Honeywell Home (Resideo)
Honeywell Home evohome Base Pack (ATP921R3100)
- Cloud integration
- Cloud required
- Wi-Fi
Prices verified September 2026
See more thermostats & heating picks on our Amazon storefront →Our verdict
Still the gold standard for true 12-zone UK heating, and the built-in evohome integration is actively maintained. But the £246 Base Pack is just the controller, relay box, stand and power supply — no TRVs included. Each extra zone needs an HR92 wireless radiator head at roughly £84, so a 4-5 zone house easily doubles the kit cost before fitting. It also needs a heating engineer to wire the relay box into the boiler and zone valves, not a weekend DIY job. Skip it for a flat or single-zone terrace; evohome earns its price on larger homes needing genuine per-room scheduling across 8-12 zones.
What can Home Assistant control on the Honeywell Home evohome Base Pack (ATP921R3100)?
| Control | Type | What it does |
|---|---|---|
| Zone climate (up to 12) | Climate entity per zone | Target temperature per room |
| System mode | Service call (evohome.set_system_mode) | Whole-house mode such as Auto or Away — the standard preset service doesn't reliably work here |
| Hot water | Water heater entity | On/off control for domestic hot water, if fitted |
The system's climate entity for the controller itself has no real setpoint — HA fabricates one as the average of every zone's temperature, so don't automate off it directly. A confirmed open bug means once you set a non-default preset (e.g. Away) there's no way back to normal scheduling through the standard preset service — you have to call evohome.set_system_mode instead, which is also the entity worth automating: trigger a whole-house AutoWithEco setback across all 12 zones at once when the last person leaves, something only meaningful because evohome's controller genuinely governs every zone together.
Specs
| installation | Wiring the relay box to the boiler and zone valves needs a qualified heating engineer — not a DIY install |
|---|---|
| zones supported | Up to 12 heating zones plus domestic hot water |
| trv battery life | Up to 2 years per HR92 head (2x AA) |
| hot water control | Supported via the BDR91 relay, using an optional hot water kit for a dedicated DHW zone |
| trv compatibility | Honeywell Home HR92 wireless radiator controller heads, ~£84 each; multi-head zoning kits (4 or 8 HR92s) sold separately, e.g. Plumbing Superstore's EVOPACK5 bundle |
| wireless protocol | 868MHz two-way RF between controller, relay box and HR92 heads — proprietary Honeywell Home protocol, not Zigbee/Z-Wave |
| base pack contents | ATC928G3000 Wi-Fi controller, table stand, power lead, BDR91 wireless relay box — no TRV heads included |
| base pack price gbp | 246 |
How does the Honeywell Home evohome Base Pack (ATP921R3100) compare?
| Product | From | Protocol | Local control | Integration |
|---|---|---|---|---|
| Honeywell Home evohome Base Pack (ATP921R3100) (this product) | £246 | Wi-Fi | Cloud | Cloud |
| Aqara Floor Heating Thermostat W500 | £69.98 | Matter, Thread, Zigbee | Yes | Native |
| Aqara Radiator Thermostat E1 | £54.98 | Zigbee | Yes | Zigbee2MQTT / ZHA |
| Aqara Radiator Thermostat W600 | £49.99 | Matter, Thread, Zigbee | Yes | Native |
Frequently asked questions
- Does the Honeywell Home evohome Base Pack (ATP921R3100) work with Home Assistant locally?
- Partly. The Honeywell Home evohome Base Pack (ATP921R3100) connects to Home Assistant through the manufacturer's cloud integration (evohome), which relies on the Honeywell Home (Resideo) cloud. It works in Home Assistant, but commands go via the internet and stop working during an outage of your connection or the Honeywell Home (Resideo) service.
- Which protocol does the Honeywell Home evohome Base Pack (ATP921R3100) use, and do I need a hub?
- The Honeywell Home evohome Base Pack (ATP921R3100) uses Wi-Fi. To pair it with Home Assistant you need no hub — it joins your Wi-Fi network directly. Honeywell Home (Resideo)'s own hub is not required when you integrate through the manufacturer's cloud integration (evohome).
- How much does the Honeywell Home evohome Base Pack (ATP921R3100) cost in the UK?
- The lowest price we have listed for the Honeywell Home evohome Base Pack (ATP921R3100) is £246 at Plumbing Superstore. Prices were last checked in September 2026 and change often, so confirm on the retailer's page before buying.
Honeywell Home (Resideo)
Honeywell Home evohome Base Pack (ATP921R3100)
£246 at Plumbing Superstore