STEP BY STEP: LET’S TAKE CONTROL
Vokèra takes us through the latest OpenTherm and Weather Compensation controls for its Unica i gas boiler and explain the
techniques for a hassle-free installation.
Vokèra RF 7-day OpenTherm programmable
room thermostat
Step One: Receiver installation
Launched in conjunction with Vokera’s new Unica i boiler range,
the RF 7-day OpenTherm Programmable Room Thermostat
provides the user with complete domestic heating and hot water
control at the touch of a button. It comprises a battery operated
transmitter and a wired receiver. The transmitter can be located
within any heated area of the dwelling, up to 25-metres from the
receiver.
Decide on an appropriate place to mount the receiver and either
fixto the wall or to the side of the boiler using the magnetic strips
provided. The receiver comes pre-wired with a Tyco connection
and is designed to be mounted close to the boiler.
Step Two: Connecting the receiver to the boiler
OpenTherm explained
Remove the boiler casing and lower the control panel to reveal the
male Tyco connection that is already pre-wired in the new Vokera
Unica i boiler. The installer then simply needs to connect the
receiver. There is no simpler control to fit to a boiler, plus there is
no need for an electrician!
How does OpenTherm help customers save up to £67 a year
on their gas bills?
This control samples the room temperature in the normal way.
When a room requires heat to bring it up to the desired
temperature the boiler will operate at a high flow temperature
to achieve the target temperature as quickly as possible.
As the room approaches the target temperature, the Vokèra
OpenTherm control communicates to the boiler through the
wireless receiver to reduce the flow temperature to the heating
system, thereby avoiding an overshoot or overheating the
room.
When the room is at its target temperature, the OpenTherm
control transfers information to the boiler, to operate it at a
temperature, low enough to combat heat loss, but no higher.
This is important because the lower the heating flow
temperature of the condensing boiler, the more efficient it will
be since it will be able to operate more frequently in
condensing mode.
Understanding the user interface
Weather Compensation on the new Unica i
Vokèra’s OpenTherm control displays adjustable:
Date and time; and
Current temperature.
Like many of our Vokèra models, the new Vokera Unica i
comes complete with weather compensation technology built
in. This means that by simply purchasing an external sensor,
the homeowner can benefit from even further energy savings.
It displays useful information for both the installer and user:
Service reminders;
Error codes; and
Fault history
for straight forward diagnostics and repair.
Weather compensation technology ‘fine tunes’ the heating
system to the outside temperature condition, where the flow
temperature increases or decreases in response to external
weather conditions.
What’s more - with a list price of just £95 – this level of control
doesn’t have to be costly.
Working with the OpenTherm control, the weather
compensation technology takes the external temperature into
consideration and tells the boiler to compensate accordingly.
For example, if it is a warm day, the boiler will not need to work
as hard to achieve the room set point and therefore energy
usage and costs can be significantly reduced.
Step One:
Step Two:
Start by installing the weather compensation control to an external
North/North West facing wall and connect a 0.5mm flex.
Usingthe 0.5mm flex you have connected to the weather compensation
sensor connect to the boiler PCB.
Boiler flow temperature
High temperature (radiator)
system curves
Step 3
Selecting the heating curve
When the weather compensation sensor is connected, a ‘heating curve’ must be chosen, which can be done via the OpenTherm
control.
The heating curve is a setting that gives the controller information it needs about the heating system, geographic location and
insulation level in the house so it can set the boiler flow temperature accurately (for example, if the house requires a flow to the
radiators of 70°C to provide an internal temperature of 20°C when the outside temperature is - 4°C, a suitable curve must be chosen
from the graph).
Traditionally, radiators have been sized to deliver the required internal temperature of 20°C with an external temperature of -3°C and
a flow temperature of 75 to 80°C. That design of system will require a curve setting of around 2.5mm and is a good starting point.
We offer more guidance on the correct curve selection on our website.
The installation of these two energy saving controls is extremely straight-forward and provides the end user with enhanced comfort
and energy savings.
View the step by step installation video online at: http://www.youtube.com/watch?v=SdXfHG2gx4g.