Maintenance Instructions - A.O. Smith CAHP-120C Series User Manual

CAUTION: This water heater should be maintained by a qualified person. Failure to follow
these instructions can result in severe injury or property loss.
WARNING: Disconnect the power supply to the water heater before maintaining the water
heater.
6.1 General
1. The maintenance of the water heater includes cleaning the tank and cleaning up the scales
on the heating elements, especially in the area with harder water. It is recommended that the
tank to be cleaned every month. Check the scales on the inner surface of the tank and the
surface of the elements to determine whether cleaning is necessary, and the cleaning of
heating elements should be performed by local supplier. It is normal if there is a hissing
during the cleaning.
2. The temperature and pressure relief valve should be inspected every month to ensure it is
in effective operation. Pull the handle of the relief valve several times to ensure the valve can
switch freely. Please pull the handle of the relief valve once every month, and discharge 4~8L
water, which can prevent scaling inside of the relief valve.
3. The water heater is equipped with an anode to protect the enamel water tank from
corrosion through electrolysis. When the material of the anode is consumed completely, the
water tank would lose this protection. The anode should be checked once every year to
determine the consumption of the material or change the new one. When the anode diameter
is less than 1 cm, change it for a new one. Higher water temperature and softer water can
accelerate the consumption of the anode, so the anode should be checked more frequently.
Anode is a consumptive part and is charged for replacement as it is not covered by
guarantee.
4. The water heater is recommended to operate in the surrounding that is free from too much
dust.
CAUTION: When inspecting the T&P relief valve, the water outlet temperature of the valve
might be high and it could cause severe scalds, so be careful.
6.2 Cleaning the Water Heater
The drain valve of the water heater should be opened regularly to prevent precipitation
on the bottom of the tank.
1. Disconnect the power supply to the water heater.
2. Connect a soft tube at the drain valve outlet and put the other end to a floor drain. Turn the
handle of the drain valve to the left (anti-clockwise) to open the drain valve. Drain the water
completely. If there is no water flowing out after opening the drain valve, perform according to
the instruction of cleaning the precipitation.

6 Maintenance Instructions

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