I ordered a thermostatic mixing valve to deliver 76 degree water to my aquariums for water changes

[Pepere]

https://www.supplyhouse.com/Resideo-Braukmann-AM101-1LF-3-4-Female-NPT-Lead-Free-Mixing-Valve-70-145F

I have these on my water heaters to allow the tank to heat water to 140 degrees and this device mixes hot and cold to send 120 degree water through the pipes to avoid scald hazard.



I will plumb in the basement and have a tee fitted to the outlet fitted with a thermometer probe in a well to aid in calibrating, recalibrating temp as needed. There will be a spigot in the basement near those tanks and ann additional one upstairs that I can attach my python hose to.

Getting tired of having to go back and forth between tank and faucet to get temp allright….

This allows temperature adjustment between 70 - 140 degrees.

 

[Pepere]

Below is a view of one installed on a water heater and a Tee plumbed after it with a thermometer installed in an immersion well.


Below is an older one disassembled showing thermostatic spring valve seat and valve body and calibration adjuster to set the temp desired.

 

[BigWave]

We use a varient of these at work on all the bathroom faucets, maybe 50 total. Be aware they fail more often. Maybe 3 a month.

 

[Pepere]

Be aware they fail more often. Maybe 3 a month

When they fail, do you service them or replace them?

 

[BigWave]

Just replace. Have 10 or so on the shelf. Its for any number of things. Rust in the pipes clogging the mechnisims inside, spring failing, its cheaper in the long run to just toss bad parts and install new.
Edit: I just put the warning out there so your aware. Not to scare you away or anything. Just be cautious.

 

[Pepere]

I have 7 of these in operation. I have experienced maybe 3-4 of them sticking in the past 10 years.

Generally I bypass them with valves, shutting off the valves to the affected mixing valve, take off the adjustment knob, remove the adjusting mechanims and remove and clean, and use stainless steel pipe fitting brush to clean out the body and flush well and reinstall and see years of good service.

I do have a settling tank where the water enters the building for the heavier debris followed by a whole house pleated sediment filter.

With very soft water, I avoid hard water buildup.

But yes, anything mechanical with moving parts have failings…

 

[JacksonL]

As an ex-plumber who spent many years working with these. The number one thing that kills these valves is debris entering them. They do have simple mesh sieves on the inlets generally, but if you want a better chance at them lasting, install a simple pre-filter that can be cleaned easily.
They are designed to fail ‘cold’, so if you notice the temperature of the output dropping gradually, it’s time to pull them apart to flush before they die completely.

 

[JacksonL]

They are like most residential plumbing valves, a complete lottery.
Some will last forever despite the roughest treatment and some will conk out in a few years despite the best treatment.