I’m hoping among the many at GBA with deep expertise, someone knows more about thermostatic mixing valves than anyone I’ve been able to contact at Pfister.

 

I have learned that, for a shower, where scald protection is now required per the IRC, a thermostatic mixing valve is superior to a mere pressure-balancing valve.  Non-digital thermostatic mixing valves have one of three kinds of sensing elements, liquid-filled bellows, wax, or bimetal, with significant differences in performance and longevity.  The two most affordable thermostatic valves I’ve found are the SentinelPro Thermostatic Pressure Balanced Shower Valve by Speakman and the 1/2 in. Thermostatic Temperature and Volume Control Tub and Shower Valve and Cartridge by Pfister.  Speakman tells me their valve uses a wax-based sensing element.  After multiple emails and calls, including an “escalation,” Pfister tells me they can’t find that information.  I would just buy the Speakman, but its warranty is five years whereas Pfister’s is lifetime.  If Pfister is using the same or better technology, their valve would be preferable, as the prices are similar.

 

Here are links to the valves and to a PowerPoint about the types, etc.:

 

 

 

 

Do you know which type of sensing element the Pfister valve uses?