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THM0421 026512 Rev. C Apr 13
Thermann Owner’s Manual
250L to 400L Electric Storage Water Heaters
Plumbing Connections
Pressure & Temperature Relief Valve
The Pressure & Temperature Relief
Valve is supplied loose with the water
heater. The valve rating is:
250L = 1000 kPa
315L = 1000 kPa
400L = 1000 kPa
The PTR valve must be installed directly
into the top socket marked “RELIEF
VALVE”. The drain line from this valve
must run in a continuously downward
direction in a frost-free ambient
position with the discharge end left
open to atmosphere permanently.
The PTR Valve is not intended to enable
connection of the water heater to
supplementary energy sources such as
solar panels or slow combustion stoves
(refer AS/NZS 3500.4 for guidance on
these types of installations).
Open the PTR Valve for approximately
10 seconds by lifting the lever on the
valve to ensure water is relieved to
waste through the relief drain pipe.
Lower lever gently and check that it
closes correctly.
The PTR Valve must not be tampered
with or removed. The water heater
must not be operated unless this valve
is fitted and in working order.
The PTR Valve should be checked for
adequate performance or replaced at
intervals not exceeding 5 years, or less
in areas where local regulations apply.
Important:
The PTR Valve and its drain
outlet pipe must not be sealed or
blocked. It is normal for the PTR valve
to leak a small amount of water during
heating cycles.
Danger
Failure to operate the relief valve
easing lever at least once every six (6)
months may result in a problem with
the water heater and in some cases the
tank may explode.
Warning:
A separate drain line must
be run for this relief valve. It is not
permitted to couple drain lines from
relief valves into a single common
drain line.
Cold Water Connection
An approved isolating valve, non
return valve, line strainer (optional but
recommended), and union must be
fitted between the supply main and the
RP¾/20 socket marked INLET at the
bottom of the water heater. All fittings
must be approved by the relevant
Authority. See the diagram on page 4
for details.
Note for S.A. and W.A.:
It is a state
requirement that a pressure relief valve
be fitted on the cold water supply line
between the non return valve and the
water heater. See the diagram on page
4 for details.
