Leaking Heat Exchanger Replacement of a Noritz NR98OD Tankless Water Heater

How to replace a leaking heat exchanger on a Noritz NR98OD outdoor tankless water heater. This 4.5 years old tankless water heater had developed a heat exchanger leak. Luckily most tankless water heater manufacturers warranty their heat exchangers for 10 to 15 years. In this case, Nortiz has provided us with a new replacement heat exchanger, blower fan, and a gas manifold. If you wondered what it will take to do this work yourself, please watch this video.
Please, support my channel by giving me a like, subscribing to the channel, and hitting the notification bell.
Tools needed for this procedure:
1. Screw Driver with Magnetizer - amzn.to/3JSdzgi
2. My favorite pliers sets:
- Single Pliers Medium Size - amzn.to/3sZfwBc
- Two Pliers Set, Medium & Large - amzn.to/3znkMQC
- Three Pliers Set, Small, Medium & Large - amzn.to/3pMuyII

[@earthsign28]

Do the o rings have to be replaced Everytime you disconnect the heat exchanger pipes?

[@GJ-cz4bs]

Hi Dennis, Very nice job and neatly done. I have a NRC98-OD and recently replaced the thermal fuse. But now when i use my master bath hot water and my shower head hot water at the same time the water turns cold. Noritz wants me to check the gas pressure with a Manometer. I don't see any water leaking anywhere. Any ideas on what could be causing this? Thank you!

[@jason8795]

What would cause a foghorn sound on cold startup with this unit? Great video by the way. Thank you

[@DavidTPhan]

The instruction said "Please make sure to adjust the manifold gas pressure after replacing the manifold plate..." but I did not see you did that? any reason why you just put the screw back without doing any adjustment the gas?

[@peterkim2746]

It is a great video. I'm having a leak and error code 51 was displaying on the remote. I opened up and saw leaks. I can't tell whether it is from the heat exchanger or manifold plate. Is there a way I can tell just by looking?

[@dodabartman123]

just the other day, I got a #5 error code on my Nortiz NRC98-DV. It's been running for 9 yrs now. I have reset it several times and it comes right back, and will not it fire. Should I replace the gas manaifold for $150 - $275, or could it be something else like water in the line? At this age does it make sense to replace the whole heater for $1k

[@LaKeRz2416]

Nice job! But replacing heater all together for a new one could be a better idea. Cost of the replacement parts and professional labor like shown are very close to a new replacement unit price.

[@kdcarver]

You missed his comment that Noritz warrants the exchanger for a decade to twelve years. They send you the part for free. A new unit is $1300 - $1800. No brainer - replace the exchanger.

[@christopherwilson2606]

I almost always replace the entire unit if it requires a new heat exchanger. Too many things can go wrong when replacing heat exchangers for any make or model. If a few bucks are all that matters to a customer, I'd almost always move on... time is money.

[@yatusabe2537]

Need help. NR83-DVC leaking. It’s a slow leak, but hasn’t stopped for a couple days.

[@7jack7]

Noritz, they may not last long but they're expensive.

[@filmart430]

Where are you located and if local, how can I get in touch with you for service?

[@dodabartman123]

Great Video Dennis the Plumber, you are a man who knows his way around the Noritz Brand. I wish you were near Virginia. I'd hire you in a second..I have one of these models that worked flawlessly for the first 4 years. Then I started getting a boom sound during startup. I cleaned the igniter and cleaned the fan, could this be a sticking manifold solenoids? Also my water sometimes goes from too hot to cold. Is that probably the thermal fuse? Thanks Bart

[@dennistheplumber]

Hello Bart! What is the model number of your water heater? The condensing and the non-condensing models are serviced/repaired in a different way. Let me know and I will share my opinion with you.

[@dodabartman123]

@@dennistheplumber NRC98-DV

[@dennistheplumber]

Ok, if this sound comes out when the water heater initially ignites and is something close to a low vibration, this is due to burner air channels blockage. See if the burner of your water heater could be pulled out and cleaned with a compressor and air stream under pressure. I have a video for Rinnai maintenance which in the last section shows how it is done on Rinnai. The procedure will be very similar on your water heater as well.

[@dodabartman123]

Will do, thank you very much Dennis!

[@asaholey]

Replacing the heat exchanger involves unscrewing hundreds of screws, and it's frustrating to see such poor design from big companies like Rinnai, Noritz, and Navien. I lived in Taiwan for over ten years, where my no-name tankless water heater required no maintenance and worked flawlessly straight from the pipe. However, after just five years in Canada, my Noritz unit, despite being used with a water softener, is already leaking. It's disappointing that these renowned brands are selling such poorly designed products.

[@arsuay-brains]

Which city you do service?

[@pablotelford6788]

What lubricant did you use when you put the new thermistor O-ring?

[@dennistheplumber]

It's the Plumbers' Silicone Grease amzn.to/3MBqIKZ

[@TheAmonsivais]

Hi Dennis! Great video. Question: I have three Noritz tankless (2 indoors + 1 outdoors) that are ~11 years old. One indoor unit started to leak from the P/N SKG7767 Heat Exchanger Drain Pipe after about 5 years and now the second indoor unit started to leak from the heat exchanger drain pipe yesterday. Both times immediately following annual system flush with vinegar. Have you seen this before? Is the drain pipe difficult to replace myself since it's out of warranty? Thank you!

[@dennistheplumber]

This sounds like a heat exchanger leak caused by the flush. Yes, sometimes if the flush is done with the chemical solution rather than vinegar, the heat exchanger gets agitated to a point of leakage.

[@TheAmonsivais]

@@dennistheplumber Thank you! Yes, Unused vinegar. Is the drain pipe something I can replace myself? It looks like it's held in place with clips.

[@TheAmonsivais]

I meant I used vinegar. The drain pipe is definitely leaking. I could see the fine stream.

[@dennistheplumber]

It’s hard to guess what exactly the issue is. Call technical support and let them know you are handy. They will walk you through.

[@pwnagejetsonjetson4118]

my noritz tankless started leaking right after a flush, did you ever figure out the problem?

[@robertredfern5515]

I just install navien they are far superior to Noritz

[@arif-budiman]

28:53 What type of grease are you putting here?

[@dennistheplumber]

It's called plumbers grease. Available at Home Depot.

[@arif-budiman]

@@dennistheplumber Thank you!

[@lonakanalimasa3139]

The gas rod lifts!😮 you're a bozo