STELPRO · ELECTRONIC THERMOSTATSThe Stelpro space at AirGreenThe Stelpro thermostats we sell, loads checked in Stelpro’s spec sheets, installed by AirGreen in Montreal, Laval, Longueuil, the South Shore and the North Shore.

Hours: Mon–Thu 8 a.m.–6 p.m. · Fri 8 a.m.–4 p.m.

Stelpro · electronic thermostats · checked Oct 14, 2026

Stelpro thermostats: the right model comes down to watts

Every Stelpro line-voltage thermostat has a minimum and a maximum load published by Stelpro, at 120, 208 and 240 V. Add up the watts of your baseboards, pick the voltage: this page shows you the models that fit. Baseboards, fan heaters, heated floors and 24 V, installed by AirGreen across Greater Montréal.

Calculate my load Get a free quotation

4,000 WST402 maximum load at 240 V

±0,5 °Caccuracy stated by Stelpro

5families: baseboards, fan heaters, 347 V, floors, 24 V

1981Stelpro’s roots (Chalair Électrik), in Québec

The Stelpro wattage scale

Load range (min.–max.) of the ST202, ST252, ST302 and ST402 according to Stelpro. Move the slider.

1,750 W · 240 V

ST202

300–2,000 W

ST252

300–2,500 W

ST302

300–3,000 W

ST402

300–4,000 W

At 1,750 W and 240 V: ST202, ST252, ST302 and ST402 fit. Smallest rating that fits: ST202.

AirGreen × STELPROSold and installed by AirGreenBaseboards · fan heaters · floors · 24 VUp to 4,000 W at 240 V±0.5 °C accuracy per StelproQuébec manufacturerMontreal · Laval · Longueuil · South Shore · North Shore

01 · Which Stelpro thermostat

First: what heating are you controlling?

Stelpro makes one thermostat per kind of heater. Pick yours: we show the family and its models, with their product pages.

Baseboards and convectors

Six electronic models. NP = non-programmable, P = programmable. The number gives the maximum load at 240 V: 202 = 2,000 W, 252 = 2,500 W, 302 = 3,000 W, 402 = 4,000 W.

ST202NP

ST252NP

ST302NP

ST402NP

ST302P

ST402P

02 · Wattage calculator

Add up your baseboards, we find the thermostat

Each model is checked against the minimum and maximum load Stelpro publishes for the chosen voltage. AirGreen adds no figure of its own.

1. Type of heater

2. Circuit voltage

3. Programming

4. Wattage of each heater on this thermostat (W)

Heater 1

Heater 2

Add:

Total2,000 Wabout 8.3 A at 240 V

ST202NP300–2,000 W · Non-programmable · 100% of its maximum · Smallest rating that fitsFits

ST252NP300–2,500 W · Non-programmable · 80% of its maximumFits

ST302NP300–3,000 W · Non-programmable · 67% of its maximumFits

ST402NP300–4,000 W · Non-programmable · 50% of its maximumFits

ST302P300–3,000 W · Programmable · 67% of its maximumFits

ST402P300–4,000 W · Programmable · 50% of its maximumFits

STE403NP300–4,000 W · One setback per 24 h · 50% of its maximumFits

Where to find the watts? On the nameplate of each baseboard or fan heater. Stelpro’s rule: several heaters can be connected to one thermostat, but the maximum load must always be respected, and so must the minimum load. The circuit breaker provides overload protection.

AirGreen × STELPRO

Stelpro’s thermostat, AirGreen’s wiring.

Stelpro designs one thermostat per kind of heater and publishes its loads. AirGreen adds up the watts in your home and installs it. Each does what it does best.

What Stelpro brings

One thermostat per heaterBaseboards and convectors, fan heaters (FF), heated floors (Concerto), 24 V and 347 V.
Published loadsMinimum and maximum in watts at 120, 208 and 240 V, in every spec sheet.
±0.5 °C accuracyOn the electronic thermostats, according to Stelpro.
1- to 5-year warrantyDepending on the model, from purchase, as Stelpro writes it.

What AirGreen brings

Sold and installed by AirGreenIn Montreal, Laval, Longueuil, the South Shore and the North Shore.
Free in-home estimateWe look at your heaters, their watts and the wiring on site.
Price on quotationFor the thermostat and its installation.
RBQ 5645-9605-01Subclasses 15.8, 15.10 and 16.

The result: the right Stelpro thermostat for your watts, chosen with you and installed by AirGreen.

Calculate my load Book my free estimate

03 · All loads

Stelpro’s load table, voltage by voltage

Model	For	120 V	208 V	240 V	277 V	347 V	Max. A
ST202NP	Baseboards, convectors	150–1,000 W	260–1,730 W	300–2,000 W	—	—	8.3 A
ST252NP	Baseboards, convectors	150–1,250 W	260–2,160 W	300–2,500 W	—	—	10.4 A
ST302NP	Baseboards, convectors	150–1,500 W	260–2,600 W	300–3,000 W	—	—	12.5 A
ST402NP	Baseboards, convectors	150–2,000 W	260–3,475 W	300–4,000 W	—	—	16.7 A
ST302P	Baseboards, convectors	150–1,500 W	260–2,600 W	300–3,000 W	—	—	12.5 A
ST402P	Baseboards, convectors	150–2,000 W	260–3,475 W	300–4,000 W	—	—	16.7 A
ST252NPFF	Fan heaters	150–1,250 W	260–2,160 W	300–2,500 W	—	—	10.4 A
ST402NPFF	Fan heaters	150–2,000 W	260–3,475 W	300–4,000 W	—	—	16.7 A
ST402PFF	Fan heaters	150–2,000 W	260–3,475 W	300–4,000 W	—	—	16.7 A
STE403NP	Convection, fan heaters	150–2,000 W	260–3,475 W	300–4,000 W	350–4,600 W	400–5,750 W	16.7 A
Concerto STF362	Heated floors	1,800 W max.	3,120 W max.	3,600 W max.	—	—	15 A
STCP · STCNP	Heated floors	1,920 W max.	3,330 W max.	3,840 W max.	—	—	16 A

Resistive load only for the ST models (Stelpro user guides). Stelpro publishes no minimum for the floor thermostats; “Max. A” = maximum current stated by Stelpro. Sources: Stelpro spec sheets 2025-2026, read Oct 14, 2026.

04 · 2, 3 or 4 wires

What is in the box matters too

The number of wires in the wall box changes which model is possible. Never work on a live circuit: connecting a line-voltage thermostat is electrician’s work.

Heater

Wires in the wall box

Two wires in the box: this is the wiring Stelpro shows for its baseboard and convector thermostats.

ST202NP

ST252NP

ST302NP

ST402NP

ST302P

ST402P

STE403NP

05 · Programmable or not

A ST302P’s default program, hour by hour

These are the factory settings Stelpro gives in the ST302P and ST402P guide. Change the day and hour to see the setpoint in force.

17 °C

16 °C

21 °C

12 a.m.6 a.m.12 p.m.6 p.m.12 a.m.

Hour of the day

At 7 a.m.: period “Wake”, setpoint 21 °C.

ST302P · ST402P · ST402PFF

Programmable: up to 4 periods on weekdays and 2 on weekends, three-step programming, settings kept for 2 h during a power outage. Stelpro states up to 20% savings compared to a mechanical thermostat.

ST252NP · ST302NP · ST402NP

Non-programmable with a one-touch ECO mode (temperature setback). Stelpro states up to 12% savings compared to a mechanical thermostat (independent study). The ST202NP: up to 10%.

1 setback

STE403NP · STCNP

One automatic temperature setback every 24 h: handy when the schedule never changes.

06 · Heated floors

Heated floors: Concerto or STCP?

Enter the cable or mat wattage: we work out how many Concerto modules are needed, and whether a STCP is enough on its own.

Heated-floor wattage (W)

Voltage

Concerto1 Concerto thermostat is enough (no expansion unit).3,600 W/mod.

STCP · STCNPSTCP or STCNP: fits (single thermostat).Fits

Concerto: each module (thermostat or STF362XU) handles up to 15 A; Stelpro states that the number of expansion units depends on the total load, with no more than 80 ft (25 m) between two units.

Model	Control	Programming	Setpoint	Sensor
STF362WF	Wi-Fi (Stelpro app), Bluetooth setup	4 weekday + 2 weekend	floor 5–40 °C · room 0–40 °C	15 ft (4.5 m)
STF362PTS	Colour touch screen	Programmable (sheet: 4 + 2)	floor 5–40 °C · room 0–40 °C	15 ft (4.5 m)
STF362P	Buttons	4 weekday + 2 weekend	floor 5–40 °C · room 0–40 °C	15 ft (4.5 m)
STF362NP	Buttons	Non-programmable	floor 5–40 °C · room 0–40 °C	15 ft (4.5 m)
STCP	Buttons	4 weekday + 4 weekend	room 3–35 °C · floor 3–28 °C	13 ft (4 m)
STCNP	Buttons	One setback per 24 h	room 3–35 °C · floor 3–28 °C	13 ft (4 m)

All have a built-in GFCI (Concerto: class A, 5 mA). Sources: Stelpro product pages, spec sheets and quick-start guides, read Oct 14, 2026.

07 · 24 V and mechanical

Low-voltage 24 V and mechanical thermostat

No watts to add up here: these thermostats drive a relay or a furnace, or switch the current directly for the SWT1C.

STE241

24 VAC, 0.5 A · R, W, C · electric furnaces and RE relays · 3–30 °C · one setback per 24 h

ET180

24 VAC, 1 A · R, W · RE, RM, R841D1036 relays · 2 AAA batteries (not included) · 5–35 °C

D010

24 VAC, 1 A · R, W, C · RE, RM, R841D1036 relays and SDHx / SDHR duct heaters · dial 10–30 °C

SWT1C

Line-voltage mechanical · 22 A from 120 to 277 VAC, 1/2 hp · single-pole 2-wire · 10–30 °C. Stelpro also makes a double-pole 4-wire version with an off position (SWT2C).

08 · Warranty

The Stelpro warranty, model by model

As Stelpro writes it, conditions included. Stelpro warranty policy and product documents read Oct 14, 2026.

Models	Stelpro warranty	Document
ST252NP · ST302NP · ST402NP · ST302P · ST402P · ST252NPFF · ST402NPFF · ST402PFF	5 years	Stelpro product pages and 2025-2026 spec sheets. Note: the printed user guides of these models still say 3 years.
ST202NP · STE403NP · Concerto STF362 (WF, PTS, P, NP, XU) · STCP · STCNP · STE241	3 years	Stelpro product pages, sheets and guides.
SWT1C · ET180 · D010	1 year	Stelpro product pages and sheets.

What Stelpro covers

Defects in material and workmanship, from the date of purchase.
Factory repair or replacement, at Stelpro’s option.
No registration required for thermostats (Stelpro’s policy mentions it only for heat pumps and heating cables).

What it does not cover

Disconnection, transport and installation: labour is not covered by Stelpro.
A unit that was modified, misused, badly installed or damaged by accident.
Transferability is not specified by Stelpro: on quotation.

09 · 2026 rebates

2026 rebates: none for these thermostats

Checked on each program’s own site. We would rather tell you plainly.

Program	Stelpro thermostats eligible?	What the program says (Oct 14, 2026)
LogisVert (Hydro-Québec)	No	The participant guide v1.10 (Sept 15, 2026) covers no thermostat.
Hilo	No	Stelpro is not on Hilo’s list of compatible thermostats.
ENERGY STAR	No	The smart thermostat specification excludes line-voltage thermostats; no Stelpro listing.
Énergir	No	The rebate targets an ENERGY STAR Wi-Fi thermostat on central natural-gas heating.
Canada Greener Homes Grant	No	Program closed.

What really applies: a standard. In Québec, the energy-efficiency standards regulation (N-1.01, r. 1) covers line-voltage thermostats (120 to 240 V) that control resistive heating, made since August 15, 2017: they are tested to the CSA C828 standard (thermostats used only for heated floors are excluded). Stelpro’s 2025-2026 spec sheets for the ST252, ST302 and ST402 state CSA C828-19.

10 · Stelpro

A Québec maker of electric heating

Stelpro at a glance

Origins: Chalair Électrik, founded in 1981 in Drummondville
Head office: Saint-Bruno-de-Montarville (QC)
Today: One of Innovair Solutions’ commercial brands, according to Stelpro
Smart thermostats: Maestro, Allia and Ki are discontinued; the only current Wi-Fi model is the Concerto STF362WF (floor)

Compare with other brands

All our thermostats, every brand, are grouped in the Thermostats collection: baseboards, floors, heat pumps and central.

All our thermostats

11 · FAQ

Frequently asked questions about Stelpro thermostats

How do I choose a Stelpro thermostat for my baseboards?

Add up the watts of every baseboard connected to the same thermostat, note the circuit voltage (120, 208 or 240 V), then pick a model whose Stelpro load range covers that total. The calculator in section 02 does the math.

Can several baseboards share one thermostat?

Yes. Stelpro says so: several heaters can be connected to one thermostat, but the maximum load must always be respected.

What happens if the load exceeds the maximum?

Stelpro lists a load that is too high among the causes of an electronic thermostat overheating. Stay within the published range; otherwise, the solution is on quotation.

Why is there a minimum load?

According to Stelpro, both the minimum and maximum loads must be respected for the heater to work properly. At 240 V, the ST minimum is 300 W.

What is the difference between P and NP?

P = programmable (4 periods on weekdays, 2 on weekends). NP = non-programmable; the ST252NP, ST302NP and ST402NP have a one-touch ECO mode.

Which thermostat for a bathroom or entrance fan heater?

An FF model (ST252NPFF, ST402NPFF or ST402PFF), connected on 3 wires. Stelpro’s FAQ states that an FF model cannot be installed on 2 wires for a fan heater.

Does Stelpro make a Wi-Fi baseboard thermostat?

Not at the moment: Maestro, Allia and Ki are on Stelpro’s discontinued list. The only current Stelpro Wi-Fi model is the Concerto STF362WF, for heated floors.

Is there a rebate for a Stelpro thermostat?

Not for a homeowner in 2026: neither LogisVert, Hilo, ENERGY STAR nor Énergir covers these models (section 09).

How long is the warranty?

Depending on the model, 1, 3 or 5 years according to Stelpro, from purchase. Labour (disconnection, transport, installation) is not covered by Stelpro.

My heated floor is over 3,600 W: what now?

With a Concerto, you add STF362XU expansion units: each one handles up to 15 A. The calculator in section 06 gives the number of modules.

What is the STE403NP for?

Circuits from 120 to 347 V, often commercial, up to 5,750 W at 347 V, for convectors and fan heaters (Fan mode). No contactor or relay, according to Stelpro.

How much does an electronic thermostat save?

Stelpro’s figures, compared to a mechanical thermostat: up to 10% (ST202NP), 12% (ST252NP to ST402NP, independent study) and 20% (ST302P and ST402P).

Free quotation