Smart Multi-Zone Hydronic Control Solution

Overview

Deliver whole-building App connectivity without deploying WiFi thermostats in every room. Reduce hardware costs, simplify commissioning, and maintain the reliability of a wired hydronic control system.

Modern residential projects increasingly require smart zoning and App-based control as standard features. Conventional solutions often rely on installing a WiFi thermostat in every room, increasing hardware investment, network dependency, and commissioning complexity.

This solution eliminates the need for multiple WiFi endpoints through a shared-connectivity architecture. Built around the SAS931WCH Multi-Zone Control Kit and SA95 thermal actuators, the system combines a WiFi-enabled Master thermostat, BUS-connected Slave thermostats, and a low-voltage PLC communication network into a unified zoning platform.

The result is a scalable multi-zone hydronic control solution that delivers whole-building App access, automatic heating/cooling synchronization, and dependable wired communication while significantly reducing deployment costs and installation effort.

Core Capabilities

● Single-Master WiFi Connectivity
● Low-Voltage PLC BUS Communication
● Up to 8 Thermostats & 12 Thermal Actuators
● Automatic Heat/Cool Synchronization
● Heat Pump & Boiler Interlocking
● Polar-Free Installation

Solution Architecture

A low-voltage PLC BUS architecture that separates network connectivity from zone control, enabling reliable multi-zone synchronization through a single WiFi access point.

Key Project Metrics	Saswell BUS-Based Solution	Conventional Wired Setup	Full-WiFi Network
App Control Capability	✓ Whole-Building Access	✗ No Remote Access	✓ Individual Zone Access
WiFi Thermostats Required	1 (Master)	0	Up to 8
Network Configuration Load	1 Connected Device	N/A	Multiple Connected Devices
Commissioning Effort	Low	Medium	High
Heat/Cool Changeover	✓ Automatic System-Wide Sync	✗ Manual Adjustment	Usually Manual Configuration
Installation Complexity	Low (Polar-Free BUS)	Medium	High
Communication Reliability	High (Wired PLC BUS)	High	Dependent on RF Conditions
Hardware Investment	Optimized	Lowest	Highest

Architecture Advantage

The solution combines the SAS931WCH Multi-Zone Control Kit with SA95 thermal actuators to create a fully integrated hydronic zoning platform.

A single WiFi-enabled Master thermostat provides App connectivity for the entire system, while BUS-connected Slave thermostats maintain independent room-level control. Communication is carried over a low-voltage powerline carrier (PLC) signal on a polar-free 2-wire BUS, ensuring reliable operation while simplifying installation.

When a heating/cooling changeover is initiated by either the Master thermostat or a reversible heat pump, synchronization commands are automatically propagated across all connected zones. The wiring centre coordinates actuator operation to maintain consistent system-wide behavior throughout the building.

The result is lower hardware investment, simplified commissioning, reduced network dependency, and a more reliable user experience.

Application Scenarios

Designed for residential hydronic projects where smart connectivity, simplified commissioning, and reliable multi-zone control are essential.

Modern Residential Developments – Cost-Optimized Smart Zoning

Challenge: Today's homebuyers increasingly expect App-based heating control as a standard feature. However, equipping every room with an individual WiFi thermostat significantly increases hardware costs, network complexity, and commissioning time.

Our solution: The SAS931WCH architecture enables up to eight zones to share a single WiFi connection through a Master/Slave BUS network. By eliminating the need for multiple WiFi thermostats, developers and installers can deliver full-home smart control while maintaining the cost profile and reliability of a wired system.

● Single-Master WiFi Architecture
● Whole-Building App Connectivity
● Reduced Hardware and Commissioning Costs

Modern residential hydronic multi-zone control with single master WiFi thermostat

Reversible Heat Pump Systems
Automatic Heating/Cooling Synchronization

Challenge: In reversible heat pump systems, all room controllers must operate under the same heating or cooling logic. Manual seasonal changeovers can lead to inconsistent settings, comfort issues, and unnecessary service calls.

Our solution: The system receives heating/cooling changeover commands either from the Master thermostat or directly from the heat pump. The new operating mode is automatically synchronized across all connected zones via the PLC BUS network, ensuring consistent system behavior throughout the building.

● Automatic System-Wide Heat/Cool Synchronization
● Heat Pump Interlock Integration
● Real-Time BUS-Based Mode Propagation

Reversible heat pump multi-zone hydronic control with automatic heat cool sync

Need a cable-free zoning solution?

Explore our WHL Series Multi-Zone RF Solution for retrofit projects and installations where running control wiring is impractical.

Explore Wireless Multi-Zone Solutions

Advantages

Shared WiFi Connectivity

Provide App access for the entire building through a single WiFi-enabled thermostat, eliminating the need for multiple connected devices.
Lower Hardware Investment

Reduce smart zoning deployment costs by replacing multiple WiFi thermostats with BUS-connected room controllers.
Simplified Commissioning

Minimize network configuration and device provisioning effort through centralized connectivity and automatic synchronization.
Reliable Wired Communication

Utilize low-voltage PLC BUS communication to maintain stable control performance without RF signal limitations.
Automatic Seasonal Changeover

Synchronize heating and cooling operation across all zones automatically, reducing user intervention and service requirements.
Flexible Multi-Zone Expansion

Support up to eight thermostats and twelve thermal actuators for a wide range of residential hydronic zoning layouts.

Related Products

Multi-Zone Control Kit

SAS931WCH

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Hydronic Thermostat

Power supply and signal input: DC12 ~ 18V carrier non-polarity input
(power supply wiring control centre, maximum current 100mA)

Storage environment temperature and humidity: -10 ~ 60°C, 0 ~ 90% RH (non-condensing)

Working environment temperature and humidity: 0 ~ 50°C, 0 ~ 80% RH (non-condensing)

Temperature display range: 0 ~ 50°C

Display accuracy: 0.1°C

Size: 86x86x13mm

Protection level: IP21

WIFI antenna emission frequency(master controller): 2.4GMHz

WIFI wireless transmission distance(master controller): 60M in the open area

Wiring control centre

Power source: 100-240VAC 50 / 60Hz (maximum current 10A)

Storage environment temperature and humidity: -10 ~ 60°C, 0 ~ 90% RH (non-condensing)

Working environment temperature and humidity: 0 ~ 50 °C, 0 ~ 80% RH (non-condensing)

Size: 298 X 88 X 66mm

IP rating: IP40

Thermal Actuators

SA95

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● Power supply: SA905-T(220V):100-240VAC; SA905-T(24V):24VAC

● Power consumption: ≤2W

● Stroke: 4.5mm

● Force: 80N~130N

● Ambient temperature: 0 ~ +50°C

● Ambient humidity: 10%~90%,non-condensing

● Protective housing: IP 54

● Valve interface: M30x1.5mm

● Temperature sensor: NTC 100K, clip for pipe outer diameter from 12~20mm

● Fluid temperature:10~60°C(Flow temperature limitation is active when lever is closed )

Get in Touch

Contact our friendly customer service team for any questions, concerns, or suggestions. We'd love to hear from you.

Headquarters Hotline: +86 755 61218391 Headquarters Hotline +86 755 61218391

Headquarters Email: info@saswell.com

MENA Tech Support Hotline: +97155 6743682

MENA Tech Support Email: support@saswell.com