Can anyone please help me identify replacement mixing valve?

galaxydog

I have a cast iron hydronic radiant floor heating system built about 25 years ago. After speaking with two different heating techs, I believe my mixing valve needs to be replaced. I don't have the $2k+ to spare for the job, so I am looking at changing it out myself. I was told it's a 1 1/4 " size. I don't see mixing valves that look like mine online though. Where mine (no labeling) is large and extends in the x, y, and z axis, these one's online seem compact and extend in the x and y axis. Can anyone please help me understand what part I need to replace it with.

hot_rod

Heatway sold that valve as the AllTemp 2. It had an orange label on top. I'm not remembering the manufacturer. The smaller mix valves they offered were Hoffman.

The is somewhat similar to the Watts 170, perhaps an earlier version.

If it still controls? the o rings could be replaced. If the small heat motor "pill" inside is bad, you need to find an OEM part

hot_rod

I actually still have a cut away of that valve. Only 2 o-rings inside, both at the top nut and around the stem. The valve mechanism itself is brass on brass.

Looks like someone tried to scratch out the name Watts on the bottom cap 😲

galaxydog

Hello hot_rod,

I am sorry for the late reply. Life threw me a major curve ball.

Thank you so much for responding to my post. I really appreciate your time and efforts.

I haven't been able to find this exact part. I also have trouble finding a replacement part.

Could you please suggest anything that could work?

EdTheHeaterMan

This might work for you: https://www.supplyhouse.com/Caleffi-523178A-1-1-4-Sweat-High-Flow-Thermostatic-Mixing-Valve-7-6-CV-Lead-Free

there are less expensive mixing valves but they may not be adjustable to the temperature you need for Radiant floor heat. @hot_rod may have a better choice for you.

hot_rod

unfortunately I don’t know if any other with that connection orientation

I am almost certain that is a Watts N170 valve

It has been replaced with a LF model, lead free, and looks a bit different.

There were repair kits available for those legacy valves

A rebuild kit is a lot less $$. That is s pricey valve to replace with a like version

The Watts website shows part numbers and kits for discontinued products Find the repair kit # and check e bay a lot of old inventory ends up there.