V-Models

I've waited nearly 2 months before I wrote a review. Here's my summary: 1. The installation is easy if you are replacing an existing unit, I replaced dual tank water heaters and relocated the tankless heater closer to the majority of the water users in the house so the installation was more time consuming and difficult. The instruction manual is awesome, take the time and read thru it (prior to buying) and follow it strictly. I bought a gas fired unit, had the gas company come out and validate the inlet pressure and ran all the calculations recommended. Installation took 4 days since I had to run additional gas piping, extend hot and cold water lines and install the vent piping to the exterior. 2. After you've read the manual, plan your installation carefully (vent, water in, water out, gas piping in, power). These all converge around the unit which isn't large and will take planning to make it fit and functional. Purchase all the vent pipe ($$$), water piping, gas piping, and valves for the unit (the bundle of all of these are not inexpensive) 3. The unit fired up after the second try (it had to vent the air out of the gas line on the first attempt). The start up was very easy. 4. My wife likes HOT water, the unit is delivered with a maximum of 120 degree output. I queried the internet and found the program button sequence to get it to 140 degrees. It worked instantly, but after an hour the unit reset back to 120 degrees and the process wouldn't let me place it back to 140 degrees. I called the service desk and gave my number for a call back. 30 minutes later, the call came in. The service tech asked a few questions so she knew which unit I had purchased and then I communicated to her what I had experienced. She told me that the code I had used was for a different unit and she directed me step by step how to program the unit. (I had the panel open and performed as she told me each step). It took 30 seconds and the unit has worked correctly ever since. 5. The closer the unit is to the usage point the faster the water heats up, so don't have expectations that you'll get instantaneous hot water when there is 20+ feet of cold water in the pipe that has to be pushed out by the hot water, but it does heat the water extremely fast and it's on the way as soon as you open the hot water faucet!

The piping that, in my case went up through the crawl space, then through the roof was tricky to install. Ordered all new pipe after measuring carefully and cataloging the fittings I'd need (45's, 90's, and so on). Make sure to order the right diameter double-walled pipe. Look online. I ordered online and the company actually shipped the same day, and it came the next, which is nice if, like me, you are without hot water in the interim. S. Brewer's review is excellent. He covers all the crucial points very well. He explains clearly what you will be faced with if you decide to DIY the job. It was challenging. When you get to the point of lifting the unit up to hang it on the wall while simultaneously marrying it to the vent pipe, a second set of hands would be a major plus. I did it myself, but a second set of hands would be real boon at that point. I was able to use the existing hole in the roof, but, as it turned out, the contractor who built the house preferred to cut a gigundo hole in the roof instead of doing the geometry to accurately predict the penetration location and hole size. To compensate, I created a plywood insert with a proper hole cut into it, pre-drilled the screw holes, and then used light cord to pull the "mask" up from above, up on the roof. Once I had it placed properly, I used a right-angle drill to drive in the screws from underneath. Don't forget that you'll need a flashing unit on the roof to make a good waterproof seal, and also some roofing tar to further seal it. Be careful when lifting the shingles to slip the flashing unit under them to avoid breaking them. If you do some minor damage to the surrounding shingles, use the roofing tar to compensate. Once installed, the unit works very nicely with the caveat that it does not seem possible to set the temperature above 120°F. That's really sufficient, but my old unit was set at 125°F. Not a deal breaker. If you've not had an on-demand heater before, be aware that when running hot water, there's a lag before you actually get hot water. With this unit about 20' from the kitchen sink, that's about 30-45 seconds before the water warms up. Overall, very happy to have hot water again, and this unit outperforms the previous, larger capacity unit it replaced. Install a phosphor filter upstream from the unit to reduce maintenance flushing. Do install the valve set that will later permit de-scaling the boiler tank. This is important for the longevity of the installation. TIP: use the woven steel, flexible pipes to connect the unit to gas, inlet, and outlet pipes. These are much easier to work with than their copper counterparts, which are hard to bend-- MUCH easier. Good luck. If you prepare well ahead of actually doing the job, you will greatly reduce the stress factor in carrying out the actual installation. Do your homework. YouTube is your friend. ... and DO read S. Brewer's excellently written and potentially very helpful exposition on the entire process of installing these units. p.s. If you need hot water in a hurry at your taps, you'll want to spend the extra spondoolix for the unit with a recirculating pump: it's a luxury, but if you prefer faster delivery of hot water to your taps, you'll want that version of the heater. Cheers, N.

Installed this in November 2018. Been hassle free, working perfectly since then. Love the endless hot water, and being able to refill the hot tub with hot water is great. We have extra hard water, so I flush it with 3 gallons of pure food grade vinegar every 6 months. This is critical, but also really easy, once you set up isolation valves and get a good little pump and a 5 gallon bucket. I flush with the heat on, set to lowest temp, only takes 20 min to run clear. New instructions say to run it cold with heat off, last unit we had in 2001 said to let it heat the vinegar for faster cleaning. Not an easy DIY install, especially the gas line upgrade. I had to run 60ft of 1 inch gas line at the last house, was a difficult job. Many cities don't allow homeowner gas line work, I got lucky and was able to get permits in 2 cities over the years. Vent kit install was fairly easy, out a side wall, cut a big hole in the wood rim joist. Needed to drill and saws all through 6 inches of wood, took a while, but pretty basic. You need to do a lot of planning and make sure your vent is not too close to a window. Check with your city first to learn their requirements, they can vary a bit. Lots of plumbing had to be moved/replaced, as we moved the location about 8 ft away from the old one. Even with all the work, the payoff is worth it. Endless hot water, lower gas bill, and about an extra closet of floor space gained. That was huge in a small living space.

We installed this on a shipping container Tiny Home. The pipe fittings were tight and well made. The installation confusion centers around the electrical connections. First, the rubber grommet where the power wires exits the unit obviously does not meet code fo an external application and the grey plastic fitting does not match any PVC thread size. Secondly, the wires themselves are only 20 gauge. These do not seem to meet any code out there however after much searching of the internet, it seems that even professional electricians just wire up to it. We connected 12 gauge wire with wire nuts inside the cabinet and called it a day. The electric connections are supposedly only used for the LED display and the spark that lights the flame so we assume that gauge internal wire is ok. As for the PVC connection, we saw varied approaches to try for a water tight connection and we came up with using a 1/2" Schedule 40 female threaded connector pvc glued into their plastic connector. This connects to Liquidtite connectors and from there using those connectors and pipe into the container. This is the best water tight installation we could come up with that meets code. Lastly, it functions perfectly and within 30 seconds the water is quite warm and within a minute quite hot. All in all a very good purchase and other than the electrical connection very easy to install. We would certainly recommend it to anyone considering a tankless heater.

This water heater was easy to install and works great. It is energy efficient. Love that we could install it outside and not take up space in the house. And love having hot water on demand quickly and not running out of hot water after a few minutes.

3.5 years after purchasing I love this product. Easy to install for a VERY handy homeowner. water is instantly hot and easy to control temp. I can run the shower and washer at the same time. I can fill my tub and never run out of hot. It's quiet and efficient. I am happy with this product and writing this review without incentive because it's actually a good tankless water heater

Second Rinnai unit that's experienced frozen coils when the temperature dipped to 10 F. That's despite building a housing for the unit to protect from wind, wrapping the unit with protective insulation and using electrical heat tape around the pipes and the unit itself. Worked well during warmed weather, but I can't recommend for freezing temperatures.

Our 12 year old Takagi Tankless DIED the first night of “Winter Storm URI” here in Houston. Curiously, it did not freeze, but apparently the controller board died and we could not get natural gas ignition. Ordered a Rinnai V75en the next day (Tuesday) and it arrived the following Monday (a day earlier than the revised Promise Date). From delivery to Hot Water was under three hours, including standing in line at plumbing supply place to get a longer natural gas yellow metal hose. Pros: INCREDIBLY easy installation. Just make sure you buy a diverter valve kit; I bought a new kit rather than reuse the old valves, but not really necessary. However, you should NOT reuse the yellow metal gas hose, as it has metal-to-metal seals which shouldn’t be reused.. VERY good quality. Lots of Japanese brands are now made in China, but these are still Japanese-made. GOOD quantity of hot water. Multiple users (e.g. shower, washing machine, dishwashing) is a cinch. PRICE is pretty reasonable; tankless heaters seem to last about 10 years with zero maintenance, much longer if you follow the back-flush recommendations to the letter The ONLY Con: If you use the included controller (interior mount only) you can get temperature control in 5 degree increments from the default 120 deg F to 140 deg F. If you DON’T use the controller , you can set a dip-switch for EITHER 120 -or- 140 degrees F, nothing in between. We are not set-up to use an interior controller (which would require major surgery) so we can either buy a weatherproof exterior box for the controller, or use the dip switches. You can not set the temp with the controller, then remove it, as without the controller installed the water temp reverts to the dip-switch settings. We’ve left the water temp at 120 deg F, which is a lot safer for the tiny grandkids, and we’ve squirreled-away the controller to use for diagnostics if later required. Not a deal-breaker, but sure would be nice to set temp with dip switches, then have a PLUG on the side of the unit for controller to use for diagnostics without removing the front cover... Time will tell if the Rinnai is durable, but the ease of installation was super important under the current circumstances; after this Big Freeze, plumbers are changing $100 just to GET ON THEIR LIST. Meanwhile, we took our first hot showers ina week only a couple of hours after the package appeared on the doorstep.