ICC Mirius, Installation Instructions Manual

Page: 45 / 56

45
Modbus / Gas Water Heaters
Table 38. ModBus Gas Water Heaters Register List
Register Name
(Description) Register Type Address R/W Units
Min
Value
(if W)
Max
Value
(if W)
Primary (Upper) Temperature Input Register 3 R ºC x 512
Lower Temperature
(Lower or Secondary Temperature)
Input Register 4 R ºC x 512
Tank Temperature
(Controlling Tank Temperature algorithmically
calculated)
Input Register 6 R ºC x 512
Setpoint Temperature Holding Register 7 R/W ºC x 512
(ºF)
32.2
(90)
82.2
(180)
SetPoint Differential Holding Register 8 R/W ºC x 512
(ºF)
1.1
(2)
11.1
(20)
CCB Control State Input Register 1040 R/W See Table 39
EMS Status Holding Register 90 R/W See Table 40 (Xi 1.0)
or
Table 41
(MXi)
32.2
(90)
82.2
(180)
EMS Percent Commanded
2 Holding Register 91 R/W % 0% 100%
Fault Code Input Register 1041 R See Table 42 .
Alert Code Input Register 1042 R See Table 42 .
Xi 1.0 Call For Heat Input Status 182 R 0=False
1=True
MXi Call For Heat Input Status 70 R 0=False
1=True
Upper Temperature Probe Open Input Status 65 R 0=False
1=True
Upper Temperature Probe Short Input Status 66 R 0=False
1=True
Temperature Probe ECO status Input Status 156 R 0=Open
1=Closed
Lower Temperature Probe Open Input Status 73 R 0=False
1=True
Lower Temperature Probe Short Input Status 74 R 0=False
1=True
Igniter Current detected
(Xi 1.0 only)
Input Status 148 R 0=No Current
1= OK
Flame Current Input Status149 R 0=No Flame
1-Flame Detected
Blower Prove Pressure Switch
3 Input Status 151 R 0=Open Switch
1=Closed Switch
External Vent Pressure Switch
External T’stat Switch
(Xi 1.0 only, function DIP selectable )
Input Status 152 R 0=Open Switch
1=Closed Switch
Blocked Exhaust Pressure Switch
3 Input Status 153 R 0=Open Switch
1=Closed Switch
Blocked Inlet Pressure Switch
3
Input Status 154 R 0=Open Switch
1=Closed Switch
Low Gas Pressure Switch
3 Input Status 155 R 0=Open Switch
1=Closed Switch
Primary Probe ECO Status Input Status 156 R 0=Open Switch
1=Closed Switch
Flame Sensed Input Status 228 R 0=No Flame
1=Flame Sensed
1. Data is Version encoded into the upper 8 bits and Revision (Lower 8 bits).
2. This limits modulation to maximum EMS Percent Commanded. 100% = Allow up to rated firing (faster recovery). 0% =
minimum modulation rate more efficient but has a slower recovery rate i.e. derates heater capacity).
3. MXi only: Due to hardware design MXi cannot detect switch state when in fault condition and will read 0. In standby any
switch of lower in the limit string than an open switch above it will also appear open. Limit string order is Low Gas Pressure,
Blocked Exhaust, Blocked intake and Blower prove.
4. Data stored in two 16 bit registers “Big Endian” (Higher order bits in lower register number)
5. Hours and Days used together derived from Time (hours x 100). i.e. Elapsed Time of 13612.24 hours in “Days” and
“Hours” = 567 days, 4 hours.