Specifications

TM013 Vulcan Electric Service Instructions REV: D
D.O.I.: 05/09
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Operation
Single Element Models
Water temperature is maintained via a thermostat switching the active conductor to an
electric immersion element positioned towards the bottom of the cylinder.
When the water temperature within the cylinder falls sufficiently the thermostat contacts
close suppling power to the element.
Once the water temperature reaches the set point of the thermostat, the contacts open
cutting power to the element.
A double pole „manual reset‟ over temperature cut out is incorporated into the thermostat
to provide additional protection in the event the controlling thermostat contacts fail. The
ECO contacts open between 80ºC and 88ºC.
Twin Element Non-Simultaneous Models
Water temperature is maintained via two (2) electric immersion elements, one (1)
positioned near the top of the cylinder and the other towards the bottom. Only one element
is operational at any time (known as non-simultaneous operation).
A thermostat, positioned adjacent to each element is utilized to maintain water
temperature.
The top thermostat switches the neutral from the top element to the bottom element, this
ensures only one element can be energised at a time. The top thermostat is factory set at
60ºC. The bottom thermostat switches the active to the bottom element only.
Both thermostats incorporate a double pole „manual reset‟ ECO to provide additional
protection in the event the controlling thermostat contacts fail.
Once the top thermostat senses a temperature of approximately 60ºC the thermostat
contacts open the neutral circuit to the top element (between terminals 1 and 2), causing
the top element to be de-energised, and close the neutral circuit to the bottom element
(between terminals 1 and 5).
When the water temperature at the bottom of the tank reaches the set point of the bottom
thermostat, the thermostat contacts open cutting the active circuit to the bottom element.
Under normal usage the top element is unlikely to operate, the water temperature being
maintained by the bottom element. During periods of heavy use when the complete supply
of hot water is depleted the top element will operate to maintain the water temperature at
the top of the tank.
When the bottom element is connected to an off peak tariff full recovery of the tank will
occur whenever power from the off peak tariff is available, usually overnight.