Rinnai
8
EHFA/EHFD HW IM
ANODE
The water heater is fitted with a sacrificial anode to extend it’s life. It will slowly dissipate whilst protecting the
cylinder� The life of the water heater may be extended by arranging for an authorised person to inspect the anode
and replace it if required. It is recommended that the anode be inspected at least every 5 years. The factory fitted
Rinnai anode is Magnesium based� This anode is suitable when the total dissolved solids (TDS) content in the
water supply does not exceed 600 mg/L, which is the case in most areas� In areas where the total dissolved solids
(TDS) content in the water supply exceeds 600 mg/L the Rinnai aluminium based anode is required�
WATER QUALITY
The water quality of most public supplies is suitable for the water heating system� The water quality from bore
wells is generally unsuitable for the water heating system� Refer to the ‘Warranty Conditions’ for water quality
parameters and how they affect the warranty conditions� If in doubt about the water quality, have it checked against
the parameters listed in the warranty conditions� If sludge or foreign matter is present in the water supply, a suitable
strainer filter should be incorporated in the water supply to the system.
OPERATIONAL OVERVIEW
(How the hot water system works)
Single Element Model:
A vitreous enamel lined steel cylinder stores water which is heated by a single
thermostatically controlled heating element, located at the base of the cylinder� The water heater connects directly
to the mains water supply� The heating element can be connected to a Continuous or Off-Peak electricity supply�
The continuous supply is appropriate when the water heater capacity is less than the daily usage of hot water� The
Off-Peak supply is appropriate when the water heater capacity exceeds the daily usage of hot water� The Off-Peak
supply allows heating only for set periods and a volume of water sufficient for daily usage is heated during the set
period and stored� The Off-Peak supply is usually cheaper� Electricity supply types and tariffs vary according to the
local electricity authority�
Twin Element Model:
A vitreous enamel lined steel cylinder stores water which is heated by a twin thermostatically
controlled heating elements, one element is located at the base of the cylinder, while the other is located near the
top� The water heater connects directly to the mains water supply� The bottom heating element heats the whole
contents of cylinder and Top heating element (booster) only operates during the high demand periods to heat the
upper portion of the contents of the cylinder� The two heating elements are wired for non-simultaneous operation,
so that only one heating element can operate at a time� The bottom heating element can be connected to an
Off-Peak electricity supply, and the top heating element to a continuous electricity supply�
Turning Water Heating System ‘OFF’
If the water heater is not going to be used for only a few days, we suggest you leave it switched on� If it is necessary
to switch off the water heater, the switch is usually marked and located in the electricity meter box of the building�
Turning Water Heating System ‘ON’
Switch on the electric supply to the heating elements� The switch is usually marked and located in the electricity
meter box of the building� Water heating will now occur as required� It may take a number of hours before hot water
is available�
DRAINING
WARNING
Draining
MUST BE
carriedoutbyaqualifiedperson.
Watermaybe
HOT
during draining.
Drain the water heater as follows:
1� Isolate or turn ‘OFF’ the water heater at the electricity supply�
2� Close the cold water isolation valve at the inlet to the water heater�
3� Close all hot water taps�
4� Operate the PTR valve easing gear - gently� Operating the PTR valve easing gear will relieve the pressure
in the water heater�
5� Undo the cold water inlet union� Attach a hose to the water heater side of the union� Let the other end of the
hose go to a drain�
6� Operate the PTR valve easing gear again� This allows air into the water heater and will result in water draining
through the hose�
IMPORTANT INFORMATION
