verified connector library

Honeywell SOLA R7910 hydronic/steam control

Register map(s) for this device, each at the trust rung it earned. Addresses are 0-based as on the wire; word order and scaling are only confirmed at the hardware-verified rung.

interop-verified

Read + decoded cleanly over a real network vs an independent third-party Modbus test server (transport and framing; reads are remapped into the server's register window, so the map's own addresses are NOT exercised). Does NOT prove word order/scaling against the actual device.

pointaddress (0-based)typescaleunit
status_change0U161
digital_io2U161
limits4U161
demand_source6U161
outlet_sensor_temp7U160.1°C
firing_rate8U160.1%
fan_speed9U161RPM
flame_signal10U160.01V
inlet_sensor_temp11U160.1°C
dhw_sensor_temp12U160.1°C
s5_sensor_temp13U160.1°C
stack_sensor_temp14U160.1°C
remote_control_input_ma15U160.1mA
active_ch_setpoint16U160.1°C
active_dhw_setpoint17U160.1°C
active_ll_setpoint18U160.1°C
steam_pressure20U160.1psi
analog_modulation_input21U160.1mA
active_ch_pressure_setpoint22U160.1psi
active_ch_operating_point25U160.1°C
active_dhw_operating_point26U160.1°C
active_lead_lag_operating_point27U160.1°C
active_system_operating_point28U160.1°C
active_system_setpoint29U160.1°C
burner_control_status32U161
burner_control_state33U161
lockout_code34U161
sequence_time38U161s
delay_time39U161s
burner_control_flags41U161
outlet_operation_temp43U160.1°C
dhw_operation_temp44U160.1°C
stack_or_heat_exchanger_operation_temp45U160.1°C
ch_status64U161
ch_requested_rate68U160.1
dhw_status80U161
dhw_requested_rate85U160.1
burner_cycle_count128U32BE1
burner_run_time130U32BE1
ch_pump_cycle_count132U32BE1
dhw_pump_cycle_count134U32BE1
system_pump_cycle_count136U32BE1
boiler_pump_cycle_count138U32BE1
outdoor_temperature170U160.1°C
outlet_t_rise_rate172U160.1°C/s
exchanger_t_rise_rate173U160.1°C/s
s10_sensor_reading174U160.1°C

link settings as documented (unverified): RTU; default 38400 8N1; FC 03,06,16,17; RS-485 half duplex, LSB first, idle line for 3.5 or more characters.

bench facts as documented (unverified)
terminals3-pin connector
A/B polarityTerminal 1: Data + (a), Terminal 2: Data - (b), Terminal 3: Common (c)
connector3-pin connector
wiring notesMB1 or MB2 Modbus ports
max registers/read125
sentinel values0x8FFF for unconfigured temperature parameters, 0x7FFF or 0x8200 for no sensor configured, 0x8000 for shorted, 0x8100 for open, 0x8300 for outside high range, 0x8400 for outside low range, 0x8500 for not reliable.
protocol notesExcept for variable length data items, registers can be accessed as a single register or up to 20 registers for writes and 125 registers for reads. Variable length data must be accessed individually.
model register176
firmware register186
identification notesReport Slave ID (FC17) returns OS number and Burner name. OS number is also at register 186, Burner name is at 183.
FC 43 device IDnot supported
doc revision4.1.1

generated by gemini:gemini-3.5-flash · harvested from https://www.ccontrols.com/support/dp/OEMModbusSIS4_1_1_1_1.pdf (Honeywell); manual-faithful — the document's claims, panel risk: ELEVATED — panel is not confident; proved interop-verified on 2026-06-10 · recorded 2026-06-10

The trust ladder

Each rung states what it proved and what it did not. Gray until proven; green is earned by hardware only.

Have a device that isn't here? Upload its register map — generation is free, and the connector earns its rung by being proven, not claimed.

Need it proven on your own device? Hardware verification — if it doesn't verify, you don't pay.

Building a platform? License the verified library — machine-readable maps, firmware matrix, API access.