Rinnai RU199iN Condensing Tankless Hot Water Heater, 11 GPM, Natural Gas, Indoor Installation

October 2023 - The takeaway is that anyone who complains about these not working well did not install it correctly (and won't admit it). I am shocked at how well this thing works. I am still amazed how quiet it is. No further occurrences of errors. Works fine with furnace running even supplied through a 1/2in tee from a 1 in main supply to the basement.Sep 2023 Brief update: I had one occurrence of error 12 - flame out. But it hasn't happened again. I hope it was a fluke caused by our gas supply and nothing else. If not, I'll investigate and update my review afterward.Original review Aug 2023: My recent experience with the Rinnai RU199iN tankless hot water heater has, in a single word, been excellent! It's like the ninja of water heaters - quiet and incredibly efficient in performance.Getting it up and running was straightforward, similar to the typical expectations of setting up the necessary plumbing, gas, venting, and electrical work. However, it's important to note that this isn't like replacing a conventional tank where everything falls into place easily. Rather, it is like a fitting jigsaw puzzle into place, not easy per se, but not too daunting either. The most fun was renting a rotary hammer from Home Depot to bore the vent holes though brick.For anyone worried about gas lines like me, you may appreciate this little surprise. The unit appears to have an internal gas booster pump. Ingenious, right? I chose to run it off of an existing gas line which was originally fed from a 1-inch line from the meter, with a brief downgrade to a 1/2 inch, before returning to a 3/4 inch. Despite my initial concern, it seems to function flawlessly under these conditions. But I am not complacent, and plan to eventually test all my gas appliances together in full throttle, just to be certain that the supply line capacity holds up.One of the most commendable features of the Rinnai RU199iN? Stable hot water output. Not once did I experience any hot water fluctuations during use. An absolute win! However, I did notice a slightly longer delay to get hot water on a cold startup, taking approximately 10 to 15 seconds longer compared to traditional heaters. But once it gets going, it provides steady, continuous hot water supply.Oh, and I must add - I did the installation myself. So, for all the DIY enthusiasts out there, this little project is quite manageable and rewarding.In conclusion, the Rinnai RU199iN tankless hot water heater has proven to be a stellar addition to my home. It delivers consistent performance, minimal noise, and solid dependability. If what you're after is a top-notch appliance that couples functionality with ease of use, then the Rinnai RU199iN certainly fits the bill. Five stars for this one, without a second thought!

First tankless with new build. Very happy after six months. Tankless is definitely the way to go. Plenty of continuous hot water and lower natural gas bill. Takes up less space in garage. Rinnai appears to be high quality. Friends recommended and say the same, trouble free. Highly recommend.

We bought and installed a Rinnai RU199iN in 2019 and as of today we could not be happier with it.In my initial review I mentioned that the water pump is audible, but this turned out to be negligible, and in our case, mostly due to the installation location of the unit. We really have no complaints after six years of use. Below are a couple of reasons why we love the water heater:- The water gets hot very quicky, the unit turns on the moment water flow is detected- Two people can shower with ease there is enough hot water (and this is in an old house with partially some 70-year-old galvanized plumbing- Endless stream of warm water (well that is the point of a tankless water heater I guess)- Very low maintenance: We live in SoCal and have the unit in a closed and unheated cabinet outside. I installed a warming lamp that kicks in when the temperature is below 40°F. The only maintenance is to change the in-line water filter once every year. The recommendation is for 6 months, but since we only are the two of us, replacing the filter annually seems enough.

We purchased this tankless water heater in 2020 after going through 3 traditional water heaters in 9 years. This tankless water heater has been amazing for our family of 8. 4 years in it is still going strong. We no longer run out of hot water while trying to get the whole family through showers and baths. The output is plenty for almost everything with a few caveats. The first is we can run two showers simultaneously without any noticeable decrease in water pressure but when running all three there is a significant drop in water pressure but additional units can be chained together to solve that problem. The second issue we've had is with our front-load washing machine. I'm not sure if it's just our model but for whatever reason if we run two showers with the washing machine you can tell every time the washing machine starts pulling water. The dishwasher and sinks don't have any noticeable impact to water flow. So if you want to run more than two showers at a time you may want a second water heater but for our family of 8 this product has been amazing!

It works absolutely great. Installed and running with a little work after replacing a tanked type water heater. I have 1/2” propane line and it calls for 3/4” but still works great even with two showers running at the same time.

I thought I was going to be disappointed in the size for volume because the website has a configuration model that stated the next size up for my house size. I am not disappointed. The install is pretty easy if you know how to plumb, or have an idea of how you want to plumb this in yourself. It sets at 120 F without needing to make a bunch of adjustments to get it up and running. You could set it up on cinder blocks and hook hoses up to it and have hot water.I have had the washer going and take a shower with the kids flushing the toilet and washing their hands and not lost the hot water with a minimal pressure drop. I did have to place a 2 1/2 gal bucket underneath for the excess that drops out of the bottom, but I only empty that once in the five months I've had it running. This is a whole house unit that operates as intended with no hiccups to speak of. We have had power outages and not had to reset anything. It's just there and we don't have to think about it.I would recommend sending water to it through a filter system regardless of where you live.