Draining Water Heater; Filling Water Heater; Sediment And Limescale - andrews ECOflo Series Installation And Service Manual

6.8

Draining water heater

6.9

Filling water heater

6.10 Sediment and limescale

Issue 2 14/07/16
The water heater must be drained if it is to be shut down and
exposed to freezing temperatures. Maintenance and service
procedures may also require draining the water heater.
1. Turn off the water heater electrical disconnect switch.
2. Connect a hose to the drain valve.
3. Locate hose's discharge in an area where hot water will
not cause any damage or injury.
4. Close the cold water inlet valve to water heater.
5. Open a nearby hot water tap to vent the system
6. Open the heater drain valve.
7. If the water heater is being drained for an extended
shutdown, it is suggested the drain valve be left open during
this period.
1. Close the water drain valve by turning the knob or valve
stern clockwise. If alternative water connections are
provided but not used, make certain they are plugged
(i.e. side connections).
2. Open the cold water supply shut-off valve.
3. Open several hot water taps to allow air to escape from
the system.
4. When a steady stream of water flows from the taps, the
water heater is filled. Close the taps and check for water
leaks at the water heater drain valve, combination
temperature and pressure relief valve and the hot and cold
water connections.
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.
The amount of calcium carbonate (scale) released from water is
in direct proportion to water temperature and usage. The higher
the water temperature or water usage, the more scale deposits
are dropped out of the water. This is the limescale, which forms
in pipes, water heaters and on cooking utensils.
Scale accumulation not only reduces the life of the equipment
but also reduces efficiency of the water heater and increases
fuel consumption.
The usage of water softening equipment greatly reduces the
hardness of the water. However, this equipment does not
always remove all of the hardness (scale). For this reason it is
recommended that a regular schedule of de-scaling be
maintained.
The depth of the build-up should be measured periodically.
Water heaters will have about 3 inches of scale build-up when
the level of scale has reached the bottom of the cleanout
opening or about 1 inch of scale build-up if it has reached the
drain valve opening. A schedule for de-scaling should be set up,
based on the amount of time it would take for a ½ inch build-up
of scale.
Servicing 6
59