Date created: 2019-05-03

Dissatisfied

We purchased the Lennox SLP98 in October 2013. The system did not function properly ran at extremely high speed and was very noisy. Lennox dealer tried several recommendations that Lennox made. The territory rep came to our home to help diagnose the problem. Several things were tried including making a larger hole is sidewall of the house for a larger PVC exhaust pipe. That did not fix the problem. In the end, that furnace was replaced with a new one. The original furnace was taken to the lab for diagnosis and we understand they could make no determination of the problems. Last month we discovered our carpet on other side of a wall of the furnace was wet. After a couple of days decided it must be coming from the furnace. Called dealer that installed the unit and upon his checking unit, he found a screw in the cold end header box that had corroded and rusted and was allowing the water from condensation to leak below inside furnace. This had to have been going for a loooong time because the inside of our furnace is rusted beyond words. At this point, Lennox is saying if we did not have annual maintenance there is no warranty. Really??? Who calls a repairman when thereís nothing wrong and donít need to pay for a service call, just because. We were never told that we need, must, should have an annual checkup on the unit. Why?? What was happening in the furnace is not visible, just like a plumbing leak behind a wall that you canít see until it becomes a bigger problem. We are very upset with the situation and only wish reviews on this had been available when we purchased ours, but this model was a recent release at that time. We have read other reviews with problems with the header box, but have not yet seen similar ones to our problem. We will post our issue on as many places as we can to get the word out. Lennox will find every way to not have to back their product. We thought Lennox was a reputable brand and thus purchased their product, never imagining we would find ourselves in this position. The 10-year warranty has no value. If you are looking to replace your home HVAC system do not consider Lennox as many reviews indicate many problems with this model and others. We only wish we could upload pictures of all the rusted components inside the furnace. We truly donít know if the system works properly. We sure have not seen the energy savings results that were a selling point.

5 of 5 stars Ontario
Date created: 2019-01-15

Lennox

We installed a new Lennox furnace in the fall of 2018. The unit is very quiet, gets heat to all areas of the house and is more efficient than our old single stage furnace. We love that you don't hear the furnace coming on and going off. It just quietly keeps the house at a comfortable temperature.

1 of 5 stars Media, PA
Date created: 2019-01-11

Chronic problems and horrid service

Purchased this unit (most expensive high efficiency they sell) January 2015. Within a month we began getting error code 292 about every 6-8 weeks. This error is presumably reported failed blower motor, but, the blower motor is actually ok, so it is a design glitch of some sort. This error turns off the system requiring a power off and on to reset it. This has now gone on for the last 3.5 years, and the dealer has replaced the motor, several different sensors and probes, and logic board. None of this has fixed the problem. I have included photos of the most recent two occurrences to prove my point. I finally went to Lennox customer service. They wrote to me and asked for all the records for verification, I sent these. However, they then passed it to their local technical rep. He emailed me once with a phone number, but when you call that number you get an "out of service" message. He also has not responded to three subsequent emails. I have now written back to Lennox, and they are not replying to my emails. In addition to this chronic and unresolved problem, the unit has also had several other component failures, a pressure switch and refrigerant loss, all within three years of the install. Lesson: Lennox products should be avoided because they are unreliable, and when service is needed they run you in circles and eventually ignore you. I plan to file a complaint with the consumer protection agency but am also writing reviews on as many sites as I can to warn potential customers. Stay away from Lennox!!!

1 of 5 stars Overland Park, KS
Date created: 2018-11-15

Furnace did not perform as expected.

Lennox SLP98 98% furnace replaced a Lennox Elite 80% furnace with exhaust through the roof. The new Lennox is now 8 months old at the time of this writing. Neighbor complains about gas odor coming from the furnace exhaust on the side of our house. Gas company came and found high levels of carbon monoxide (500 - 600 ppm) at the exhaust each time the furnace was starting up. An HVAC dealer came and verified the high levels of carbon monoxide 500 - 100 ppm in exhaust pipe 2 feet from furnace at startup. Another dealer said that it was normal for Lennox Signature SLP98 furnace to have high levels of carbon monoxide (500 - 1300 ppm) in exhaust at startup. We did inform the Gas company that these high levels were normal for the Lennox Signature furnace, so they could inform everyone at the gas company. After 5 minutes of running the furnace, the carbon monoxide levels off to around 28 ppm. I would not have bought this furnace if I would have known about the high carbon monoxide levels coming out of the exhaust at the side of the house at ground level. After the furnace was installed, we kept the thermostat temperature settings the same as before. With weather being similar in previous years, our gas and electric bills have greatly increased with this new furnace during the heating season. Bottom line is, this furnace is way too expensive and does not perform as advertised. Do your research and buy a different brand or model.

1 of 5 stars Voorhees, NJ
Date created: 2017-01-15

Pressure switch fails every year

This unit was purchased to replace an old Lennox Pulse furnace which was very reliable but noisy. The new furnace failed the first time when it was just one year old. The pressure switch was the problem and the pressure switch has failed every winter. Each time was on a weekend and the technician couldn't get the part until Monday leaving us without heat for a couple of days. When the furnace works it is very nice but the reliability is totally unacceptable.

1 of 5 stars Vancouver, BC
Date created: 2016-12-02

Cheap Furnace, ridiculous parts price

So Lennox sells cheap furnaces, then they charge you twice or 3 times the amount for parts when it needs maintenance or repair. Go on their website for your local dealer and you'll find no phone contact number. You have to have an account with Lennox and they only give accounts to HVAC companies, which means they have strict control of their parts and will charge you to death. My furnace repair technician said every customer he had with Lennox furnaces hates it and will never buy it again.

5 of 5 stars denver, co
Date created: 2016-05-10

Energy efficient

I've had my furnace for roughly 3 years now. The furnace is a lot more efficient than my old one. A lot smaller. And it is quieter. It feels a lot more comfortable heating my home and maintaining a certain temperature. I've never had to repair it, just basic maintenance. Yes I would buy another Lennox furnace and refer one to a friend.

1 of 5 stars Denver, CO
Date created: 2016-04-14

Lennox blower inadequate for house

Purchased a Lennox furnace despite bad reviews on this site. I read the reviews, thought "Well, they're talking about radiator & heating-oil type furnaces, not gas-heated forced-air furnaces, so Lennox will probably be all right..." Huge mistake! We've only had the furnace for 3 weeks, in spring weather. The blower fails to circulate air in tri-level house. The temperature at the thermostat (ground level) reads within parameters, so the basement freezes while the upstairs roasts - & the blower fails to function when we attempt to start it manually. If/when it does run, it doesn't even put out enough air force to push a paper tissue off of the floor heating vents! Bitterly regretting this terrible decision - wish I'd gone with Amana instead!

5 of 5 stars Johnstown, NY
Date created: 2015-11-06

I recently upgraded my furnace for the first time in 30 years

My father has had the same furnace in our family home for many, many years and it was costing him a ton to maintain in the winter. One day when the Niagara Mohawk service men were in my neighborhood updating all the meters in town, they informed him that his furnace was simply too old and sucking energy and not to mention money! I went online and tried to find a decent gas furnace. While the price was very steep, we were able to come up with a payment plan and we were told that our 3 year savings on our bills would cover almost 1/4 of the furnace cost. We haven't used it too much yet (my father doesn't like to turn on the heat until it's extremely cold outside) but we did test it out a few times! It also takes up much less space in the basement, and is nicer on the eyes. It works wonderfully and we are looking forward to staying warm and saving money this year.

5 of 5 stars Fort Worth, Tx
Date created: 2015-10-09

Lennox Gas Furnace Review

The reputation of Lennox is what initially sold me to their product. The pilot light on our old furnace kept going out, and those dangers/annoyances bother me extremely. My husband purchased the Lennox after careful review/talks with family and friends. There was not a single doubt in our mind about this purchase. We ordered it and the gentlemen who installed it were exceptional. What surprised me were the many options available to fit our schedule. Also, the furnace is so quiet and keeps a steady temperature, allowing our gas/electric bills to decrease drastically. I would recommend this to anybody looking for a new gas furnace.

5 of 5 stars Huntsville, AL
Date created: 2015-10-02

Initial impression

On Monday, the dealer replaced a 1991-era furnace with the highest efficiency Lennox gas heater that would fit in the 17" closet. Slightly larger than the old unit, the installer ran into a problem with the utility closet door and I told him, ďThat door won't keep us warm this winter but the heater will. Do what you need." They got some lumber and fixed the door afterwards. I love the PVC exhaust pipe and they installed a new drain line for the condensate. That water means significant wasted heat is no longer going up the flue. We also had the non-functional evaporator removed so it is a heating-only unit. The installer put in a metal duct extension, which was a struggle in that tight space. Bought through Costco, our discount comes via a rebate to our membership card, easily 10% off. Thursday night the temperatures are in the low 50's and the house is wonderful. This Lennox unit is quiet and the low-speed mode maintains a 'wife comfortable' temperature. As for savings, the electronic ignition solves the summer utility bill, had $10 for the pilot light. My only concern is the air inlet is from the closet. I would have preferred an outside or attic source. But it is PVC and I can handle it like I had done with the former furnace. We also had the filter located to the hallway inlet, making it much easier to replace. With clean filters and no evaporator, this unit should easily handle what cold winds blow.

5 of 5 stars Denver, CO
Date created: 2015-09-28

Efficient furnace from a reliable brand

I had to replace my gas furnace last November due to consistent problems with my old one's pilot light going out. After several repairman visits, they were unable to permanently fix the old one. I ended up deciding that another bargain-brand model simply wasn't worth the hassle, and went with a Lennox. Installation appeared to be relatively simple (although, I have to admit, I didn't perform the install by myself - I hired a local crew). Not only has this model performed significantly better than out outgoing furnace (no outages and, thus, no having to relight in the middle of a cold winter night), it has saved us nearly $10 per month on our gas bill since being installed (I know it doesn't sound like a lot, but that's like saving 5 quality cups of coffee per month). Efficiency and reliability are the best ways to measure the quality of a furnace. In this regard, the Lennox model we purchased aced both categories. I would certainly purchase this model again, but I doubt I'll have to anytime soon.

5 of 5 stars Oklahoma city
Date created: 2015-06-05

Lennox gas forced air furnace

In general, the SLP98V variable-capacity gas furnace has good performance, it's easy to install, it's great unit for the do-it-yourself type of person, and it is a very quiet running hot air furnace. It has plenty of forced air power and delivers plenty of heat quickly. I mostly only buy Lennox products, because the quality of the brand is familiar to me but also it is good quality. When buying a furnace, the most important things are if it works well, how pound it is and the price. So far I am impressed with all three of those things. I installed this a little over three months ago, and it's does a wonderful job. I have a rental house as well and I am going to be replacing the furnace that is over 10 years old with the Lennox model. I would recommend this furnace .

1 of 5 stars Richmond Hill, Ontario
Date created: 2015-02-22

Not reliable

28 months old, 3 repairs. This latest breakdown happened on the coldest day of this winter, -26 C. It went cold turkey at around midnight. Thank goodness for portable heaters (3 of them on hand, just in case). It was the pressure switch. It cost $257. There goes any possible saving on a high efficiency furnace compared to my old 20-year-old standard that had never been repaired. True. On the positive side: it is quieter.

2 of 5 stars Surrey, BC
Date created: 2014-11-12

Not reliable

Our 3 year old furnace quit heating. Parkinson's Heating responded quickly and replaced a vacuum switch. The part is under warranty but labor is only covered for 1 year. The money you save on gas is more than spent on the cost of the furnace and paying for repairs. We would have been better off keeping the older, less efficient furnace. Lennox needs to do a better job of standing behind their products.

5 of 5 stars Freeport, MN
Date created: 2014-03-14

SLP98UH SERIES,VAR.CAP.GAS.FURN

This unit was installed in Oct. 2013, so there is not much info to go on. It performed as expected during this winter's very cold weather. I have not been able to determine how efficient it was compared to my old furnace, which was 25 years old. I am hoping that with the dual-fuel rate for electricity, that it will be more economical in the long run.

1 of 5 stars Toronto, Canada
Date created: 2014-02-24

Avoid at all costs

Stay away from Lennox SLP98UH110xv60c-03 unless you want to be woken up in winter with a high pitch noise throughout the house. Dealer checked on it and said, everything is alright, nothing they can do. Furnace is less than 2 years old. Very frustrated! Followed up with Lennox directly, 2 months later, no reply. $4,000 wasted on a piece of crap!

5 of 5 stars Grand Blanc, Michigan
Date created: 2014-02-05

The best furnace ever

We have a 2,800 sq-ft two story house in Michigan. We built this house in 1992 with a reputable builder. He installed a Carrier Weather maker 100k btu furnace 90% and a 4-tom a/C. The furnace has worked fine and four years ago, we replaced the high temp sensor and then this x-mas the gas valve (on Jan. 1, 2014). However, all these years our house had temp difference of anywhere between 2 to 5 degrees between upstairs and downstairs - hot in summers and cold in winters. Also, the furnace would make a rather loud noise when it would kick on you could certainly hear the blower even though I sleep upstairs, it kept waking me up in the middle of the night. Since the unit was 22 years old and it kept making so much noise, I decided to shop around for a new high eff furnace. I read all of these reviews on this site and got estimates for Trane, Carrier, Lennox, and Bryant. At the end, I went with the slp98v and xc- 18 ac with icomfort. The furnace was installed three days ago. This furnace is simply outstanding. First, I cannot even hear it when it turns on because of the var-speed blower - it is absolutely quiet when in normal mode. Second, we no longer have temperature difference between upstairs and downstairs. I am not making this up - the furnace produces very consistent heat in every part of the house. Third, we had a central humidifier (Honeywell) which I kept. But, the installer took out the humidity sensor that came with Honeywell and just hooked up the wires to the furnace since it has its own internal humidity sensor. We can actually control the humidity from the thermostat now and I do not have to go to the basement each time I want to change the humidity. Fourth, the t-stat (iComfort) has tons of very useful features not to mention I connected it to the internet and I can control it via my iphone. Fifth, this unit is 98% efficient which in mi qualifies for close to $500 rebate from the utility company. Also, Lennox was running a special and we will get a huge rebate for this unit. Lastly, we used Terry Allen to purchase and install the unit and they offer 5 years labor and 2 years free maintenance to go with the 10-year parts warranty of this unit. So far so good and I love this unit. I will certainly let people know if something should happen. The only minor concern is the price - but we were looking for something high end with variable speed and communicating system and when compared with the other units we considered, this package came out much better.

1 of 5 stars Leesburg, VA
Date created: 2014-01-30

Unreliable

23 month old unit stopped working during 2014 Polar Vortex. Pressure switch failed. 5 days to get new part installed. $250 out of pocket expense. Have read about others with same problem with this unit.

1 of 5 stars Winnipeg Canada
Date created: 2014-01-09

I finally pulled it out

The Lennox slp98 that I purchased 3 years ago is now pulled out and replaced with a different model. It never worked properly from day 1. It took them at least 2 weeks to get it operating more than a hour at a time. Afterward, it would just shut-down once or twice a week for an hour or so or sometimes never come on again until a service tech got it running again. I had two portable heaters on stand-by all the time. The last month with a different reliable furnace has been a blessing. It can get to -40C where I live.

5 of 5 stars Erie, PA.
Date created: 2013-12-05

Dave Lennox Signature Collection Gas Furnace

This furnace gives a nice even heat. It is so quiet that you don't realize it is on. I'm very happy that I purchased this furnace.

1 of 5 stars Norhern Michigan
Date created: 2013-11-09

Howling Noise at All Fan Speeds

I have two new SLP98V just installed. They both make a quiet howling (harmonic) noise which is much more annoying than the blowing noise that my old Amana made. The Amana was replaced to get the improved air purification system and computerized thermostats with smartphone link. The other unit was replacing an older broken furnace. Service guys are very nice and are working with Lennox to "fix the problem". One entire unit was replaced already, quieter but still howling. So far, no real improvement. At high seed, the fan is as loud or louder than my previous furnace (which wasn't that loud). There is also a pipe tapping noise when the gas valve opens and closes. If they can't "fix" it, I will reinstall the Amana, add an aftermarket MERV 16 air filter and give up the cool thermostats at considerable financial loss. Lennox does some pretty aggressive advertising about how quiet their furnaces are but you just never know. Good luck with your purchase.

1 of 5 stars Anchorage Alaska
Date created: 2013-09-27

SLP98DF070V36B

Heater continues to fail. Stopped working again after service call of less than a month. Heater has not worked for more than 6 months without a malfunction.

5 of 5 stars LONGMONT COLORADO
Date created: 2013-06-16

Lennox Dealer

I have installed several SLP98Vs, not a single problem with the furnace. Our customer love it, some of them have 2 in their home. Lennox engineering is great and they stand behind their product. They will even have a field consultant to come and check the furnace or A/C, if there is a problem the tech cannot find. The installation is the most critical point of a furnace working properly. Most of the installation, we see the furnace is over sized and the duct is too small. Every sale should be provided with a load calculation for the home. The duct system, and the airflow should be checked to determine how well the new system should perform.

5 of 5 stars Birmingham, AL
Date created: 2013-06-13

Excellent Furnace!

This furnace does exactly what it says it will do. My heating bills dropped like a rock. I never hear it run and my home stays comfortable with even temperatures all winter. One note to Ted who had problems with pressure switches. Check to make sure the furnace is vented correctly. The SLP98V is a direct vent furnace which means the vent pipe for both the exhaust and the intake should be the same length. Other Lennox 90+% furnace are indirect vent furnaces, meaning the intake vent does not have to run the full length. An imbalance can cause pressure switch trips, which easily could be diagnosed by a technician as a bad switch. I am a bit confused though, because you should have had a labor warranty to go with your 10 year parts warranty. Should that not have eliminated your costs? Who installed your furnace? Was installed by a Lennox Premier Dealer? Full disclosure - I work for a Lennox Premier Dealer. I purchased and had this furnace installed in my home so my review is a personal review. That said, I have some insight to some of the issues we encountered. Mine was the first one we installed in this market.

5 of 5 stars Winnipeg, Mb, Can
Date created: 2013-05-11

Lennox is Awesome!

Most gripes seen more centered around bad service issues and installation. SLP98V I put 1 in my home, silent operation. 100's installed, yes bad icomforts + 1 out of 25 defective air switches. Lennox resolved, no problems since. Unfortunate that dealers don't bother to train their staff how to troubleshoot and install properly that is the only major problem I see. Excellent engineering by Lennox on these new units.

1 of 5 stars Ontario, Canada
Date created: 2012-12-28

1.5 year old, Pressure switches failed, cost $400, Lennox refused to help

1.5 yr old, pressure switches failed, called Lennox, no backing of the failed product whatsoever, read the fine print, fixing cost over $350+half day off work - very very disappointed.

5 of 5 stars Scarborough Ontario
Date created: 2012-08-31

Lennox Furnace

We had installed lennox slp98 high efficiency furnace for 2 years and it's very quiet furnace, it work very good condition, save a lot of money compare to my old Lennox Furnace. It's 98% High efficiency, and it was top of rate on the market. We are very satisfied for Lennox Furnace that we have been used for 30 years.

4 of 5 stars Binghamon, NY
Date created: 2011-11-26

My lennox SLP98V furnace

I've owned my furnace for about six months. It's reliable, quiet, and works well for the most part. It gets pretty cold where I live so having a reliable furnace is important to myself and my other roommates. It's quite efficient and my heating bill last month was as low as it's ever been. It was reduces approximately 10% compared to our older furnace that was replaced last winter. Now that summer is here, our cooling costs have also gone down by the same 10%. It had to undergo one repair because it was not installed correctly, but this was taken care of by the people who installed it within the same week. It sometimes runs a little loudly as well, especially at night when the house is quiet. I would buy this brand again because of its great energy efficiency and overall quality, despite the few issues we had with it.

1 of 5 stars Surrey BC
Date created: 2011-05-21

LENNOX SLP 98...IS IT 97% EFFICIENT?

I had an slp98 Lennox furnace installed in Oct 2010. It's supposed to be Lennox's latest and greatest furnace! I was told it was 97% efficient, a big difference form my Airco which was rated at approx 60% efficient. I expected to see a huge difference on my gas bill and even called Teresan (at the time) to figure out how to change my equal monthly payments! However, I have not seen 'any' difference on my gas consumption. Even considering our winter. I should see some savings when there is a 37% efficiency difference, shouldn't I?? Also, what worries me even more is that this new furnace 'booms' or has mini explosions periodically while ramping up to speed. The installer has guaranteed me that it is not a gas leak or seeping gas (although he has not come and to check because I have to give him a specific time when the "booms" occur) but perhaps my air ducts expanding!? Really??? Do you think I am an idiot and don't know the difference between the two sounds? At this point I am not happy with the furnace or the service I've received to attend to my concerns.

5 of 5 stars
Date created: 2011-02-04

Best purchase I have ever made

I was an installer for lennox for a couple of years and I have now totally changed careers but that is besides the point. My slp98v furnace is the best purchase I have ever made, it runs great and never know its even running. I am a strong believer of lennox products and lennox only because to me they are built the best and lennox I feel is always one step beyond everyone else. now a furnace is much like a new vehicle on the market, if you buy something that is brand new and they havent yet been able to work out any of the kinks in the model you may have problems but that is a risk you must take to get quality and reliability! Best part is if something breaks on a new model and it is to do with a fault, it will be covered by warranty. so dont complain and relax you people.

Other SLP98V Reviews

A consumer consults hvac-talk.com about choosing between a Lennox SLP98V, a Coleman unit and a Rheem furnace. He has received quotes on each of these furnaces. One contractor recommends the Rheem product; the other comments seem favorable toward the Lennox furnace based on the ease of servicing, small footprint and positive feedback from customers.

A homeowner asks for comparison between an Amana furnace and the Lennox SLP98V, as he is considering which one to install. An expert replies that Lennox is a more reliable brand, in his experience, and bases his recommendation upon that.

Another question is posed about the Lennox SLP98V on justanswer.com. An HVAC expert discusses that it is a modulating furnace, which is more expensive than a regular furnace but generally provides more comfort. The expert feels that Rheem offers a superior modulating furnace, but there are no negatives associated with the Lennox product. Overall, the feedback on the forums seems to relate that the Lennox SLP98V is a worthwhile furnace to own.

Question and Answer

Question:

New Lennox SLP98v unit is flashing the code A375. Any idea what that means?

Answer:

According to the Installation Manual for the Lennox SLP98v the diagnostic code of "A" is displaying the Cubic feet per minute (cfm) setting for indoor blower (1 second ON, 0.5 second OFF) / cfm setting for current mode displayed.

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Lennox SLP98V Model Numbers

The SLP98V is available in different models which vary in efficiency and capacity.

Model Number AFUE BTUs per Hour
SLP98DF070V36B-* 97.5 66,000
SLP98DF090V36C-* 97.5 88,000
SLP98DF090V48C-* 97.5 88,000
SLP98DF090V60C-* 97.5 88,000
SLP98DF110V60C-* 98.2 110,000
SLP98UH070V36B-* 97 66,000
SLP98UH090V36C-* 98 88,000
SLP98UH090V48C-* 97.5 88,000
SLP98UH090V60C-* 98.2 88,000
SLP98UH110V60C-* 97.5 110,000

SLP98V Warranty

Lennox provides a lifetime limited warranty on the heat exchanger of the Lennox SLP98V. Parts are covered by a 10-year limited warranty. An extended warranty is also available for purchase at the time of installation.

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