Grundfos 99452459 (old part number 595916) UP15-10SU7P/LC Instant Hot Water Comfort Recirculation System 9H with NEW Digital Timer

Our kitchen sink is a long way from the water heater, so we either had to run the faucet for 2 minutes or boil a kettle whenever we wanted hot water. We live in Southern California so wasting precious water is not really an option. Now we get hot water in just a few seconds. The wife is happy, so I'm happy:-)The first decision was whether to chose an Under-the-Sink pump or an On-the Hot-Water-Tank pump. I chose the On-the-Hot-Water-Tank solution because the tank is in the garage, so any noise wouldn't be a problem, and it offered the opportunity to push the water to other sinks in my many branched system.I was concerned about a couple of things before I bought this unit:1. Would it work on my hot water tank with Heat Traps? Yes it does2. Would I have to remove the 'chimney' from my gas hot water tank to install? No I didn'tInstallation was a breeze. A couple of hours saw it done. I had an electrical outlet close to the tank in the garage, so that was no problem. Under the kitchen sink, the flex hoses from my faucet are not removeable and my hot and cold water come out of the wall next to each other on one side of the sink, not on each side of the sink as shown on the installation instructions. The flex hoses supplied are rather short, so I had to run those to the hot and cold inlets of the bypass valve instead of from the bypass valve to the faucets. To use the short hoses, I had to mount the bypass valve vertically, which a quick Google search told me was OK to do, and I can confirm that it works. All that is a bit confusing, so check out the photos and you will see what I mean.I didn't use the timer supplied with the unit. I bought a Kasa Smart Plug so I can run it from my phone. At the moment, we just run it for a couple of hours twice a day when hot water is usually needed. I can turn it on with my phone if we need it at any other time. The unit is very quiet, you have to get right up to it before you can hear it.We love this thing. Five stars no problem. Hot water in just a few seconds from the kitchen faucet where the bypass valve is installed, and a positive influence on most other faucets too. I will probably get another bypass valve for the Master Bathroom sometime in the near future,

This is looking to be another drought year so it was great not to have to waste water waiting for the warm!We had a plumber install it because it involved cutting the solid copper hot water line coming out of the heater - if one had flex line, it would be pretty easy to do oneself. The plumber said that most (?80%) of the retrofit recirculation pumps he installs use the existing cold water line for return (like this one) rather than a dedicated return line.The unit is absolutely silent. The only way to tell it is running is to feel the motor casing.The order comes with a pump unit with a long cord which plugs into a fairly generic timer. Rather than use the timer, we are trying a remote control switch (LoraTap Mini Remote Control Outlet Plug Adapter with Remote, 656ft Range Wireless Light Switch for Household Appliances). You hit the on button about 5-10 minutes before shower time. You just have to remember to hit the off button afterward.

Grundfos are a little more expensive than other recirculating pumps but they have a good rep among plumbers for reliability and are dead quiet so I got the new model for my new house and haven't regretted it. If your hot water line coming out of your water heater is flex/detachable (i.e. isn't a copper line that needs to be cut in to) then this is pretty easy for anyone to install whether you have plumbing experience or not. Otherwise a decent plumber should charge you $100-200 to install it depending on the going rate and whether they need to cut copper pipe for you.With a flex pipe it's as simple as, turn off water at the cold water inlet to the tank, open a hot water faucet downstream from the heater (bathtub works) to drain hot water out of the pipes - I've done two of these and never had to drain the entire heater with a hose like some install instructions recommend, but if you want now is as good as time as any to flush your water heater while you are at it - unscrew hot water outlet, install this in the middle with the inlet/outlet in the right direction, and you're done.The comfort valve installs at the furthest sink from the water heater and is dead simple to install, took me 10 minutes, 5 of which involved clearing out the area under the sink. Note that depending on your pipe setup and desired outcome you may want more than one comfort valve, which you can buy on Amazon for $49 - this kit comes with one.You'll get near-instant hot water now - it really does work. Slight drawback is your cold water will come out warm (not hot) at the faucet now as well, but it will go cold in 5-10 seconds, and my experience is that is way more preferable than waiting up to a minute (in my case) to get hot water instead, and a lot less wasted water too.This kit comes with a digital plug in timer, no longer built in to the unit - it looks just like the kind of timer you'd put Christmas lights on. It IS that kind of timer. Easy enough to set so you don't have to have the pump running all the time. I don't use it; I installed a Z-Wave outlet plug instead so I can control it remotely with my home automation system. That way at night, or when we are on vacation/out of the house, the pump shuts down along with the rest of the house.Overall these are worth it, very convenient, and will save you money and water, especially if you manage the power schedule. Finally, if for some reason your water heater is near where you can hear it, this pump is dead silent. It won't add to any noise level.

Very quiet and easy to install. I wish there was a way to adjust the temperature on the bypass valve as I would personally prefer the water in the line a little hotter. Still takes time to get full hot to make its way from the water heater, but it’s warm the whole time and WAY better than it was...and WAY less expensive than installing a return line.All in all, I think it’s a solid purchase.

Easy to install, works great. I was worried about it working on a newer hot water heater with heat traps from other reviews I had read but it does exactly what we wanted. It brings warm water to the sink immediately, not hot but warm. Very Quiet even my wife with super hearing doesn’t hear it! Can’t be happier.