Proportional room controller for SPC fan convectors and trench units
The SPC Modulo controller is a wall mounted room thermostat that sets the speed of a heater’s EC/DC fans with a 0 to 10V signal. You set the room temperature on its touch fascia, and Modulo slows the fans as the room warms up and stops them when the setpoint is reached, matching heat output to what the room needs.
Supplied by S & P Coil Products Limited (SPC), Modulo is a control option for Belgravia Classic, Belgravia Supreme and Belgravia Tilevector Fan Convectors and Metropolitan Powered trench units, in schools, libraries, leisure centres, offices and other commercial and public buildings. Options include a relay box to close a water valve at setpoint and a lockable tamperproof case.
Proportional fan speed
0 to 10V speed signal to EC/DC fans
Touch fascia
Wake it, then set the room temperature by touch
Valve control option
Relay box closes a water valve at setpoint
Lockable case
Curved tamperproof case restricts the setpoint
4°C band
Fan speed varies continuously across 4°C below setpoint (17 to 21°C at a 21°C setpoint), and the fan stops at setpoint.
0 to 10V
Speed signal to the heater’s EC/DC fans: 8V at the bottom of the band, falling to 2V near setpoint and 0V at setpoint.
24V DC
Normally powered from the heater it controls, so no separate mains supply is needed at the controller. 0.6 W maximum.
80 x 80 mm
White plastic housing, 20 mm deep, for surface mounting or flush mounting in a standard back box.
What is the SPC Modulo controller?
The SPC Modulo controller is a room thermostat and fan speed controller in one. It is mounted on the wall of the room and wired back to the heater it controls, which normally provides its 24V DC supply. Modulo senses the room temperature and sends a 0 to 10V signal to the heater’s EC/DC fans, setting how fast they run.
Modulo uses proportional control. Across a 4°C band below the setpoint, the fan speed changes continuously: the fans run at their maximum set speed when the room is 4°C or more below setpoint, slow down as the room warms and stop when it reaches setpoint. With a 21°C setpoint, the band runs from 17°C to 21°C. Users only set the temperature: a touch on the top right of the fascia wakes the controller, and the touch areas at the bottom left and right lower and raise the setpoint. No other settings are needed.
How the SPC Modulo controller varies fan speed across the proportional band below setpoint, with the fan off at setpoint.
Which SPC products does the Modulo controller work with?
The SPC Modulo controller is designed for SPC fan-assisted heaters with EC/DC fans that take a 0 to 10V speed signal. SPC literature lists Modulo as a control option for these ranges:
Floor, wall and ceiling mounted fan convectors. An extended casing houses the Modulo valve inside the unit.
Fan convectors with a rounded casing. An extended casing (not available on Supreme Plus) houses the Modulo valve inside the unit.
Ceiling fan convectors for 600 mm grids. With Tilevector, the Modulo valve is fitted outside the unit.
Fan-assisted trench heaters for full height glazing, with EC/DC fans set by a 0 to 10V signal from a room controller or BMS.
Fan-assisted trench units for cooling, or heating and cooling, with EC/DC fans set by a 0 to 10V signal.
SPC Modulo controllers have been specified on projects across the UK, including Newport Central Library, Wantage Leisure Centre, Bickleigh Down C of E Primary School and the Museum of Two Halves, Wrexham. Read more about the ranges on our Belgravia Fan Convectors and Trench Heating and Cooling pages.
SPC Modulo controller options and installation
As standard, the SPC Modulo controller controls the fans. For waterside control as well, an optional relay box with a volt-free contact lets Modulo close an on/off water valve when the room reaches setpoint, so hot water stops flowing to the heater.
- The relay box is pre-installed inside the heater and wired back to Modulo, and a specific wiring diagram is issued for it, so specify it with the heater.
- On Belgravia Classic and Belgravia Supreme units, an extended casing houses the valve inside the unit. On Belgravia Tilevector, the valve is fitted outside the unit.
- Valves and actuators supplied by SPC are supplied loose for fitting on site.
Two cases are available for the SPC Modulo controller, depending on how much protection the location needs.
- Standard square case: a simple, ventilated cover giving basic protection for general installations.
- Curved tamperproof case: a ventilated, transparent cover with a lock, to prevent unauthorised access to the controller where the setpoint must not be changed.
If the lockable cover is used, Modulo must be flush mounted.
Standard square case
Curved tamperproof case
- Mount the SPC Modulo controller where it senses a representative room temperature: about 1.5 m above floor level, away from direct sunlight and other heat sources.
- It can be surface mounted, or flush mounted in a standard back box using the frame and adaptor plate supplied.
- Wiring runs between the heater and Modulo’s terminal blocks, following the wiring diagram supplied with the order.
- An older Modulo can be replaced using the same four wires. IOM 89 shows where each wire connects.
Watch the installation video for the fitting and wiring steps.
SPC Modulo controller specification summary
| Feature | SPC Modulo controller |
|---|---|
| Type | Wall mounted proportional thermostat and fan speed controller |
| For use with | Fan-assisted heaters with EC/DC (brushless DC) fans that accept a 0 to 10V DC speed signal: Belgravia Classic, Supreme and Tilevector Fan Convectors; Metropolitan Powered trench units |
| Control output | 0 to 10V DC fan speed signal: 8V at 4°C below setpoint, falling to 2V near setpoint and 0V at setpoint |
| Proportional band | 4°C below setpoint |
| Interface | Touch fascia with temperature display; touch areas to wake the controller and to lower or raise the setpoint |
| Power supply | 24V DC ±10%, normally provided by the heater |
| Maximum power consumption | 0.6 W |
| Accuracy and resolution | ±1°C accuracy, 0.1°C resolution |
| Ambient temperature | 0 to 60°C |
| Protection | IP20 |
| Housing | White plastic, 80 x 80 x 20 mm |
| Mounting | Surface or flush, with frame mounting kit and adaptor plate for a standard back box; about 1.5 m above floor level |
| Options | Relay box with volt-free contact for an on/off water valve; standard square case; curved lockable tamperproof case (flush mounting required) |
| Compliance | LVD 2014/35/EU, EMC 2014/30/EU |
| Maintenance | Dust with a dry cloth only; no liquids, cleaners or solvents |
| Supplied by | S & P Coil Products Limited (SPC), Leicester, UK |
Ask about the SPC Modulo controller
Choosing controls for fan convectors or trench heating in a school, office, library or other commercial or public building? Tell us about your project and we will help you choose the right controls. Call 0116 249 0044 or email spc@spc-hvac.co.uk.
Frequently Asked Questions
Both. The SPC Modulo controller senses the room temperature like a room thermostat, then sets the speed of the heater’s EC/DC fans with a 0 to 10V signal, rather than simply switching the heater on and off. Users only set the room temperature; Modulo adjusts the fan speed itself.
An on/off thermostat runs the fan until the room reaches setpoint, switches it off, then switches it back on when the room cools. Proportional control varies the fan speed with how far the room is from setpoint. The SPC Modulo controller runs the fans faster when the room is cold, slows them across a 4°C band as the room warms and stops them at setpoint, matching heat output to the load for steadier room temperatures. Energy savings on a project depend on the building and how it is used.
Yes, with the optional relay box. Its volt-free contact lets the SPC Modulo controller close an on/off water valve when the room reaches setpoint. The relay box is pre-installed inside the heater and wired back to Modulo, so it needs to be specified with the heater.
Yes. An older SPC Modulo controller can be swapped for the current Modulo using the same four wires, and IOM 89 shows where each wire connects on the terminal block. Installation instructions for older Modulo controllers are on our Literature page.
No. Electric Belgravia Fan Convectors are controlled on/off by a switch, remote thermostat or BMS, and Metropolitan Electric Trench Heaters run their fans at a fixed speed set in the factory, with on/off control from a switch, thermostat or BMS. The SPC Modulo controller is for the SPC units listed above, whose EC/DC fans take a 0 to 10V speed signal.
Yes. Belgravia Fan Convectors can be specified with a relay for a remote enable/disable signal from a BMS, or with on/off and fan speed control from a 0 to 10V BMS signal. Metropolitan Powered trench units take their fan speed from a 0 to 10V signal from a BMS or a room controller. The SPC Modulo controller suits rooms that need their own wall mounted controller.
When it has power, the SPC Modulo controller shows a dim green light in the top right corner of the fascia, and it returns to this standby state a few seconds after the temperature is set. Touch the green light to wake it. If there is no green light, the controller is not receiving power: check the 24V DC supply, which is normally inside the heater. For any other problem, contact SPC on 0116 249 0044.
