# Check if Halo works with your system

> Halo works with most 24 V heating and cooling systems, including heat pumps. Check your wires before you buy.

Source: https://helpdox.fekbd.com/docs/halo-thermostat/setup/check-if-halo-works-with-your-system/

Halo works with most 24 V heating and cooling systems, including heat pumps. Check your wires before you buy. Follow the steps below — it takes just a few minutes.

## Before you begin

- A Phillips screwdriver and the Halo app
- Power to your heating system switched off at the breaker

## Steps

1. 1Turn off powerSwitch off your heating system at the breaker.
2. 2Look at the wiresRemove your old thermostat’s cover and note the letters next to each wire.
3. 3Use the checkerEnter the letters in the Halo app’s compatibility checker.

Tip

Thick wires or 120 V/240 V labels mean a line-voltage system — Halo is not compatible.

## Still stuck?

Have your serial number ready (Settings → About on the thermostat, or the label on the back plate).