steamloop 1.1.0

Local control for choochoo based thermostats

steamloop

---

Async Python library for local control of thermostat devices over mTLS (port 7878).

Installation

pip install steamloop

CLI

Pairing

Put the thermostat in pairing mode (Menu > Settings > Remote Access > Pair New Device), then:

steamloop 192.168.1.100 --pair

This saves a pairing file in the current directory with the secret key.

Monitoring

steamloop 192.168.1.100

Interactive commands: status, heat <temp>, cool <temp>, mode <off|auto|cool|heat>, fan <auto|on|circulate>, eheat <on|off>, help.

Library Usage

import asyncio
from steamloop import ThermostatConnection, ZoneMode, FanMode

async def main():
    conn = ThermostatConnection(
        "192.168.1.100",
        secret_key="your-secret-key-from-pairing",
    )
    async with conn:
        # State is populated automatically from thermostat events
        for zone_id, zone in conn.state.zones.items():
            print(f"{zone.name}: {zone.indoor_temperature}°F")

        # Send commands (sync — no await needed)
        conn.set_temperature_setpoint("1", heat_setpoint="72")
        conn.set_zone_mode("1", ZoneMode.COOL)
        conn.set_fan_mode(FanMode.AUTO)

asyncio.run(main())

Pairing Programmatically

pair() returns the secret key directly — store it however you like:

from steamloop import ThermostatConnection

async def pair(ip: str) -> str:
    conn = ThermostatConnection(ip, secret_key="")
    try:
        await conn.connect()
        ssk = await conn.pair()
        return ssk["secret_key"]  # store in a database, config entry, etc.
    finally:
        await conn.disconnect()

Or use the built-in file helpers to save/load pairing data to disk:

from steamloop import ThermostatConnection, save_pairing, load_pairing

# Save after pairing
await save_pairing(ip, {
    "secret_key": secret_key,
    "device_type": "automation",
    "device_id": "module",
})

# Load later
pairing = await load_pairing(ip)
conn = ThermostatConnection(ip, secret_key=pairing["secret_key"])

Event Callbacks

def on_event(msg):
    print("Received:", msg)

remove = conn.add_event_callback(on_event)
# later: remove() to unregister

Home Assistant Integration

Key design points for using steamloop in a Home Assistant integration:

• Commands are sync — set_zone_mode(), set_fan_mode(), set_temperature_setpoint() use transport.write() internally, so they won't block the event loop. No await needed.
• State is always fresh — the asyncio.Protocol receives events via data_received() and updates conn.state automatically. Just read properties directly.
• Auto-reconnect — after calling start_background_tasks(), the connection automatically reconnects with exponential backoff (5s, 10s, 20s, ... up to 5 min).
• Event callbacks — use add_event_callback() to trigger async_write_ha_state() when the thermostat pushes updates.
• Multi-zone — create one ClimateEntity per conn.state.zones entry. Zones are populated automatically after login.

API Reference

ThermostatConnection(ip, port=7878, *, secret_key, cert_set=None, device_type="automation", device_id="module")

Method	Async	Description
connect()	yes	Establish mTLS connection
login()	yes	Authenticate with secret key
pair()	yes	Pair and receive secret key
start_background_tasks()	no	Start heartbeat + auto-reconnect
disconnect()	yes	Close connection and stop tasks
set_temperature_setpoint(zone_id, *, heat_setpoint, cool_setpoint, hold_type)	no	Set zone temperature
set_zone_mode(zone_id, mode)	no	Set zone HVAC mode
set_fan_mode(mode)	no	Set fan mode
set_emergency_heat(enabled)	no	Toggle emergency heat
add_event_callback(fn)	no	Register event listener (returns unregister callable)

Supports async with for automatic connect/login/disconnect:

async with ThermostatConnection(ip, secret_key=key) as conn:
    ...  # connected, logged in, background tasks running
# automatically disconnected

Enums

• ZoneMode — OFF, AUTO, COOL, HEAT
• FanMode — AUTO, ALWAYS_ON, CIRCULATE
• HoldType — UNDEFINED, MANUAL, SCHEDULE, HOLD

State

• conn.state.zones — dict[str, Zone] with temperature, setpoints, mode per zone
• conn.state.fan_mode — current FanMode
• conn.state.supported_modes — list[ZoneMode]
• conn.state.emergency_heat / relative_humidity / cooling_active / heating_active

Contributors

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!

Credits

This package was created with Copier and the browniebroke/pypackage-template project template.