Smart Wi-Fi Thermostat — AFT533D

Name: Smart Wi-Fi Thermostat — AFT533D
Brand: ACE FORGE HVAC

A 24V Wi-Fi thermostat with native HRV / ERV control, dual-fuel support and humidity management — designed for Canadian homes and cold-climate performance.

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AFT533D smart Wi-Fi thermostat, 4.3 inch colour touchscreen showing temperature, ventilation and humidity

Specifications

Smart Wi-Fi Thermostat — AFT533D — key specifications
Parameter	Value
Model	AFT533D
Compatibility	Most 24V heating and cooling systems — furnaces, air conditioners, boilers, heat pumps (forced air or radiant)
Conventional systems	2-stage heating, 2-stage cooling
Heat pump systems	2-stage heating, 2-stage cooling, 2-stage auxiliary / alternative heat, emergency heat
Dual fuel / hybrid heat	Supported
Humidifier / dehumidifier	1-wire or 2-wire (HUM, DEHUM) — up to two accessories
Display	4.3 in. full-colour LCD touchscreen, 480 × 800
On-board sensors	Occupancy, temperature, humidity
Power supply	24 VAC, 50/60 Hz
Desired temperature range	40–90°F (4.5–32°C)
Temperature accuracy	±1°F (±0.5°C)
Operating temperature	14–122°F (−10–50°C)
Humidity range	5–95% RH non-condensing, ±5% accuracy
Connectivity	Wi-Fi 802.11 b/g/n @ 2.4 GHz; BLE for pairing; 915 MHz radio for up to 6 remote sensors
Thermostat dimensions	143 (L) × 82 (W) × 21 (H) mm
Trim plate dimensions	170 (L) × 110 (W) × 6 (H) mm
Mounting	Wall mounting
TF card slot	Firmware updates and log collection (FAT32)
Accessories	Trim plate; C-wire adapter (optional); remote zone sensor
Remote zone sensor	915 MHz, temperature + humidity, 2 × AAA batteries, tabletop or wall mounting

Values as published in the 2026 product catalogue. Ask us for the model-level submittal sheet before specifying.

Features

✓Native HRV / ERV control built in — ventilation modes OFF / ON / AUTO
✓Ventilation mode assignable to each scheduled period
✓Ventilation outdoor-temperature lockout, with configurable minimum
✓Humidity frost protection — lowers the indoor humidity target as outdoor temperature falls, to help prevent window condensation
✓Furnace + HRV intelligent interlock control
✓One thermostat controls multiple HVAC accessories: humidifier, dehumidifier or ventilation
✓CWA terminal can drive a 24V powered accessory when not used for the C-wire adapter
✓7-day customisable fan and temperature programming schedule
✓Multiple hold options: permanent hold, temporary hold, follow schedule
✓Circulate mode — fan periodically circulates air
✓Preheat or precool to reach the scheduled temperature on time
✓Daily, weekly and monthly energy usage reporting
✓Comfort preset support and adjustable temperature differential
✓Lock feature to prevent accidental changes
✓Maintenance reminders
✓Remote zone sensors balance hot and cold spots throughout the home
✓Voice assistant integration (Alexa, Google Assistant) and IFTTT support

Overview

The AFT533D is a 24 VAC Wi-Fi thermostat for North American heating and cooling systems. Its distinguishing feature is native HRV / ERV control: ventilation modes OFF, ON and AUTO are handled by the thermostat itself rather than a separate wall control, and a ventilation period can be assigned inside each schedule period. It also manages a humidifier or dehumidifier — up to two accessories on the HUM and DEHUM terminals.

It suits most 24 V systems: furnaces, air conditioners, boilers and heat pumps, forced air or radiant. Conventional systems go to 2-stage heating and cooling; heat pump systems add 2-stage auxiliary and emergency heat, and dual fuel is supported. Because it works on 24 V control logic, it drops into an existing low-voltage installation.

Where it is used

Residential replacement where the thermostat also switches an HRV or ERV
Dual-fuel installations pairing a furnace with a heat pump outdoor unit
Homes with a humidifier or dehumidifier driven from the same device
Room-to-room balancing using up to six 915 MHz remote zone sensors
Cold-climate housing needing ventilation lockout and humidity frost protection

Selection & installation notes

01
Confirm the system type first: conventional 2H/2C, heat pump 2H/2C plus 2-stage auxiliary, and dual fuel are all covered, but existing wiring determines whether a C-wire adapter is needed.
02
The remote zone sensor runs at 915 MHz on 2 × AAA batteries, tabletop or wall-mounted, so agree placement with the homeowner rather than at commissioning.
03
Accessory terminals cover up to two of humidifier, dehumidifier or ventilation. On a job needing all three, plan a separate control for the third.
04
Set the ventilation outdoor-temperature lockout with the installer; the minimum is configurable and should follow the local design condition.

Common questions

Does this thermostat control an HRV or ERV directly?

Yes. Ventilation control is built in, with OFF / ON / AUTO modes, ventilation assignable to each scheduled period, an outdoor-temperature lockout and a furnace + HRV interlock. No extra ventilation wall control is required.

Can it replace the thermostat on a dual-fuel system?

Dual fuel and hybrid heat are supported, as are conventional 2-stage systems and heat pumps with 2-stage auxiliary and emergency heat. Verify terminal usage against the existing wiring before ordering.

Do I need the C-wire adapter?

Not always — it is optional. Where no C wire is available, the CWA terminal can instead drive a 24 V powered accessory, so the two cannot be used together on one installation.