179573 Bathroom Shower U by Moen Digital Shower Backup Battery Kit

If you have a U-Moen smart shower mixer, you NEED this! It will prevent you from giving the U by Moen 1 star. I'm not sure why it is, but when we would have a power outage (brief or long), the U-Moen wouldn't seem to cycle the valves, maybe its my slightly above national average water pressure. Because the unit comes back active with no errors, the control panel works and the Smart Phone App worked, but nothing would happen when you tried to start your shower. I'd have to shut off my supply valves, release the pressure, and power cycle the whole thing. It was so frustrating that I gave a low star and very displeased review of the U-Moen mixer. I got this unit (overpriced as it is for a plastic box and 6 D-Cell batteries), and now I couldn't be happier with my U-Moen!

After spending all that money on the U by Moen valve and controller, why would you skimp on the battery backup? Do it right the first time; it could be challenging to add later. This product is expensive but worth it! In my recent DIY Master Bath Remodel, we enlarged the shower so the spray heads would be far from the door. It would have been a far to reach a traditional valve, and I would have gotten wet just turning it on. U by Moen solved this problem by allowing me to put the control panel right inside the door, on the opposite side from the spray heads. I bought the 2-outlet valve for a shower head and three body sprays. Our shower is always the perfect temperature as soon as we step in (I like 101 degrees and my wife likes 109), and it maintains temperature even if someone is doing dishes, running the laundry or flushes a toilet.

This works great. Has batteries in a case that mounts in access panel and plugs into the u by Moen valve. If the power goes it automatically runs off this backup ..so you can finish your shower and get the shampoo out of your hair! If your powers out, your lights are gonna be off but I guess you could still shower by candlelight with this backup if you wanted/ needed to. Without this back-up the unit automatically just shuts the water off if your electricity goes out.

This is a God send. We had a short power outage and were still able to use our fancy new shower thanks to this. Keeps our Moen electronic shower working even when the power is out. A truly must have

This is a plastic box that holds 6 D-cell batteries, and feels cheaply made. It's bulky and hard to fit into the space. I used 2x6 studs for the wall, so it's better if you planned for the battery pack when installing the valve. It comes with 6 name-brand batteries, so about 1/4th of the cost is covered by not having to buy your own batteries. The batteries are in series to give a total of 9 volts, and D-cells will give you more amp hours (last longer) than a regular 9-volt battery (which is really 6 small 1.5v batteries in a package). The reason they say to use alkaline is rechargeable batters are around 1.25v which would only give you 7.5 volts. Where this came in handy: We had the U by Moen smart shower installed when we built our house. Due to COVID this took 18+ months, so by the time the valve was installed we were past the 1 year warranty. The shower worked fine for 6 months until we had our first power outage. After that, about once a month the shower would just shut down. I suspect the DC adapter is no longer putting out a consistent voltage. To get the shower working again it needs to be unplugged, wait 5 minutes, and plug it in again. I noticed it had a long wait time to reset while unplugged during the original install when we couldn't figure out why it wouldn't turn on.) The the wifi and preferences then need to be reset. Rant: I don't know why they didn't use non-volatile memory to store the settings and I consider this a design flaw. I have completely automated my house and not a single other wifi-enabled, Z-wave, or Zigbee device needs to be reprogrammed after losing power. I won't go into the other issues it has with home automation integration, but suffice to say the battery backup is needed if you want the functionality. Following the instructions for installing the battery pack, I plugged in the power first and then plugged in the battery pack. I immediately heard the values cycle and the saw controller lit. No 5-min wait. We haven't had it randomly shut down or have to reprogram the controller since. I took off half a star due to the price and construction of the battery backup, but it works as expected. As an electrical engineer I feel the system could have been designed better. Since I didn't buy the valve/controller on Amazon, consider the other 1/2 star for the system design.