Rinnai Infinity Series, Installation Manual

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7
When the water temperature is below the set point (normally 60
0
C) the thermostat contacts
(TSTAT1) will close and allow power to the circulating, primary pump.
The pump will start circulating water from the bottom of the storage cylinder up through the Rinnai
Water Heater(s) to be heated and returned to the cylinder. The Rinnai Water Heater(s) see this the
same as a hot water tap opening and will ignite and start heating water. (Rinnai Water Heater(s)
should be pre set to 75
0
C on the dip switches)
When the thermostat reaches its set temperature the thermostat contacts open and the circulating
pump will stop. As water has stopped flowing the Rinnai Water Heater(s) will shut off.
It is normal for the burner on the Rinnai Water Heater(s) to modulate back to a low burner rate as
the water temperature within the storage cylinder rises near to thermostat set temperature.
At times of no demand the primary pump will draw water out of the bottom of the cylinder to reheat it as
and when required due to the heat loss of the vessel.
At times of heavy draw off the mains water will feed into the bottom of the cylinder and into the Rinnai
Water Heater(s). The system has been correctly sized to give the right mix of mains water heated to
75
0
C and mains water straight into the cylinder to have no effect on the overall temperature of the hot
water supply.
The system has been designed to allow for an outlet temperature of 60
0
C with an incoming mains
temperature of 10
0
C
BASIC OPERATING PRINCIPLE