Rinnai Circ-Logic RU98i User Manual

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

Rinnai Circ-Logic RU98i Specifications

General

Category	Tankless Water Heater
Model	RU98i
Gas Type	Natural Gas or Propane
Energy Factor	0.95
Maximum Flow Rate	9.8 GPM
Minimum Flow Rate	0.26 GPM
Activation Flow Rate	0.4 GPM
Circ-Logic	Yes
Heat Exchanger	Stainless Steel
Maximum BTU Input	199, 000 BTU
Minimum BTU Input	15, 000 BTU/h
Temperature Range	98°F - 185°F
Vent Length	Up to 65 feet
Electrical Requirements	120V AC
Ignition System	Electronic
Warranty	12-year on heat exchanger, 5-year on parts, 1-year on labor