Specifications

CONNECTIONS – PLUMBING
41
RELIEF VALVE DRAIN
DN15 copper drain lines must be fitted to the temperature pressure relief valve, expansion control valve (if
one is installed) and solar circuit relief valve to carry the discharge clear of the water heater. Connect the
drain lines to the valves using disconnection unions. The drain line from the valve to the point of discharge
should be as short as possible, have a continuous fall all the way from the water heater to the discharge
outlet and have no tap, valves or other restrictions in the pipe work.
A drain line from a relief valve must comply with the requirements of AS/NZS 3500.4.
A drain line must be no longer than 9 metres with no more than three bends greater than 45° before
discharging at an outlet or air break. The maximum length of 9 metres for a drain line is reduced by 1 metre
for each additional bend required of greater than 45°, up to a maximum of three additional bends. Where the
distance to the point of final discharge exceeds this length, the drain line can discharge into a tundish.
Subject to local regulatory authority approval, the drain lines from the temperature pressure relief valve and
expansion control valve from an individual water heater may be interconnected.
The outlet of a drain line must be in such a position that flow out of the pipe can be easily seen, but arranged
so discharge will not cause injury, damage or nuisance. The termination point of a drain line must comply
with the requirements of AS/NZS 3500.4. Drain lines must not discharge into a safe tray.
In locations where water pipes are prone to freezing, drain lines must be insulated, must not exceed 300 mm
in length and are to discharge into a tundish through an air gap of between 75 mm and 150 mm.
If a drain line discharges into a tundish, the drain line from the tundish must be not less than DN20. The drain
line from a tundish must meet the same requirements as for a drain line from a relief valve.
Warning: As the function of the temperature pressure relief valve on this water heater is to discharge
high temperature water under certain conditions, it is strongly recommended the pipe work downstream of
the relief valve be capable of carrying water exceeding 93°C. Failure to observe this precaution may result in
damage to pipe work and property.
SOLAR INLET AND OUTLET
All pipe work must be cleared of foreign matter before connection and purged before attempting to operate
the water heater. All olive compression fittings must use brass or copper olives. Use thread sealing tape or
approved thread sealant on all fittings.
The solar cold outlet and solar hot inlet connections are located at the top of the solar storage tank.
Notes:
It is important not to cross connect the solar cold and solar hot pipes to the incorrect connections.
 The solar cold pipe connects to the bottom of the solar collector and the solar hot pipe connects to
the top of the solar collector on the opposite side to both the solar cold pipe connection and the hot
sensor connection.
 The solar hot inlet connection is located in the centre of the top of the solar storage tank (the
connection is marked by a label on top of the storage tank).
 The solar cold outlet connection is located at a corner of the top of the solar storage tank (the
connection is marked by a label on top of the storage tank).
Connect the solar pipes to the solar storage tank using only the fittings supplied.