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Smart Home / IoT
·2025

Smart heating system commissioning.

The complete system now works as intended. All 15 underfloor heating circuits across 5 zones respond independently. All 4 radiators are controllable per-room. The Vaillant boiler starts and stops on demand via OpenTherm. The homeowner controls everything from the Evohome panel or the Total Connect Comfort app on their phone. Full system documentation was handed over.

Client
Residential homeowner via general contractor
Scale
15 heating circuits · 5 zones · 4 radiators
Duration
One day on-site
Year
2025
The situation

A fully installed system that didn't work

A homeowner had just completed a full renovation. The heating contractor had installed a Honeywell Evohome smart heating system — hub, underfloor heating module, wireless thermostats, radiator actuators, and a Vaillant boiler — but couldn't get it all talking together. We were brought in by the general contractor — who manages all tasks and subcontractors for the project — despite having zero prior experience with heating systems. What we do have is the ability to read documentation, reason through a system, and not give up.

What we did

Systematic commissioning from the ground up

We started fresh: reading the commissioning docs for every device, understanding the 868 MHz RF network topology, and pairing each component to the Evohome hub in the correct sequence.

HCC100 underfloor heating module configured via Resideo Pro app and paired to Evohome — 15 circuits across 5 zones (kitchen, living room, halls, bathroom)
5× DT4R wireless thermostats paired and mapped to their respective zones
4× HR92 radiator actuators paired to the correct rooms (guest room, PA room, study, master bedroom)
Traced the boiler wiring — R9 relay correctly connected to the Vaillant's OpenTherm subboard
Diagnosed the actual fault: the boiler needed a protocol reset to recognise OpenTherm after connection
Full end-to-end functional test: each zone raised, underfloor valves opened, radiators responded, boiler fired on demand
The result

Fully operational, fully remote

The complete system now works as intended. All 15 underfloor heating circuits across 5 zones respond independently. All 4 radiators are controllable per-room. The Vaillant boiler starts and stops on demand via OpenTherm. The homeowner controls everything from the Evohome panel or the Total Connect Comfort app on their phone. Full system documentation was handed over.

Tech & tools
Honeywell EvohomeHoneywell HCC100Honeywell DT4RHoneywell HR92Resideo R9VaillantOpenTherm868 MHz RFTotal Connect Comfort