Complete Guide to Heatmiser Thermostats for Water Underfloor Heating in 2026

Water underfloor heating has a knack for feeling effortless once it is running well, but the comfort you feel is really the result of good control. The thermostat decides when each room calls for heat, the wiring centre translates those calls into actuator movement at the manifold, and your heat source only fires when demand is genuine. Get that chain right and the system feels quiet, even, and predictable.

This guide focuses on Heatmiser thermostat 2026 choices for wet underfloor heating, with practical notes for homeowners who want confidence and trade professionals who want fewer callbacks. The goal is simple: clear, reliable water underfloor heating control with smart zoning where it makes sense.

A quick orientation: water underfloor heating is normally split into zones, each zone has at least 1 actuator on the manifold, and each zone benefits from its own thermostat and schedule.

Why zoning matters so much with wet UFH

A wet floor circuit responds slowly because the slab or screed stores heat, that thermal mass is a feature because it levels out temperatures and supports lower flow temperatures. The control strategy should respect that pace.

Zoning earns its keep when different rooms have different patterns. Bedrooms, offices, open plan kitchens, extensions, and bathrooms rarely want the same temperatures at the same times. A multi zone setup lets you run smart heating zones that match reality, so rooms only take heat when they need it.

Industry research and user reports frequently point to meaningful savings when smart zoning and scheduling replace a single whole house timer, figures in the region of 10 to 18 percent are often quoted for smart controls with zoning and adaptive scheduling. Real world results depend on insulation, setpoints, occupancy patterns, and heat source efficiency, yet the direction is consistent. Better control tends to reduce waste.

Heatmiser Neo thermostats: what you get in 2026

Heatmiser's Neo ecosystem is built around a simple idea. Each room thermostat manages its zone locally, while the system can be unified in an app when a NeoHub is added. That structure suits wet UFH because each room can follow its own schedule without turning the rest of the house into a compromise.

Core strengths installers and homeowners care about

App based control with central coordination works well when you want quick changes without walking to the wall plate. Pair compatible thermostats with a NeoHub and you can manage multiple zones from one place, including setpoints, schedules, and away modes.

Scalable multi zone control is a standout, a single hub is commonly specified for up to 32 zones, which covers most domestic and many light commercial projects without awkward workarounds.

Sensor options for floor heating matter with wet UFH in bathrooms and timber or vinyl floors where floor temperature limits protect the finish. Models that support remote air and floor sensors allow air comfort control while still obeying a safe floor limit.

Which Neo thermostat type is best for wet UFH

Advanced smart thermostat configurations can feel like a maze, so it helps to anchor the decision on wiring and control method.

• neoStat (wired) tends to suit new installations where a cable run to each thermostat is planned, or refurbishments where wiring routes are straightforward.
• neoAir (wireless) is popular when wall chasing is not desired, or when layout changes are likely and you want flexibility.
• neoHub is the piece that ties everything into app control and multi zone management, it is also the route to remote access.

The neat part is that you can mix approaches within the same project, using wired stats where wiring is easy and wireless where it is awkward, while still presenting a single system to the homeowner.

The UH8 wiring centre: the practical heart of a wet UFH manifold

A wiring centre is where underfloor heating stops being theoretical and starts being dependable. In a typical manifold cabinet you have multiple actuators, a pump, sometimes a blending valve, and a link to the boiler or heat pump controls. The Heatmiser UH8 wiring centre brings those connections together so that each thermostat call for heat drives the right actuator and enables the right outputs.

What the UH8 does in plain language

• Takes calls for heat from up to 8 zones and switches the corresponding actuators outputs.
• Provides outputs for pump and valve control so circulation starts when any zone demands heat.
• Offers a volt free boiler enable connection, which is helpful when interfacing with different heat sources and control schemes.
• Supports timed channels that can be used for zone grouping or time control strategies, depending on your system design.

For many installers, the UH8 becomes the standard choice because it keeps wiring neat and repeatable, which reduces commissioning time and fault finding later.

UH8 vs UH8 RF: choosing the right wiring centre

The best comparison is not about better or worse, it is about how thermostats communicate.

• UH8 (hard wired) expects wired thermostats connected back to the wiring centre.
• UH8 RF is designed for wireless thermostats and uses radio communication to receive calls for heat.

If the project is a new build with easy cable routes, a wired UH8 often keeps things simple. If the project is a retrofit, listed building, or a home where décor must stay intact, UH8 vs UH8 RF usually comes down to whether wireless thermostats will save days of disruption.

A practical note from site experience: metal manifold cupboards can reduce RF range. Where a wireless wiring centre is mounted in a metal enclosure, using an external aerial option or relocating the receiver can save time chasing intermittent communication.

12 volt and 230 volt models: what compatibility really means for water circuits

Confusion around 12 volt and 230 volt thermostats is common because wet UFH systems can mix voltages. The critical principle is that thermostat supply voltage is not the same as actuator switching voltage.

A reliable way to think about it

• 230 volt thermostats are powered by mains and often switch a switched live output suitable for standard wiring centres.
• 12 volt thermostats are powered by low voltage and are often used where low voltage cabling already exists, especially for upgrade paths.

For wet UFH manifolds, actuators are commonly 230 volt thermal actuators, so the wiring centre typically handles the 230 volt switching to actuators, pumps, and valves.

Where the UH8-N fits

If you are working with Heatmiser's 12-volt thermostat network, the UH8-N wiring centre is designed specifically to integrate 12 volt thermostats while still controlling 230 volt actuators and outputs where needed. This can be a clean route when replacing legacy low voltage thermostats, because it preserves existing cabling while modernising the control layer.

Volt free contacts and heat source control

Many wet systems rely on volt free switching to enable a boiler, heat pump control input, or a zone valve. Heatmiser wiring centres commonly include volt free connections for this reason. For trade professionals, always confirm what the heat source expects at the enable terminals, because some appliances need a simple contact closure while others have specific control logic.

Installation tips and configuration basics for trade professionals

Wet UFH controls are forgiving on paper and unforgiving on site. Small wiring errors can mimic actuator faults, sensor issues, or comms dropouts. A methodical approach keeps commissioning calm.

Manifold and actuator wiring habits that save time

1. Label every zone loop and every thermostat cable before termination, especially where multi loop rooms exist.
2. Check actuator current and quantity per zone output, several wiring centres support multiple actuators per zone, but you still need to respect output ratings.
3. Keep separation between mains and low voltage conductors inside the wiring centre, it makes compliance and troubleshooting easier.
4. Confirm pump and valve outputs operate only on demand, then confirm any pump overrun or delay behaviour expected by the design.

Thermostat setup for wet UFH comfort

• Set appropriate switching differential and cycle behaviour for underfloor heating, rapid cycling defeats the benefit of thermal mass.
• Use floor sensors where the floor finish requires temperature limiting, set a sensible maximum floor temperature based on the manufacturer's recommendations.
• Configure schedules around occupancy and warm up time, a wet floor may need an earlier preheat for morning comfort, especially in colder rooms.

Neo system commissioning checks

• Pair the correct thermostat to the correct zone output, a simple mismatch can waste hours.
• Name zones clearly in the app, homeowners engage with systems that are easy to understand.
• Confirm remote access and hub connectivity before leaving site, Wi Fi placement and router settings often need small adjustments.

Recommended Heatmiser product choices you can source through ThermRite

ThermRite supplies a range of Heatmiser controls suited to wet UFH. For a typical 2026 specification, these combinations cover most homes.

• Heatmiser neoStat 12V paired with UH8 N where low voltage wiring already exists and a tidy upgrade path is required.
• Heatmiser UH8 for hard wired 230 volt zoning at the manifold, suited to new builds and major refurbishments.
• Heatmiser UH8 RF V2 where wireless thermostats are the right fit, often used in retrofits and finished homes.

When selecting, match the control method to the building fabric and the client's expectations. A flawless wireless system can be perfect, yet a hard wired system can feel bulletproof where cabling is already planned.

Bringing it all together: a simple selection checklist

• Choose Neo thermostats when multi room scheduling and app control matter, particularly where you want finer energy management.
• Choose UH8 vs UH8 RF based on wiring practicality and RF suitability at the manifold location.
• Decide 12 volt vs 230 volt by looking at existing cabling and the wiring centre model, not by guessing from actuator voltage.
• Commission for the slow response of wet UFH, stable schedules and correct sensor settings usually deliver the smoothest comfort.

Frequently Asked Questions

How many zones can a Heatmiser Neo system control in one property?

A Neo system with a hub is commonly specified for up to 32 zones, which is enough for most domestic projects with full room by room control.

What is the difference between UH8 vs UH8 RF for water underfloor heating control?

UH8 is for wired thermostats, UH8 RF receives wireless calls for heat from compatible RF thermostats, both switch actuators at the manifold and can provide pump and boiler enable outputs.

Can I use 12 volt thermostats with 230 volt underfloor heating actuators?

Yes, when the correct wiring centre is used. A 12 volt thermostat can signal a wiring centre such as UH8 N, which then switches 230 volt outputs to the actuators and system controls.

Do Neo thermostats work well with the slower response of wet UFH?

Yes, when configured sensibly. Optimised installation strategies that include stable schedules, appropriate temperature differentials, and floor sensor limits where required tend to produce the best comfort and efficiency.

What should installers check first when a zone does not heat up?

Start with basic demand and wiring checks. Confirm the thermostat is calling for heat, confirm the correct zone output is energised at the wiring centre, then verify the actuator head opens and the manifold flow is available.

Next steps

A well zoned control setup can make wet underfloor heating feel consistent and economical, and the right Heatmiser combination keeps installation and long term use straightforward. If you are planning a new manifold, upgrading old controls, or specifying a full smart zoning package for a property, speak with ThermRite to match thermostats, wiring centres, and zone strategy to your exact system, then commission it with confidence and leave the homeowner with controls they will actually enjoy using.