Green Options › Eco Friendly Green Products › Eco Friendly Home › Appliances › Water Heaters › Demand/Tankless Water Heaters › Rinnai Tankless Water Heater Model 2532

Rinnai Tankless Water Heater Model 2532


Pros: Endless hot water, Cheaper to run

Cons: Seems to take longer to get hot water flowing, Expensive

When we built our new home we opted for the Rinnai option that the builder offered. It was about a $2,000 option and we didn't install it ourselves, so that's why I left off the price since it can probably be had for less if you contract straight to the vendor.

The system has been great with no complaints. Our gas bill is about $8 in the summer when we are only using the Rinnai (no gas heat in use) and I think that's pretty good. We are a family of 4 running the washing machine at least twice a week as well as dishwasher 2 or 3 times a week. We bathe too.

If I had to find something to complain about (aside from the cost) it would be that it takes a solid 40 - 50 seconds to get hot water coming out of the tap (assuming it had not been in use for a while, like in the morning). I have been told this could be solved with a circulator pump, but that dissolves the efficiency of the Rinnai. I have also been told that it could just be the plumbing layout of our home. Regardless, it still seems a bit longer than is should take.

The system does seem to work as intended, providing endless hot water, there have been several instances of the washing machine running as well as a shower and a bath tub with no flux in hot water (water pressure is a different story, but no fault of the Rinnai).

Our unit is mounted in our garage next to our furnace. It's facing dimension is about that of a microwave door, and only sticks off the wall about 5 inches, so it is tiny, especially compared to a traditional hot water heater.

All in all, it's a great system, works as intended and if you can live with the cost as well as waiting a few seconds for hot water, this is for you.


Pros: You will not run out of hot water

Cons: Initial High Cost & Requires Maintenace

I purchased my system about 5 and 1/2 years ago when I had my house built. The water heater failed yesterday. No power comes to the unit that controls the temperature setting.


Called the plumber who installed it and he will be coming to fix it tomorrow. He told me that his other customers also have a similar failure and it was due to the controller board going bad.


Not sure how much it cost but I assume it is going to be pricey. The blower part has a 12 years warranty. Not sure if the controller board is under warranty.


Will update this review once I get it fixed.




Pros: Always have hot water! Lower operating costs

Cons: I don't have any to add

We are a family of four with a lot of laundry, showers and guests. I have never had an issue with our Rinnai. I felt like I was on the cutting edge when we built our home 7 years ago and installed this "water heater with no tank". I feel like the little extra it cost at the time, was well worth it. I used to have to fill my garden tub only at night so that everyone could take showers at our old house. I never worry about it anymore. I personally can't imagine going back to a conventional water heater. You are paying to heat water that "you might use" today, but then again, maybe tomorrow!

It is well worth the investment!!!


Pros: very efficient, plenty of hot water

Cons: Paid 1600.00, failed short time after 5yr warranty expiration, should have purchased conventional gas water heater,would have lasted 20yrs .

I purchased the best, paid the most money for the technology and advertized reliability of 15 to 20years. I received great efficiency and reliability until the 5yr warranty expired along with the unit. Hindsite being 20/20 is telling me I should have purchased a quality conventional gas water heater for 1/3rd the cost that would have operated it's 20yr designed lifespan with no problems.


Pros: $ave $$, $ave the Earth, Endle$$ Hot Water

Cons: Everything has to be coordinated at the installation

My home is over 20 years old. I researched alternative solutions to the tank water heaters when I planned to replace the failing unit in my 2200 sqft home.  After receiving bids, and interviewing, several local approved Rennai installers I chose a plumbing company I'd used before (with good results).  They informed me that I needed to coordinate with an electrician, the local gas company, city inspectors to pull permits, and their workers to get everything coordinated, or they could act as the general contractor and do that for me for a couple hundred bucks more. 


I decided to do the coordination work myself.  I called the city to let them know I was changing out my water heater and answered all their questions about timing and completion dates.  I called an electrician to wire up a box for power (based on specs from the plumber), and I called the local gas company to run a larger gas line to support the higher gas demands needed for the Rennai unit. I also emailed Rennai to get a list of certified Rennai installers in my area.( VERY IMPORTANT!!!)


I also had a choice to install the Rennai inside in the closet where the tank water heater was removed (more $$ to vent through the attic), or on the outside of the house. (I live in NC, winters can be below freezing for a few weeks.)


I decided to have the unit installed on the outside of the house between my daughter's bathroom, the utility room and the kitchen.  I also had to install a freeze protection kit that dumps out any water in the Rennai if the power goes out.  It is also required for outside installations to keep your warranty valid with Rennai.


Our Rennai was installed mid-December 2009, in time for the tax credits. (NOTE:  if you do not have a large enough tax liability (Let's say you owe Uncle Sam 0 dollars in the tax yerar) the credit cannot be taken. It's NOT a rebate.


Anyway, we love our endless water.  My gas bill every month is half of what it was last year. The master bathroom is on the opposite side of the house, so it does take a few minutes to clear the pipes of the unheated water sitting in them, but I can shower as long as I want even if the dishwasher or waching machine are also running.  $2850 I paid was for the Rennai 2532, installation, local permits, and freeze protection system.  I paid the electrician and the gas company separately.


The return on investment (ROI) is a little less than 5 years, at that point, the unit will have paid for itself.(I plan to stay here for the rest of my life!)


Hope that helps!


PS - Piedmont Natural Gas is offering a $250 rebate for residential customers for installing energy efficient natural gas tankless water heaters, for more information on this go to




Pros: Designed for tankless applications-durable

Cons: pricey

There is a product that will recirculate water and is for use on tankless applications, it will not void the warranty and will only add a few pennies to the cost of heating water.  It is manufactured by Metlund, can be seen on my website, may be able to contact a local supplier for this product.  go to and look at products-metlund.




Pros: 1 local business/plumber

Cons: Never returned with an estimate!

Contacted the only authorized local business/plumber for a estimate and he never contacted me with any of the methods I provided him. Email; work, home phone; and residential address.


Pros: endless hot water

Cons: cannot think of one

We installed two of these when we built our house three years ago.  Paid around $1200 each.  Cost savings for use and reliablity are incredible.  No problem yet.  One reviewer wrote about the slow response time.  However, I believe this is a plumbing problem.  The hot water flows out of the water heater almost instantly.  Sure, if you have a long run, there is inherently a delay in getting hot water---however, you would have about the same delay (within a few seconds or so) with a tank-based heater at the same location.  Our house is about 5000 sq ft.  We have multiple faucets turned on at one time and have never had a hot water flow limitation.  The water heater only turns on the flame when hot water is demanded (think about it--you do not pay to continually heat up a tank when no one is using the water heater) and the size of the flame is regulated by the tankless water heater to match the hot water flow rate (no large gas flow for a corresponding small hot water flow).  All of this means that the tankless water heater is incredibly cheap to operate.  We would have needed two tank-based water heaters anyway if we had not installed the tankless water heaters, and we have more than made up for the initial cost difference in the past three years.  The next 17 years (the expected lifetime of a tankless water heater versus 10 years for a tank-based water heater) is gravy.

Rinnai Tankless Water Heater Model 2532

# Interior wall mount with a single wall or roof direct vent. NO footprint. # Propane or natural gas # Direct vent; forced combustion # Up to 8.5 gallons per minute # Output: 15,000-180,000 per hour. # Digital control with preset temperature range from 96° to 180° # 87% efficiency # 23 5/8" height, 13 25/32" width, 8 13/16" depth # 5 year warranty # Self-diagnostic system—displays a code for the plumber # Typical life expectancy is 15 to 20 years

Additional Features
Volume Capacity
Power SourceNatural Gas
Energy Factor.82
First Hour Rating
Minimum Flow to Activate.5 GPM
Input15000 - 180,000 BTU/H
Water Flow Rate (GPM @ 75 deg. max)
Water Flow Rate (GPM @ 45 deg. max)
Release Date
Model Name/TypeMPNEAN/UPC
Green Options › Eco Friendly Green Products › Eco Friendly Home › Appliances › Water Heaters › Demand/Tankless Water Heaters › Rinnai Tankless Water Heater Model 2532