Справочник Пользователя для Rheem 300 series

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CONNECTIONS – PLUMBING 
22 
RELIEF VALVE DRAIN 
A copper drain line must be fitted to the relief valve to carry the discharge clear 
of the water heater. Connect the drain line to the relief valve using a 
disconnection union. The pipe work from the relief valve to the drain should be 
as short as possible and fall all the way from the water heater with no 
restrictions. It should have no more than three right angle bends in it. Use 
DN15 pipe. 
 
The outlet of the drain line must be in such a position that flow out of the pipe 
can be easily seen (refer to AS/NZS 3500.4) - but arranged so hot water 
discharge will not cause injury, damage or nuisance. The drain line must 
discharge at an outlet or air break not more than 9 metres from the relief valve. 
 
In locations where water pipes are prone to freezing, the drain line must be 
insulated and not exceed 300 mm in length. In this instance, the drain line is to 
discharge into a tundish through an air gap of between 75 mm and 150 mm. 
 
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. 
 
EXPANSION CONTROL VALVE 
Local regulations may make it mandatory to install an expansion control valve 
(ECV) in the cold water line to the water heater. In other areas, an ECV is not 
required unless the saturation index is greater than +0.4 (refer to 
Supplies”
 on page 30). However, an ECV may be needed in a corrosive water 
area where there are sufficient quantities of silica dissolved in the water. 
 
The expansion control valve must always be installed after the non return valve 
and be the last valve installed prior to the water heater 
page 
20
)
. A copper drain line must be run separately from the drain of the relief 
valve.