Green Mountain Grills for Home Assistant

Control and monitor a Green Mountain Grills Wi-Fi pellet grill from Home Assistant, over your own network. No cloud account, no vendor API, no internet needed after setup - just delicious data.

The code that talks to the grill over the network lives in gmg-local, a standalone library; this repository is the Home Assistant integration.

Features

• Full climate control from Home Assistant. The pit and both probes are climate entities - set the pit temperature and probe done-targets from any dashboard or automation. Every change is read back and verified, so the dial only ever shows a target the grill actually accepted.
• The whole cook, on the record. Temperatures, fire state, ignition progress, warnings, and power state land in the recorder every 10 seconds while the grill is on - every cook becomes a chart in your Home Assistant history.
• Automate the smoke. Everything is an entity: text yourself when the ribs hit 195 °F, when the fire state turns Running, or when the grill raises a warning.
• Watch ignition happen. The fire state progress sensor tracks the grill establishing its fire in real time - the whole sequence is documented in The 0-1-2-3 startup cycle.
• Local and self-sufficient. Discovered by UDP broadcast on your LAN (or direct IP across VLANs). No account to create; works when the internet doesn't.

Engineering

• Full-width decoding: the grill sends each temperature as two bytes; reading only one truncates the value and wraps every reading above 255 - a 350 °F pit reads as 94 °F. Both bytes are read, verified against a real grill.
• Request coalescing: the grill answers one client at a time, so the twelve entities never poll it separately - every update coalesces into one shared request per cycle.
• Strict parsing: a status reply parses whole or not at all. A healthy reply is 52 bytes; anything shorter is retried, never parsed - so no field is ever invented.
• Read-back verification: every change is read back from the grill and compared - the dial never shows a number the grill didn't actually accept.
• Adaptive polling: about every 10 seconds while the grill is on, every 60 while it's off - responsive during a cook, quiet overnight.
• No sentinel values: an unplugged probe reads unknown, not 607 °F - the grill's in-band placeholder for "nothing connected."

Requirements

• A Green Mountain Grills Wi-Fi pellet grill on your network - one per Home Assistant, as the integration is single-instance. Developed against a Jim Bowie model; the protocol references credited below cover GMG's other Wi-Fi models.
• Home Assistant 2026.5+.
• UDP port 8080 allowed between Home Assistant and the grill - the port the grill listens on. Only a concern across VLANs or firewalls; on a typical home network with no VLANs there is nothing to configure.
• PyPI reachable on first start after installing or upgrading - the gmg-local dependency installs automatically.

Install

Two ways - pick one:

• HACS (custom repository): HACS → Integrations → ⋮ → Custom repositories → add https://github.com/y3klab/gmg-ha as an Integration → install → restart Home Assistant.
• Manual: copy custom_components/gmg/ into your config/custom_components/ and restart.

Don't do both: Home Assistant loads the hand-placed copy instead of the HACS one, and HACS updates stop taking effect.

Then Settings → Devices & Services → Add Integration → Green Mountain Grills. It discovers by UDP broadcast; if the grill is on a different VLAN, supply its IP address and the integration will contact it directly.

Entities

12 for a grill with two probes, all served by one shared poller:

entity	type	what it holds
Grill	climate	the pit: current temperature and its target
Probe 1 / Probe 2	climate	the meat probes: current temperature and a done-target
Temperature	sensor	pit temperature on its own, for easy graphing
Probe 1 temperature / Probe 2 temperature	sensor	probe readings; unknown when unplugged
Fire state	sensor	Off / Startup / Running / Cool Down / Fail
Fire state progress	sensor	how established the fire is: 0 → 100 in 25% steps as it lights, reaching 100 when the pit reaches 150 °F - the moment the fire state turns Running - then descending through Cool Down. Not the 0-1-2-3 count the grill's panel shows during startup, and not a pellet level
Power state	sensor	Off / On / Fan (Fan is the cool-down blower)
Warning	sensor	the grill's own warning report
Probe 1 connection / Probe 2 connection	binary_sensor	whether a probe is physically plugged in

Credits

Inspired by @jwhitby91's gmg_home_assistant integration, which powered my GMG+HA dashboard for years. 🙏 This integration is a from-scratch rewrite, with the protocol in gmg-local.

Protocol reference cross-checked against brandenco/green-mountain-grill (Go) and gmg on PyPI by Christopher McKay.

Thanks also to the GMG Support team, who took the time to answer one owner's unusually detailed questions about what the grill is doing and when.

Cooked up by the JoPº GRILL+CODE team - part of the Y3K Lab brand family.

License

MIT - see LICENSE. The JoPº logo is original artwork and is not covered by the MIT license.

Not affiliated with or endorsed by Green Mountain Grills.