Rinnai Circ-Logic RU98i - Circ-Logic System Details; Benefits of Circ-Logic; Compatible Rinnai Water Heaters

2 Rinnai Circ-Logic™ with Grundfos Kit
Rinnai Water Heaters that Incorporate Circ-Logic™
The table below indicates the beginning serial number for each model that has the Circ-Logic™ feature.
Model Serial Number Part Number
RL75i (VC) REU-VC2528FFUD-US(A) Units with an "(A)" on the end of the part
number.
RL75e (VC) REU-VC2528WD-US(A)
RL94i (VC) DB.CA-016788 and higher REU-VC2837FFUD-US
RL94e (VC) DC.BA-013335 and higher REU-VC2837WD-US
RU98i DB.BA-006175 and higher REU-KB3237FFUD-US
RU98e DB.BA-006213 and higher REU-KB3237WD-US
RU80i DB.BA-006201 and higher REU-KB2530FFUD-US
RU80e DB.BA-006195 and higher REU-KB2530WD-US
Benets of Circ-Logic™:
Energy Eciency: Circ-Logic™ enables the homeowner to use the Economy Mode and thus cycle the
pump less oen, using less energy to maintain loop temperature.
Greater Comfort: If desired, the Comfort Mode can be used to re-heat the circulaon loop more fre-
quently and thus ensure the temperature remains high, even in high-heat loss loops.
Improved Durability: By reducing overall cycle frequency, Circ-Logic™ helps to limit wear on the internal
workings of the tankless unit. With the Grundfos GTK15 kit, wear and tear is further
minimized because the system is only acve when you want it to be.
Table of Contents
Benets of Circ-Logic™ ...................................... 2
Rinnai Water Heaters that
Incorporate Circ-Logic™ ..................................... 2
Kit Contents ....................................................... 3
Disclaimers ......................................................... 3
Rinnai Circ-Logic™ Descripon .......................... 4
Pipe Length ........................................................ 5
System Drawings ................................................ 5
Pump Installaon ............................................... 7
Wiring Pump to the Water Heater ..................... 8
Timer Technical Data ........................................ 10
Timer Technical Applicaon ............................. 10
Timer Operaon ............................................... 10
Troubleshoong ............................................... 11
Sequence of Operaon .................................... 11