Noritz · Water Heater error code
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Guide · Water HeaterPower-vent tanks add a 120 V blower, an air pressure switch and often a vent temperature limit. Most no-heat calls are electrical supply, a kinked or water-filled pressure switch tube, condensate in the blower, or a restricted vent. The tech checks power and the low-voltage safety chain and inspects visually; gas valve, burner, igniter/flame sensor and vent repairs are referred to a licensed gas technician.
Guide · Water HeaterA heat pump water heater pulls heat from the air around it, so the location matters more than with a plain tank. Check four things before the sale: enough air volume (or a louvered door or ducting where the maker allows it), a space that stays within the operating temperature range, a place for the condensate to drain (floor drain, sloped line or condensate pump), and a dedicated 208/240 V circuit sized for the model. Add the usual tank items: pan where required, T&P discharge, expansion tank on closed systems, and a permit where required. The refrigerant circuit is factory sealed: any sealed-system diagnosis or repair is BLOCKED (EPA 608). Replacing a gas unit also means a licensed gas tech must cap the gas line and deal with the old vent.
Guide · Water HeaterMany tankless complaints are water-side: flow below the activation threshold, a clogged inlet screen, low-flow aerators, or scale in the heat exchanger. Gas supply, venting and combustion codes are blocked: diagnose and refer. Read the code first, then work the water side.
Noritz · Water Heater
05
Service due warning
Noritz · Water Heater
10
Combustion / exhaust problem
Noritz · Water Heater
11
Ignition failure
Noritz · Water Heater
12
Flame loss / weak flame
Noritz · Water Heater
14
Thermal fuse tripped (heat exchanger overheat)
Noritz · Water Heater
16
Outlet temperature spike (often scale)