Rinnai EX38CTN Space Heater Wall Furnace, Direct Vent, Natural Gas (38.4K BTU)

I did not want to rely on the electric heat pump on the ductless system that came with my tiny house since I live in an area where winter temps are below zero on a regular basis. I was familiar with Rinnai products since I had previously purchased a Rinnai gas water heater. This product was the perfect size and since the house is a total of 400 square feet, the specs claimed that it would heat the entire space. I installed it myself but the installation instructions that came with the product were not great. In searching the internet I found a YouTube video that clearly demonstrated how to install. I watched that a couple of times and without that video I would have been lost and would never have been able to self install. With the video the installation was very easy and straight forward. It took me less then one hour to install and get it running. My tiny house was delivered in January and the temps were in the teens and less every day. The first thing I did was to install the Rinnai wall heater. Once installed I turned it on and set it to 68 and left it for several hours. The outside temp was 10. When I came back a few hours later the interior temp throughout the entire tiny house was 68. It is now the end of February and it has been on and heating for over a month and it has been perfect. I am totally confused when I read reviews that complain about the noise. My unit is almost completely silent at all times and performs perfectly even when the outside temps dropped to 18 below zero. The heat is pretty much even throughout the house even in the bedroom which is in the back. My house has an upstairs loft and that is warm also which is not surprising since the heat naturally rises. This is the perfect heating unit for tiny houses like mine and so far (fingers crossed) I can not find anything about this product that I do not like.

I bought this furnace in Fall 2022 to replace an old wall furnace and it has performed very well throughout the cold winter, keeping the heat constant within about 2 degrees in my large bedroom. The bedroom is not heated by the main house furnace and is about 350 sq ft. It is very easy to install and use, no special wiring as it plugs into a standard wall outlet. I only needed to run some gas piping from my main line in the house to the heater. I like that it blows warm air at floor level keeping the whole room comfortable. The display is easy to see and use. I only set it to the heat I want locally on the unit and it does the rest. There are some other functions but I have not had a reason to use them. This furnace is designed and built very well as I expected from a Japanese manufacturer. I did not install a separate thermostat but that is an option. The only thing I do not like about it is the noise it makes each time the heat cycle starts. There is an igniter that clicks pretty loud followed by a short buzz when starting the heat cycle each time. I have come to ignore it and have no trouble sleeping, but my wife has complained several times about it. I'm hoping it lasts a long time for the price.

Fantastic Japanese engineering design and build quality. Pretty easy to install, quiet during operation, and the multi-stage / variable gas valve + burner throttles in 6 or 7 steps between 5,500 and 11,000 BTU, which helps the unit to "home in" on the correct level of steady-state heat output to keep the space at a constant temperature. Also, the online vendor I bought from, efaucets, did a fine job with packing & shipping. The (6) individual units all arrived on a single pallet via truckfreight. I've installed 3 so far and all are working perfectly.

Great unit works at least as well as expected. Fast shipping...would buy again.

First off these units have made us Rinnai fans and we recommend the brand to anyone and everyone. We had a previous model but the fan bearings seized in up after 16 years. We have 2 issues: 1. The product was delivered damaged. i did not receive feedback from the company, at least not that i am aware of when i tried to make contact. the mounting brackets were bent pretty bad but were fixable; however, the bottom left side (when looking at it)of the unit was bashed in as well. that is not fixable without taking off every painted piece you can see to get to the units frame. Since it is on the bottom back corner of the unit it is virtually invisible the way we have it installed. Probably would have sent it back but our previous model died in early February in eastern Oregon. we were sort of over a barrel, so we kept it. 2. The other issue with the unit is that it must have different sensors than our previous model. We have a 135+ year old house the winter chill just seeps in. Our old model ran more more or less continuously, quietly humming in the background, going from low to medium. This new unit gets the house to temp fast, then turns off....then 5-10 minutes later fires up and heats the house, then turns off... We aren't sure if it is actually louder than the previous model or not, but it is definitely noticeable since it cycles from off to medium/high. After 1 month of use the gas bill seems the same as always. Lastly, and this is not a complaint, Rinnai did away with the metal hatch cover over the buttons. We prefer the look over the old cover. Downside: the cat likes them, too. He will sit on that end, which is near us, and look out the window, occasionally getting by the "child lock" and turning the unit off. So far he has only turned it off once while we were asleep.

I bought this to replace a 22,000 btu Rinnai wall heater. So far it has been relatively easy to install and puts out considerably more heat. Winter will tell. The vent pipe was the same as the smaller version and in the right location helping with the install. The old heater will be installed in a room where it is difficult to heat

Good Quality, highly recommend!

The heater arrived on time and the package was in great shape. I did my own install and this unit works great! Very easy to install. I heat my 800 sq. ft. home in Michigan using this and it keeps it nice and warm!