Hot water mixing valve addition

Another Ranger tug owner who was at the SW Fl tug rendezvous in Jan gave me this idea and I finally got around to completing it. This is a Moen model 104465 mixing valve, it mixes the cold and hot water to a preset temp so you don't have scalding hot water coming out of the faucets. By removing the orange cap the temp can be adjusted, this was preset at 120 degrees. The 3 large brass fittings that are screwed onto the body are included with the valve. I found the hose barbed fittings that screw into them at Lowe's. The bottom fitting is a Pex as I couldn't find a 90 degree hose barb locally. A straight barb would also work but for my application I preferred the 90 as I also plumbed this into the cockpit Whale shower.
Use brass fittings, they sell plastic ones but they will leak.
I paid $40.80 for the valve on EBay and about another $25.00 for various fittings, clamps and a few feet of hose at Lowe's. The install is fairly easy and takes about an hour.

We have a similar thermostatically controlled mixing valve on Serendipity. It's one of the best additions you can make because it eliminates the temperature difference between the shore powered heating element and the much higher temps from the engine coolant heat exchanger. The shower handle can now be in the same position on shore power or at anchor without scalding anyone after running the boat all day.

Two other benefits --it allows you to keep hotter water on the tank, which eliminates chance of contracting legionaries or getting a musty smell. It also effectively increases the size of the tank. Great to do at home too!

I had considered this. However RangerTug has 3 factory installed mixing valves: 2 in the head and 1 in the galley. Not an issue and no savings installing a central mixing valve.

I'm not sure the factory mixing valves are thermostatically controlled. The way to check would be to see if the temperature at the faucet is the same on shore power as it is after running the engine for an hour or more (with the faucet handle in the same posiition).

You are correct, they are not thermostatically controlled. I purchased a thermostatically controlled for our Nordic Tug as it had no single manual mixing valves - separate valves at each sink for hot and cold. Sold the boat before installing. I may go ahead and install in our R31 as an extra safety precaution.