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Glow Brand · Boiler troubleshooting

Display normal but hot water not hot enough

C95 & C140C95 & C140 Combi

What is going on

Glow Brand C95/C140 shows normal on the display but the hot water is not hot enough. Usually it's a setpoint thing or the mixing valve. Scald risk is real above 120 F, so don't just crank it up.

Likely causes

  • DHW setpoint set too low for the type of tank
  • Thermostatic mixing valve set low or not working correctly

Check in this order

  1. Raise the DHW setpoint about 120 F with no tank, 120 to 140 F with a sensor tank (mode 1), 120 to 130 F with an aquastat tank (mode 2).
  2. Check the thermostatic mixing valve. Any setting over 120 F needs one installed.
  3. Confirm which mode the boiler is set for before changing the setpoint.
  4. Check delivered temperature at the tap with a thermometer, not by hand.
  5. Explain the scald risk to the homeowner after any increase.

Applies to: C95, C140 (NG and LP)

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Source: Glow Brand C95 & C140 Installation & Operation Manual V.01282025 , Sec. 13.2 p.74. Written in our own words; check the manual for your exact model.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.