DURAWATT
®
ELECTRIC WATER HEATERS
PV500-6 05/13
13
7 MAINTENANCE
A preventative maintenance program is required to ensure a long trouble-free life of the water heater.
Maintenance Schedule
COMPONENT
OPERATION
INTERVAL
REQUIRED
Tank
Sediment Removal Every 3 Months
Flushing
Relief Valve
Inspect
Every 6 Months
Test
Electrical Connections
Inspect
Monthly
Inspect for wire discoloration
Electric Elements
Check
Every 6 Months
Amp Draw
Electric Elements
Remove & Clean
See Page 9
7.1 Flushing
1. Turn off the heater electrical disconnect switch.
2. Open the drain valve and allow water to flow until it runs clean.
3. Close the drain valve when finished flushing.
4. Turn on the heater electrical disconnect switch.
7.2 Draining the Tank
The heater must be drained if it is to be shut down and exposed to freezing temperature. Maintenance and service
procedures may also require draining the heater.
1. Turn off the heater electrical disconnect switch.
2. Close the cold water inlet and hot water outlet valve to heater.
3. Open a relief valve to vent the tank pressure.
4. Open the heater drain valve.
5. If the heater is being drained for an extended shutdown, it is suggested the drain valve be left open during this
period.
7.3 Sediment / Lime Scale Removal
Waterborne impurities consist of the particles of soil and sand which settle out and form a layer of sediment on the
bottom of the tank and adhere to heat exchange surfaces. The amount of calcium carbonate (lime) released from
water is in direct proportion to water temperature and usage. The higher the water temperature or water usage, the
more lime deposits are dropped out of the water. Lime accumulation not only reduces the life of the equipment but
also reduces efficiency of the heater.
7.4 Temperature and Pressure Relief Valve
The relief valve should be checked at regular intervals by manually opening the valve. The openings inside the
valve may become restricted by a buildup of scale and become inoperative. If the valve does not open and close
properly and does not blow off internal pressure when tested, it must be replaced. Shut down heater, relieve internal
pressure and replace relief valve with a like kind or one meeting the requirements stated on the rating decal located
adjacent to the relief valve mounting location.
7.5 Low Water Cutoff
The standard low water control is electronic. Inspection should be made of the electrode on water heaters equipped
with electronic low water devices.
