Rinnai Circ-Logic™ Description - Rinnai Circ-Logic Series Manual

Rinnai Circ-Logic™ Description
How It Works
DIP switches (SW2 - white switches, #4, #8) should be set
correctly for recirculation and mode. The Rinnai water heater
should be turned on.
Pump recirculation begins when the water heater is turned on.
The Rinnai inlet and outlet thermistors measure the water
temperature.
The water heater produces hot water at the temperature
setting. If the inlet thermistor detects abnormal temperature
then diagnostic code 51 is generated and the pump will turn off.
When the return water temperature reaches approximately 15°
F (8.3°C) below the temperature setting, the water heater and
pump will turn off.
The cycle will start at the approximate time interval in the table.
The cycle stops based on the temperature thermistor readings.
The Logic has two modes of operation: Comfort and Economy.
Economy Mode
Economy Mode uses longer time intervals (about twice as long
as Comfort Mode) and can be used for two purposes: to reduce
the energy consumption required to keep the loop warm and/or
to maintain temperature in a loop that is well insulated.
Economy Mode operates as follows:

Less energy consumed due to fewer pump cycles

Pump cycles on every 31 to 79 minutes (see table)

The time intervals are based on the assumption that the
loop is insulated.
Comfort Mode
Comfort Mode has shorter time intervals and can be used to
either ensure the loop is always kept hot or to cope with a loop
that has a high degree of heat loss due to lack of insulation, or
pipes that run through a concrete slab, etc. Comfort Mode
operates as follows:

Higher energy consumption due to more pump cycles

Pump cycles on every 15 to 39 minutes (see table)

The time intervals are based on the assumption that the
loop IS NOT insulated.
Rinnai
Temperature
Setting
°F
140
135
130
125
120
115
110
108
106
104
102
100
98
* The pump will cycle on at these
calculated intervals which are based on
the temperature setting, insulation, and
estimated heat loss in the system. The
values for your installation may vary.
4 Rinnai Circ-Logic™ with Grundfos Kit
Typical Pump ON
Intervals*
(minutes)
Economy Comfort
Mode Mode
31 15
31 15
31 15
31 15
31 15
35 18
42 21
45 22
49 24
54 27
60 30
68 34
79 39