Aquanta turns your hot water heater into a smart hot water heater

[larryllix]

2 hours ago, Jojo-Madman said:

I have a better understanding now why Aquanta field trial result savings were also so dismal for NG water heaters.

In talking with WH manufacturers, I have found out that a natural gas 50G "power-vent" water heater which most utilize flue dampers and heat traps, and have approx 2" of foam insulation will take 96hrs under test conditions to react room temperature. My understanding of the testing conditions are that the room temperature is 70F and the water heater is at 140F. Given that 70F is within the normal room temperature, this energy isn't even really lost in colder climates such as mine, as it is only lost to into the living space.

This being the case, shutting off the burner control for 8~12 hrs a day via their smart controller as far as I can figure out is never going to yield a 10% savings for NG water heater. The idling conditions are not consuming much energy in order to do so.

I have simply rigged up a z-wave appliance plug to the 110v AC power cord for the controller and exhaust fan and it up so that I can shut it off when not home for long periods of time.

After a week of vacation with the tank shut down, have a shower when you get home and see how they keep their heat. Myself and a neighbour found a lukewarm shower but a full tank of water before it ran out. NG water heaters have a pilot flame that keeps them warm enough usually.

[larryllix]

On 9/20/2020 at 12:47 AM, tiwillti said:

Can anyone here give any recommendations on tankless water heaters? I'm considering buying one for my flat, but I'm not sure if it's really worth it. And also do you know if there are any smart heaters among tankless ones. 
P.S. Sorry if I chosen the wrong topic. 

No. I have installed three units of two different brands in my home in 11 years. If you have aggressive water, they do not last. Then there is the flushing and cleaning maintenance every year. Buy vinegar stocks. There is no money savings when you have to replace them that often.  Mine heats my house also so I have hard usage.

It takes some time to get yoost2  the "cold water sandwich". Get the smallest unit, not the largest. They have problems with very low flows so it may be difficult to wash your face without it going cold, due to not enough flow, or burning you, attempting to keep the hot flow high enough.

I can't recommend these units on NG. The Rheem units have a more sensitive minimal flow sensor than the Rhinnai units did.

[apostolakisl]

On 9/20/2020 at 9:15 AM, larryllix said:

No. I have installed three units of two different brands in my home in 11 years. If you have aggressive water, they do not last. Then there is the flushing and cleaning maintenance every year. Buy vinegar stocks. There is no money savings when you have to replace them that often.  Mine heats my house also so I have hard usage.

It takes some time to get yoost2  the "cold water sandwich". Get the smallest unit, not the largest. They have problems with very low flows so it may be difficult to wash your face without it going cold, due to not enough flow, or burning you, attempting to keep the hot flow high enough.

I can't recommend these units on NG. The Rheem units have a more sensitive minimal flow sensor than the Rhinnai units did.

Well this is a thread that probably has been spammed, but anyway, my experience with tankless is very different.  I have 2 of them, my in-laws have one in their current house and also had one in their old house.  They have a track-home type construction with the entire neighborhood having tankless.  I suspect your issues revolve around the fact that you are in Canada.  Here in Texas the water isn't that cold to start with so the cold water sandwich doesn't happen or if it does it is pretty subtle.  We have endless hot water.  The only downside is not being able to do recirculating so the water isn't always hot at the faucet.  We have it mounted into the wall so there is no wasted space for the tank.  Ours are 10 years old now and haven't had a single service issue.  I set it to 125 which required forcing it out of its default 120 max.  I forget the brand but can check when I get home.  They run on propane.  I haven't noticed any low-flow problems.  Now you can't just turn the faucet on to a trickle, that won't work, but turning faucets on at full flow to a comfortable temp for washing hands or dishes or whatever, it runs just fine.