2 Wire Smart Thermostat

Yes. The Mysa Trim Kit (sold separately) includes a mounting plate designed for standard electrical junction boxes.

Yes. Installation requires basic comfort with electrical wiring at your furnace or boiler. Our online guide creates custom instructions for your exact setup with 11 different wiring diagrams. If you're uncomfortable working with HVAC wiring, hire a qualified technician—typically $75–150.

Only with Mysa Smart Thermostat.  Does not work with other Mysa products (Baseboard, In-Floor) or other smart thermostat brands.

Yes. Mounting to drywall? Use only the Trim Plate. The adapter is there if you need it.

No. While Mysa for Central HVAC features a built-in humidity sensor that allows you to monitor your home's humidity levels directly from the app or device display, it does not have the accessory terminals (ACC/HUM) required to actively control external equipment like humidifiers, dehumidifiers, or ventilators. However, we are working on developing a 7-relay version of the central HVAC thermostat that would support accessory control. Stay tuned for updates.

Yes, a C-wire (Common wire) is required to provide continuous power to the low-voltage Mysa for Central HVAC. If your system does not have a C-wire, a C-wire adapter is supported to ensure compatibility.

No. It's optional—for walls where your old thermostat left visible marks or a larger opening than the Mysa covers.

Over 55% of compatibility checker submissions need the adapter. Homes built before 2000 and hydronic heating systems are most common.

No. Mysa Smart Thermostat only.

Yes. Works with hot water boilers, hydronic in-floor heating, and zone valve configurations. For zoned systems, install the adapter at each zone valve—not at the boiler aquastat.

Yes. Mysa for Central HVAC is compatible with most 24V electric boiler and hydronic radiator systems. Since these systems often use a simple 2-wire setup, you will likely need to add our C-Wire Adapter. Verify compatibility using our online checker first.

No. The C-Wire Power Adapter works exclusively with Mysa for Central HVAC. Baseboard and in-floor thermostats use line voltage and don't require a C-wire.

Takes 15-20 minutes for most people. Connect five color-coded wires following the in-app guide, mount the base plate, attach the faceplate, power on and complete setup. Video instructions built into the Mysa app show every step. C-wire adapter comes pre-configured if you need it. Free installation support available by phone. Professional installation costs $75-150 if you prefer hiring an electrician or HVAC tech.

Mysa Central connects to your home's Wi-Fi network, allowing you to manage your HVAC system remotely. You can set schedules, adjust temperatures, and monitor energy usage through the Mysa app. This ensures your home is always at the perfect temperature when you need it.

✓ Works with gas furnaces, electric heat pumps, central air conditioning, and multi-stage systems

✓ Powered by C-wire (common wire)

✓ Multi-zone ready: group thermostats for synced control across your home

Yes. Mysa works with oil furnaces, but it requires a continuous power supply (C-wire). To install Mysa on a 2-wire system, you have two options:

1. Check for hidden wires
Many homes have a C-wire already installed but unused. Check behind your current thermostat for an extra wire tucked into the wall.

2. Install the Mysa C-Wire Power Extender kit
Mysa designed the thermostat and C-Wire extender kit in tandem to be the best thermostat for two-wire heat-only systems.

A specialized Mysa Trim Kit is coming soon (expected December–January). Designed to snap over your wall , it covers gaps and old screw holes left by larger legacy thermostats for a seamless look. No spackling or repainting required.

Yes. However, the adapter must be used with a separately purchased 24V power supply when being used with millivolt systems. 

Mobile App

Available on Apple App Store and Google Play

Integrations

Matter certified

Support for all major smart home platforms like Apple Homekit, Amazon Alexa, Google Home.

Security

IEEE 802.11 security (WFA, WPA/WPA2, WAPI)
Secure boot
TLS v1.2 w/2048 bit cert. keys
SHA-256 on crypto credentials
Level 1 CSA Cybersecurity Verification Program

Mysa for Central HVAC offers several benefits, including energy efficiency, remote access, and customizable scheduling. It helps reduce energy consumption, leading to lower utility bills while enhancing your comfort. Additionally, its sleek design complements any home decor.

White only.

Manual touchscreen controls always work for adjusting temperature and mode. System keeps heating or cooling your home normally. Smart features resume automatically when WiFi connection returns. Local settings stored in the thermostat survive power outages and network problems.

If you have any questions or need assistance, our customer support team is here to help. You can reach us via email or phone, and we strive to respond promptly. Additionally, our website offers a wealth of resources and troubleshooting guides.

Use the included Junction Box Adapter Plate for a secure mount. Fits single and double gang boxes. Add the Trim Plate on top for a finished look.

Use the Rext terminal with a standard 24 VAC plug-in transformer (sold separately at hardware stores, ~$15–20). This "T&T configuration" works for older boilers, standalone zone valves, and dry contact relay systems. One transformer can power up to three Mysa + adapter setups.

Mysa for Central HVAC is a smart thermostat designed specifically for central heating and cooling systems It allows you to control your home's heating and cooling from anywhere using your smartphone. With energy-saving features, Mysa Central helps you maintain comfort while reducing your energy bills.

Mysa costs $70-120 less than premium competitors while including the same core features. We are a privacy-focused Canadian company that never sells your data to Google or Amazon. You get energy monitoring as detailed as premium brands and Matter certification for future-proof smart home compatibility.

Buy the thermostat once and use every feature forever, because software updates remain free for the life of the device and we never lock features behind subscription paywalls.

There is a switch located on the back of the main display unit. If you have two separate R-wires (one labeled RH and one labeled RC), you must slide this switch to the opposite side of its default position. For single-transformer configurations (only one R-wire), ensure the switch remains in the default position.

Up to 17 cm x 17 cm (6.7" x 6.7")—large enough for most standard thermostat footprints.

Small flathead screwdriver and Phillips screwdriver.

You need a medium Phillips screwdriver.

We also recommend having these on hand:

• Small Phillips screwdriver
• Drill with 3/32" (hardwood) or 5/64" (softwood) bit
• Wire strippers
• Pliers

The adapter, wire connector for external transformer setups, adhesive mounting pad, wire label stickers, and installation guide.

Works with gas furnaces, electric heat pumps, central air conditioning, and multi-stage systems. Compatible with 95% of homes using standard 24V thermostats. Handles up to 3 stages of heating and 2 stages of cooling. Designed to work with the Mysa C-wire Power adapter (sold separately) for homes lacking common wire. Verify compatibility using our online checker or contact support with a photo of your current thermostat wiring.

No. Designed exclusively for Mysa Smart Thermostat.