Electronic Thermostat STELPRO STE403NP 4000 W | Montreal, Laval, Longueuil, South Shore and North Shore

Commercial buildings, institutions and apartment buildings don't always use the same voltages as a house. You'll find heaters there powered at 277 V or 347 V, which most residential thermostats aren't suited for. The Stelpro STE403NP was designed to cover that full range: it runs from 120 V up to 347 V and controls convectors as well as fan heaters. It's an electronic thermostat with a single programming feature that automatically lowers the temperature once per 24-hour period. At AirGreen, we install it in offices, stores, hallways and common areas where you need rugged, versatile control.

A versatile thermostat for 120 to 347 V buildings

The STE403NP's electrical versatility is its first strength. It accepts 150 to 2000 W at 120 V, 260 to 3475 W at 208 V, 300 to 4000 W at 240 V, 350 to 4600 W at 277 V and 400 to 5750 W at 347 V. That means one model can be used throughout a building that combines several voltages, which simplifies purchasing and maintenance for a property manager.

Convectors and fan units

The STE403NP controls convection heaters as well as forced-air units, thanks to its fan mode. That compatibility is useful in entrances, stairwells and vestibules, which are often heated by fan heaters that need to quickly warm up the cold air coming in through the door.

The automatic daily setback

The STE403NP doesn't offer a full weekly schedule. Instead, it offers single programming: an automatic temperature setback once per 24-hour period. In practice, this feature suits spaces whose occupancy follows a simple daily cycle, like an office that's closed at night or a commercial unit. The temperature drops automatically while the space is unoccupied, without anyone having to think about it every evening.

Freeze warning and safety mode

In a building, some rooms sit empty for long periods. The freeze warning signals a temperature low enough to pose a risk of freezing, so you can step in before the plumbing gets damaged. Safety mode locks in a maximum set point, a very useful feature in common areas, hotel rooms or apartments where you want to keep the heat from being pushed to the max.

Precision and an extended range

Thermistor sensing holds the temperature within ±0.5 °C (1 °F). The set point range goes down to 3 °C and up to 30 °C (37 to 86 °F), so you can keep an unoccupied space above freezing with a very low set point. The digital display works in °C or °F. The thermostat is certified to CSA C828-13 and comes in a white moulded plastic casing.

A wide range of uses

We install the STE403NP in offices, retail stores, clinics, community halls, and the hallways and stairwells of apartment buildings, as well as in mechanical rooms where the only goal is to keep the temperature above freezing. Its high capacity at 347 V also lets it control high-wattage units in large spaces with a single thermostat.

Compared with residential models

Stelpro's residential thermostats, like the ST402NP or the ST402P, are limited to 120, 208 and 240 V. The STE403NP stands out with its range up to 347 V, its compatibility with fan units and its automatic daily setback. For a house heated with 240 V baseboards, the residential models are enough; for a commercial building or an apartment building supplied at 277 or 347 V, the STE403NP is the right tool.

Technical specifications

• Type: electronic line-voltage thermostat, single programming (automatic setback once every 24 hours)
• Systems: convection heaters and fan heaters
• Voltage: 120 to 347 V
• Load range: 150 to 2000 W at 120 V; 260 to 3475 W at 208 V; 300 to 4000 W at 240 V; 350 to 4600 W at 277 V; 400 to 5750 W at 347 V
• Display: digital, °C or °F (selectable)
• Accuracy: ±0.5 °C (1 °F), thermistor sensing
• Set point: 3 to 30 °C (37 to 86 °F)
• Functions: fan mode for forced-air units, freeze warning, safety mode (maximum set point lock)
• Certification: CSA C828-13
• Colour: white, moulded plastic

Installation by AirGreen in commercial and multi-unit buildings

In a commercial building, the first step is to identify the voltage of each heating circuit and the type of unit being controlled. Our qualified technicians note this information, check that the load falls within the STE403NP's range for that voltage, then go ahead with the installation, with the circuit shut off and the absence of voltage confirmed. Fan mode is turned on when the unit is a fan heater. We then set up the automatic daily setback, safety mode and, if needed, a low set point for unoccupied spaces.

For a property manager, we can plan the replacement of several thermostats in phases, to limit the impact on occupants.

Cutting a building's consumption

In a commercial space, the automatic daily setback does most of the work: the temperature goes down overnight, with no one lifting a finger. Safety mode prevents set points that are too high in common areas. In unoccupied spaces, a set point around 3 to 5 °C, combined with the freeze warning, protects the building while keeping consumption to a minimum. Applied across a whole building, these settings make a real difference on the winter bill.

Maintenance

Dust the fan heaters regularly, since their grille and fan collect dust. The thermostat itself only needs an occasional cleaning.

Why AirGreen

AirGreen is a family-owned HVAC company that holds an RBQ licence, with more than 15 years of experience in residential and commercial work. To buy the Stelpro STE403NP thermostat and have it professionally installed, contact us. We serve Montreal, Laval, Longueuil, the North Shore and the South Shore.

Stelpro documents

Stelpro spec sheet (PDF) · Stelpro user guide (PDF)