You can fix this
Likely cause: the water heater, not the shower
If the sinks are cold too, the shower valve is not the problem. Start with the water heater.
Why this happens
Moen's first possibility for a shower that will not get hot is that hot water is not being supplied to the valve at all. When every tap in the house is short of hot water, the source is the water heater or its supply. A. O. Smith lists insufficient hot water supply among the signs a heater needs repair or replacement.
How to fix it
- If you smell gas near the water heater, leave the house now and call 911 and your gas utility from outside. Do not flip switches.
- Otherwise, check the water heater's fuel type and age on its data plate.
- Follow the water heater troubleshooter linked below.
If this does not fix it, tell the plumber
- Every tap in the house is short of hot water, not just the shower.
- The water heater's fuel type, make and age from the data plate.
- When it started.
Build the full list: what to tell the plumber.
Start this troubleshooter over
References (every fact above comes from one of these pages)
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