Draining the heater
Due to the shape of the heat exchangers and connecting pipe,
it is extremely difficult to get all of the water out of the heater.
Follow the procedure below to best minimize the chance of
▶ Disconnect electric supply.
▶ Disconnect cold and hot water pipes from fittings on
bottom of heater. Allow water to drain out (have a catch
Remember, these suggestions are only made to help minimize
the potential for freeze damage and are not to be construed as
the guaranteed method for dealing with freeze possibilities.
Check inlet water filter screen once a year
▶ Check that the power is switched off at the circuit breaker
▶ Shut off the installer supplied cold water isolation valve to
the heater. If one is not installed, install before proceeding.
▶ Open nearest hot water tap to relieve pressure in the
▶ Position a bucket under the cold water inlet connection of
the heater to catch any water that may drain.
▶ Disconnect the cold water plumbing connection from the
inlet (bottom right of heater) to access filter screen.
▶ Remove filter, clean with water and inspect for damage. If
the filter is at all damaged, it should be replaced.
▶ Replace the filter into the inlet housing
▶ DO NOT leave the filter out.
▶ DO NOT remove the flow regulator (located behind the
▶ DO NOT clear the filter by back flushing.
▶ NEVER use an air line to blow out the heater (the flow
transducer will be permanently damaged).
▶ Before switching power back on, reconnect cold water
plumbing connection and open all hot water taps and
inspect each tap to ensure all air in the lines has been
purged out. With the air purged and taps still flowing, turn
on all circuit breakers supplying the water heater.
▶ Close all hot water taps and proceed for normal operation.
▶ The maximum flow rate may need to be set again. See
section 4.6.3 for details.
Maintenance | 17
6 720 646 951 (2015/04)