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Marc, Plumber
Category: Plumbing
Satisfied Customers: 1126
Experience:  Plumbing heating & home maintenance contractor
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My mixing valve is behaving incorrectly It runs the shower

Customer Question

My mixing valve is behaving incorrectlyIt runs the shower good and hot but can't stay hot enough to run a full tubIt did up until about a month ago--a full really hot tub of water. Now moderately warmIt will throw out full hot water on the tub setting for a few seconds then revert to warmI have an instahot inline electric water heater and a smart electric meter.I dont know how these may interactThis equipment is four months oldThoughts?
Submitted: 8 months ago.
Category: Plumbing
Expert:  Rick replied 8 months ago.

Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.

I'd be looking into the water heater not the tub/shower mixer. It sounds like the heater can keep up with the much lower flow for a shower but not the higher flow rate from filling the tub. If you can give me the brand and model number of the water heater I might have more insight into the problem.

Customer: replied 8 months ago.
Hi Rick thank youI'll look that up and get back to you.Here's the thing--it did great for about 3 months but has behaved that way the last monthIt's an in line electric tankless heater InstaHot
Expert:  Rick replied 8 months ago.

Get back to me when you have the unit's info