Rinnai Infinity Series, Installation Manual

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EXTRA PUMP
For some systems two pumps should be used. If
this is the case they should be piped in parallel
with equal pipework to both pumps. They Should
be controlled by the same thermostat so that if
one is on then they are both on
EXTRA CYLINDER
For some systems two hot water storage cylinders are used. This is common for large retro fits where
the necessary size of tank will not pass through a doorway or fit in to the space where it s to be
installed. When two tanks are used they must be piped in a pyramid pipework layout. The reverse
return pipework method will not balance the systems because of the bidirectional pipework. Two control
thermostats (TSTAT1) should be used. The pump should not come on until BOTH thermostats are
below the set point. Two high limit stats (TSTAT2) must be used and the system should trip if either
Stat reaches the high limit temperature.
Additionally a two tank system will also require TWO T & P Valves, each one to exceed the capacity of
the largest heater (based on the temperature scale)