Project Overview
As Smart Heating specialists in Devon, we were called to a home in Totnes, Devon. The brief was clear: modernise an ageing electric underfloor heating system and make it fully controllable through the Heatmiser Neo smart platform.
The homeowner’s goals were ambitious but realistic. They wanted to retain their existing electric underfloor heating (UFH) system but make it safer, more efficient, and app-controllable. They also wanted to prepare the property for a more sustainable future, including solar PV, battery storage, and an air-source heat pump.
Over two days on site, we designed and installed a new Heatmiser Neo control system, replaced unsafe wiring, and optimised the property’s electrical infrastructure for both safety and future upgrades.
As NICEIC Approved Contractors, we’ve seen our fair share of complex heating and control challenges. But this project really highlights how Heatmiser Neo controls can transform a dated system into a modern, smart, and energy-efficient solution.
Read on or what the video below.
Initial Assessment
When I arrived, it was immediately clear that the property had evolved over time — new circuits had been added, old ones modified, and a lot of “temporary” fixes had become permanent.
The home operated on an Economy 7 tariff, running the electric UFH between midnight and 7 a.m., and the load was spread across two active phases. Unfortunately, much of the wiring was outdated, with a few concerning discoveries: earth conductors being used as live wires, consumer units without proper overload protection, and an annex supply cable running far beyond its intended limits.
The system also had multiple distribution boards. One for the main house and another dedicated to the pottery equipment and underfloor heating mats. Wireless connectivity was patchy thanks to thick stone walls, and the existing thermostats couldn’t handle the load of the UFH circuits safely.
A direct replacement of the thermostats would have been unsafe, so we needed to rethink the entire approach.
Challenge of Integrating Heatmiser Neo Controls
This was a particularly intricate job for a domestic property. The home’s electrical setup was already operating near capacity, regularly drawing over 70 amps during normal use. When factoring in the electric showers, immersion heater, pottery kiln, and underfloor heating, total demand could exceed 100 amps.
This high load explained the two-phase arrangement, but it also meant the existing consumer units were stretched to their limits. To prepare the home for renewables, we needed to consider a three-phase upgrade to balance future loads from solar inverters, EV chargers, and an air-source heat pump.
From a controls perspective, we were dealing with:
- Aged, unsafe wiring that wasn’t fit for purpose.
- Electric UFH mats on high-load circuits that standard thermostats couldn’t handle.
- Patchy Wi-Fi and poor signal penetration due to thick stone walls.
- An outdated control strategy that couldn’t take advantage of off-peak tariffs effectively.
The challenge was to integrate Heatmiser Neo controls. We always aim to word discreetly, safely and intelligently while modernising the property’s heating without having to rewire every circuit.
Electrical Assessment & Load Testing
Before making any recommendations, we carried out detailed load testing. This confirmed that even under moderate use, the home’s electrical demand was far higher than expected.
Once we factored in the planned future installations — a 9 kW solar inverter, 20 kWh battery storage, a 40-amp EV charger, and a 25-amp air-source heat pump — it was obvious that a three-phase supply would be essential down the line.
In the short term, our focus was to make the system safe and efficient, while ensuring the groundwork was in place for the upcoming renewable upgrades.
Smart System Design
Given the unsafe and outdated wiring, a direct rewire of the entire system wasn’t practical. Instead, we designed a Heatmiser Neo smart control system that used wireless communication and contactor-controlled UFH circuits to eliminate the need for traditional thermostat wiring.
The new setup featured:
- Heatmiser Neo Air V3 thermostats for the two main underfloor heating zones.
- RF receivers wired into heavy-duty contactors, safely handling high electrical loads.
- A Heatmiser Neo-stat E for immersion heater control.
- A Neo Hub 2 connected to the home router for full smart control via the Heatmiser Neo App.
- Two RF Booster Plugs strategically positioned to extend the wireless range through the property’s thick stone walls.
This configuration offered the perfect balance of safety, control, and efficiency giving the homeowner app-based management without rewiring the house.
See how we integrate similar systems on our Smart Home Heating & Cooling page.
Installation & Commissioning
We began by safely removing the old thermostat cabling and isolating unsafe connections. New RF receivers were installed to control the existing contactors, and we replaced the faulty immersion thermostat, which had been operating inconsistently. It might seem like small thing, but it’s a critical fix.
The Neo Air V3 thermostats were mounted on stylish desktop stands, allowing the homeowner to move them if needed for optimal temperature sensing. The Neo Hub was connected directly to the router, ensuring stable connectivity, while the booster plugs were placed to guarantee reliable signal coverage throughout the house.
Once all components were installed, we programmed the system to make the most of the Economy 7 tariff. The underfloor heating circuits were scheduled between midnight and 6 a.m. to take advantage of off-peak electricity, while the immersion heater ran several short bursts during the day to complement the property’s solar thermal system.
Manual override remained available on all zones, providing flexibility alongside automation.
Future-Proofing the Property
While the immediate focus was on safety and smart control, this project also laid the foundation for the client’s long-term sustainability goals.
We provided detailed recommendations to help future-proof the electrical system:
- Upgrading to a full three-phase supply for load balancing and expansion.
- Replacing existing consumer units with a modern three-phase distribution panel.
- Coordinating with the energy supplier to install a new three-phase meter.
- Reserving space for future battery storage, EV charging, and inverter systems.
Results
The transformation was remarkable. The homeowner now enjoys:
- App-controlled underfloor heating and immersion systems via the Heatmiser Neo app.
- Wireless operation that eliminated unsafe wiring and avoided invasive redecoration.
- Optimised off-peak scheduling, reducing running costs while maintaining comfort.
- Reliable signal coverage throughout the property thanks to booster plug placement.
- A future-ready electrical setup capable of supporting solar, battery, and EV technology.
For a two-day installation, the results were impressive. We managed to achieve a complete shift from a dated, inefficient system to a modern, connected, and intelligent home heating solution.
Why Choose Heatmiser Neo Controls
The Heatmiser Neo system is an incredibly versatile platform that bridges the gap between traditional heating and full smart-home automation. In this case, it provided the perfect solution for modernising an existing electric UFH system without the disruption of rewiring.
By combining wireless thermostats, contactor-based safety control, and app-based management, the homeowner now has a system that’s efficient, intuitive, and ready for renewable integration.
This project perfectly demonstrates what we specialise in at Heritage Electrical Automation. We love nothing more than transforming outdated, inefficient systems into safe, intelligent, and sustainable smart home environments.
