Under-Floor Heating (Water)
Under-Floor Heating is becoming much more common in new homes as it is a great way to heat large or open spaces - it also provides a nice convenient heating system that's always warm on your toes.
The system uses a central boiler to heat the water, a pump then circulates this through long pipe runs that are positioned just below the floor's surface. The water flow is controlled by an Actuator valve.
The majority of Under-Floor Heating (UFH) systems have multiple zones, so the water is pumped through a central Manifold which distributes the water to the various zones. The manifold also houses the electrically-operated Actuator Valves that control the water to each zone. When the actuator is turned On, water flows to that zone. When it is Off, no water flows to that zone. Importantly the system also monitors when no heat is required or when all zones are off - if this is the case, it shuts down the boiler and maintains the Boiler Interlock.
This guide extends how a multi-zoned Under-Floor Heating system can be easily creating using Z-Wave heating products.
Add Home Automation to Your Under-Floor Heating
Most UFH systems are relatively self-contained - the actuators, thermostats, and control system work together to run the system smoothly and efficiently. But you may want to control the system remotely (from your smartphone) or as part of a wider system that runs your home's lights, multimedia, security - and that's where Home Automation comes in.Using home automation you can add as little or as much control to your UFH system as you wish, and if you are just implementing you system, you can use Z-Wave home automation to run the entire system.
How it Works
The boiler control and actuators are kept the same as in the original system. Z-Wave Relays (Switches) are added to control each Actuator Valve, this allows each Actuator valve to be controlled wirelessly by the Z-Wave system. Each heating zone has a Z-Wave thermostat that controls the temperature of that zone by monitoring the zone's temperature and turning the actuator valve On or Off to control the flow of hot-water into that zone.
The Z-Wave controller will run a Schedule 'Scene' that determines when each zone should be active and at what temperature. It will also monitor the zone's temperature and determine if the actuator should be On or Off. This enables the system to run itself automatically, but you can over-ride it even if you are away from home, stuff in traffic on a dark December night.
After you've decided how you'd like the system to behave, you should take note of some important points - some are required by current Building Regulations.
Don't forget about the Boiler Interlock!
The heating system must be able to turn off the boiler when no heat is required. For example, if all the zones are off, as they have reached temperature, then the boiler must be switched off to avoid wasting energy. Otherwise the boiler would continue to heat water and send it around the system (but not through the zones). This would continue until the room temperatures reduced or the heating system was turned off.
The Boiler Interlock is required by Building Regulations.
Hot Water Flow
The flow of hot water is controlled by the Manifold and Actuator valves. The Z-Wave system needs to be able to control the actuator valves in order to control the heating system efficiently.
For Multi-Zone systems, creating 'Scene' and control 'algorithms' can become complicated very quickly, so you need to plan your system before you start implementing it. You should plan how the 'Scene' logic will actually control the system - making sure that each zone can control the boiler and that the boiler will be turned off when no heat is required by any zones.
All Z-Wave Controllers will be able to run this type of control logic, but few of them will be able to do it using their standard scene editors. Most people use LUA scripting to control more complex multi-zone heating systems. Before going too far, it's worth researching examples of how this is done - so you can decide if it is something you're capable of developing for your own system.
Components - what they do
Whichever type of Multi-Zone system you decide to implement, they both use the same Z-Wave devices.
These control the Actuator Valves, ensuring that you can control the water flow to each zone of the UFH heating system.
- Fibaro Switch 2 (Double)
Dual relay that can control two Actuator Valves and therefore two zones.
Communicates directly with the Boiler Receiver or Relay to control the boiler (heating) depending on the room's ambient temperature and the 'set-point' temperature you've selected. This allows the system to run the heating system with the optimum efficiency as the thermostat has in-built heating algorithms that optimise the boiler On/Off periods. You can change the thermostat's set-point temperature wirelessly, giving you complete control over your heating system. More Details - Basic Boiler Radiator system with Single Thermostat
- Secure Wall Thermostat (SRT321)
Wall mounted thermostat controls the boiler (via the receiver) and can have it's set-point changed by the Z-Wave controller. All heating schedules will be run in the Z-Wave controller and the heating's On/Off periods controlled by changing the wall thermostat's set-point.
- Secure Programmable 7-day Thermostat (SCS317)
Very similar to the Secure Wall Thermostat, except it has an integrated 7-day timer that enables it to run the heating based on schedules you program into the thermostat - it can have up to 6 temperature periods per day.
This Z-Wave Switch (Relay) enables you to control the boiler wirelessly. You may need this if you are implementing a new UFH system that does not have any boiler control via the Manifold and Actuator Valves.
- Secure Single-Channel Boiler Receiver
Purpose designed Z-Wave Receiver for controlling a Combi boiler. It enables the Z-Wave system to control the boiler and has buttons and LEDs for manual On/Off control.
Temperature Sensors and more...
Can be used as an alternative to Wall Thermostats or as an extra 'independent' sensor to monitor the temperature of different parts of the house. For example, your Wall Thermostat may be positioned near the light switch, but may not be the best place to measure the room temperature - perhaps next to the sofa is more appropriate. Adding additional Temperature sensors allows you to fine tune the heating to suit the use of the room - perhaps you could create an averaged Temperature reading between the Wall Thermostat and the additional sensor and control the system based on that.
- Secure Wall Temperature Sensor
Wall mounted temperature sensor can report the room's temperature to the 'Scene' running the heating control.
- Fibaro Door/Window Sensor (Gen5) with Temp Sensor
Flexible Door/Window sensor can also use the optional DS18B20 temperature sensor to report the room's temperature - gives you extra functionality and helps optimise your heating control.
- Fibaro 3-in-1 Motion Sensor (Gen5)
Tiny Motion sensor that also monitors temperature - this can also be configured to account for temperature differences if it is positioned near the ceiling.
- Aeon 6-in-1 MultiSensor
Versatile sensor for motion, temperature, light and humidity - control your heating automatically from any of these sensors.
The controller enables you to add and configure devices to your Z-Wave system and run 'schedule scenes'. It also acts as a gateway allowing you to control the system from a smartphone even when you are away from home. In the case of heating, the controller will run the schedules to control when the heating is On/Off and at what temperature, it will also run the hot-water times.
- VERA Plus
Extremely flexible controller for Z-Wave and ZigBee systems.
- VERA Edge
Low cost, very capable Z-Wave controller for heating and complete home automation.
- Fibaro Home Center 2 (HC2)
Flexible Z-Wave controller with an intuitive User Interface (UI), includes dedicated Heating 'panels' for easier schedule and control of your heating system and advanced LUA programming capabilities.
Copyright Vesternet 2016