should be rusty stain or water drop visible underneath the nozzle of temperature sensing
pipe. If yes, repairman may judge it as the water leakage of temperature sensing pipe, so the
heating pipe shall be replaced.
4.
Water leakage of safety valve falls into two types: one is dropping water of pressure relief
opening during the overheating process of water heater, but this is a normal phenomenon. For this
reason, repairman may explain that this is a pressure relief functions especially designed for
protection of inner compartment; if dropping water causes any damage to the use, it is suggested
to solve this problem thoroughly by additional installation of pressure reducer.
(III) Fault analysis and troubleshooting for temperature limiter
Failure of temperature limiter is mainly attributed to abnormal disconnection of temperature limiter.
Typically, the machine is not electric, but the power supply is normal. For common hydraulic
expansion typed temperature controller, its temperature sensing part is located inside the heating pipe,
so the boiled heating pipe is prone to activation of temperature limiter.
Except boiling, temperature limiter is generally activated due to internal or external reasons.
Oversized contact resistance (Generally abnormal
figure is more than 50m Ω) among
sheet metals or
connecting terminals of temperature limiter results in electric overheating and thus activate
temperature limiter.
Additionally, drifting temperature point of temperature controller results in excessive temperature that
is close to or greater than the operating temperature of temperature limiter, which activates the
temperature limiter. In addition, if the relative key is damaged, leading to the continuous circulation
and regulation state, heating pipe is always working. In such a case, the temperature limiter is also
easily activated.
Another reason for action of temperature limiter is misoperation of an user who fails to feed water or
turn on water heater in feeding the water, so the boiled heating pipe trigger the action of temperature
limiter before temperature controller.
At last, maybe temperature pipe contacts heating pipe or these two pipes are connected upon being
covered by water scale. In such a case, heat of heating pipe is directly transmitted to temperature
sensing probe of temperature limiter, thus resulting in faulty action. Actually, the water temperature is
not high adequately. Therefore, it needs to replace the heater.
In case of the action of temperature limiter, repairman shall first check whether the temperature
controller is normal; otherwise, replacement of temperature limiter often cannot solve the problem
thoroughly, because problems of temperature limiter mainly result from temperature controller. When
the temperature controller fails to precisely control temperature, the temperature limiter will be
