Researching a tankless water heater upgrade often means digging through scattered forum threads, manufacturer pages, and old reviews just to find answers to basic questions. This roundup pulls together the fifteen questions buyers ask most often about the RU199iN and its current replacement models, in one place.
The Rinnai RU199iN was discontinued by Rinnai in September 2024, with the RXP199iN and RX199iN serving as its current direct replacements, both offering the same 199,000 BTU capacity with updated features including indoor/outdoor installation flexibility and, on the RXP199iN, a built-in recirculation pump. Below are the fifteen most common questions buyers have about this model family.
1. Is the Rinnai RU199iN still available to buy new?
No, it was discontinued by Rinnai on September 4, 2024. New buyers should look at the RXP199iN or RX199iN as current replacements with equivalent or better capacity and features.
2. What replaced the RU199iN?
The RXP199iN and RX199iN are Rinnai’s current models in the same 199,000 BTU capacity class, both offering indoor/outdoor installation flexibility that the original RU199iN generally lacked.
3. What’s the difference between the RXP199iN and RX199iN?
The main difference is the built-in recirculation pump included on the RXP199iN, which reduces hot water wait time, the RX199iN does not include this feature built in.
4. How much does the RXP199iN cost?
Pricing varies by retailer, current pricing has been observed around $1,735.53 on Amazon, though always check current listings for accurate up-to-date pricing.
5. What size home does a 199,000 BTU unit support?
These units are generally sized for larger households or homes with high simultaneous hot water demand, consult a proper sizing guide based on your specific fixture count and climate.
6. Do I need a bigger gas line for this unit?
Often yes, these units typically need a 3/4 inch gas line minimum, though exact sizing depends on total home gas demand and should be confirmed by a licensed professional.
7. How often do I need to descale the unit?
Rinnai recommends annual descaling for most households, more frequently in hard water areas to prevent scale buildup on the heat exchanger.
8. How long do these units typically last?
Generally 20 years or more with proper maintenance, notably longer than a standard tank water heater’s typical 10 to 15 year lifespan.
9. Can I install one of these units myself?
Technically possible for someone with strong gas, plumbing, and electrical experience, but most manufacturers require professional installation for full warranty coverage.
10. What does professional installation typically cost?
Real-world quotes vary widely, ranging from roughly $2,500 to $9,000 depending on whether it’s a straightforward tankless-to-tankless swap or a more complex tank-to-tankless conversion requiring gas line and venting work.
11. Are there tax credits available for these units?
Check irs.gov and your state energy office directly for current program status, since eligibility and credit amounts change and should be verified for your specific purchase year.
12. Does hard water affect these units?
Yes, hard water accelerates mineral scale buildup on the heat exchanger, making regular descaling and potentially a water softener more important in hard water areas.
13. Can these units be installed outdoors?
Yes, both the RXP199iN and RX199iN support indoor or outdoor installation, a genuine upgrade over the RU199iN’s largely indoor-only design.
14. What should I do if my unit shows an error code?
Check the specific code against your unit’s manual or Rinnai’s documentation, many codes have a documented first-step homeowner action before requiring professional service.
15. Is upgrading to a current model worth it if I already own an RU199iN?
If your existing unit is functioning well, there’s no need to replace it immediately, but when it does need replacement or major repair, the RXP199iN or RX199iN are the logical upgrade path with improved features.
Rinnai RXP199iN Condensing Tankless Water Heater with Built-In Recirculation Pump - View on Amazon
The Bottom Line
The RU199iN’s discontinuation doesn’t leave existing owners stranded, and buyers researching this model family today have two strong current replacements in the RXP199iN and RX199iN, both offering the same core capacity with meaningful feature upgrades.
Frequently Asked Questions
Is the RU199iN discontinued? Yes, Rinnai discontinued the RU199iN on September 4, 2024, current buyers should consider the RXP199iN or RX199iN instead.
What replaced the RU199iN? The RXP199iN and RX199iN, both offering 199,000 BTU capacity with indoor/outdoor installation flexibility.
Which model has a built-in recirculation pump? The RXP199iN includes a built-in recirculation pump, the RX199iN does not include this feature.
How much does installation typically cost? Real-world quotes range from roughly $2,500 to $9,000 depending on installation complexity and whether gas line or venting upgrades are needed.
How often should I descale my unit? Annually for most households, more frequently in hard water areas to manage mineral scale buildup on the heat exchanger.
What’s the expected lifespan of these units? Generally 20 years or more with proper maintenance, longer than a typical tank water heater’s 10 to 15 year lifespan.
Can these units be installed outdoors? Yes, both the RXP199iN and RX199iN support outdoor installation, unlike the largely indoor-only RU199iN.
Do I need a bigger gas line for a 199,000 BTU unit? Often yes, generally 3/4 inch minimum, though exact sizing should be confirmed by a licensed professional based on total home gas demand.
Are tax credits currently available? Check irs.gov and your state energy office directly, program terms change and should be verified for your specific purchase year.
Should I replace my working RU199iN now? Not necessarily, if it’s functioning well there’s no urgency, but plan on the RXP199iN or RX199iN when replacement eventually becomes necessary.
References
- SupplyHouse.com discontinuation notice for the Rinnai RU199iN, accessed July 2026: https://www.supplyhouse.com
- Rinnai official product specifications for the RXP199iN and RX199iN, accessed July 2026: https://www.amazon.com/s?k=Rinnai+RXP199iN
- IRS official guidance on energy efficiency tax credits, accessed July 2026: https://www.irs.gov