Bests & Worsts Reviews from Amazon

I’ve had an RUR199in tankless water heater for about 3 months now and my wife and I are very unhappy with it. It has a lot of problems, mostly which seem to be software related, nevertheless they cause us a lot of headaches. We use this tankless water heater together with the Rinnai Control-R module, no wireless sensors. Here are the problems: 1. If the power goes out it reverts back to a temperature setting of 108, regardless of what the temperature was set to before the power outage. This results in luke warm showers for my family until someone complains to me. 2. If our internet goes out for an extended period of time the Control-R will not reconnect to the internet, and the water heater disables recirculation and reverts back to a temperature setting of 108. This results in long waits for hot water as well as luke warm showers. It stays like this until someone complains to me about it. It should maintain its temperature and recirc settings that it had prior to the Control-R disconnecting. 3. You can’t control the recirc settings, Economy or Comfort, using the Control-R app. This requires removing the unit’s cover and changing the settings. Why not give the end user control of this? The unit seems to be set to Economy mode so if we take a shower just before the next recirculation window we end up waiting a long time for hot water. Matter of fact you can’t even check which recirc mode you are in with the Rinnai app, this also requires removing the cover. 4. To work around problem #3 just mentioned, we try to use the Rinnai app to start recirculation on demand. The problem is, the app won’t let you, it says that recirculation is already enabled! But it’s not, so you end up waiting a long time for hot water. I think that Rinnai doesn’t let you start recirculation if enough time hasn’t passed since the last recirculation, it’s crazy though because you are forced to take a mostly cold shower or you waste the water while you wait for hot water, which defeats the energy savings of a tankless water heater. 5. Related to #3 and #4, sometimes after waiting a really long time for hot water, you finally get hot water, and then a few minutes later it cools off for no apparent reason, even when no one else is using hot water. Then you have to wait a few more minutes for the hot water to return. I don’t know what causes this, maybe recirculation is kicking on while showering which results in the unit getting mostly warm water, which is too small of a temperature differential for the unit to heat; I think this is similar to why tankless water heaters have a min flow rate, you need a minimum amount of gas flowing for proper combustion, not sure about this. Either way I don’t really care why. If this is a pitfall of tankless water heaters then they should let people know. If this is a recirc problem then Rinnai should consider a variable flow recirc pump and then choose the proper flow rate so that water can be heated to the set point at all times. 6. I use the Control-R to enable recirculation during the day, but keep it off at night after 11. If I take a shower well after 11, it takes a very long time to get hot water. It takes about 1 minute to get mostly warm water; this is how long it took my previous, tank, water heater to get hot water when recirculation was disabled, so this seems pretty normal so far. So, after 1 minute I get mostly warm water, but it takes a lot longer to get water that is as hot as the set point, 120 in my case. By a lot longer, I mean another 6 to 8 minutes, it’s crazy. I don’t know if this is due to the 3/4” pex pipes having to be heated, or if it actually takes the water heater that long to warm up to fully heat water. If it’s the latter then I would not recommend tankless to anyone. I’m not sure what the cause is here, but it seems unlikely it would be the pipes. Some of these problems might be Control-R specific, I don’t know and don’t really care, it’s a Rinnai system and should be reviewed together in my opinion, so I’ll post this same review for the Control-R. On a side note I haven’t spoke to my installer or Rinnai yet about these problems. I will definitely update this review when I do, if any of these issues are resolved. Also note that it is currently winter, but we’ve had these problems since day 1, which was back in the fall, so they don’t seem to be related to incoming water temperature (I’m in the south). Update 2 years later. All issues are same except #6. That was a plumbing issue. Water was traveling an unexpected direction through recirc pipes, hence the huge delay to hot. 2 check valves corrected that. Now I get hot water in a minute to minute and a half (from cold). There’s one new issue though. In summer, when the incoming cold water isn’t all that cold, if I lower the water’s temperature to anything less than the max, the water will go cold after a minute. The major issue is, it doesn’t go back to hot, ever. To correct I have to turn on a sink faucet so that the water gets hot and stays hot. So ridiculous. Called the plumber and they acknowledged these are typical problems worth these units, and that it’s normal. There are tankless water heaters on the market that don’t have observable min flow rates. They use a small buffer tank, but at least you don’t sacrifice comfort, and less of an energy penalty thank a huge tank. I’ll be trying that if I try tankless again.