Secure SRT321 Operating instructions

SRT321
User and Installation Instructions
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Electronic Room Thermostat &
Temperature Sensor (Tx) - Z-Wave

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The SRT321 is a wireless electronic battery powered
room thermostat that uses interoperable two-way RF
mesh networking technology to provide optimum
comfort with close control of the energy used to heat the
home without the need for additional wiring or unsightly
cable runs.
The SRT321 will only operate when 2 x AAA batteries
have been fitted.
This document provides information specific to the Z-
wave technology implemented on SRT321, to ensure
correct interoperability between third party devices.
The SRT321 has been developed to control central
heating systems where the demand temperature can
be set locally or remotely to a third party device. The
SRT321 also has the capability to act as a temperature
sensor.
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The Secure SRT321 thermostat uses the latest control
technology to provide extremely accurate temperature
control which will help to keep your energy usage as
low as possible without affecting your comfort levels. In
fact comfort levels may well be improved as the control
accuracy should ensure that the room does not
‘overheat’ before switching off.
The display will show the
required temperature
setting and can be
adjusted in increments of
1°C.
To adjust the required
temperature setting turn
the dial anti clockwise to
decrease it and clockwise
to increase it.
USER INSTRUCTIONS
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When the thermostat is in the ‘call for heat’
condition a flame symbol will appear in the
display.
Pressing the temperature setting dial will allow
the user to check the current actual measured
room temperature which will be displayed for
approx 7 seconds before returning to the set
temperature.
The aerial symbol complete with radio wave
symbols in the display of the SRT321
thermostat indicates that it is communicating
satisfactorily with the rest of the system.
A flashing radio wave indicates a loss of
communication. This may be temporary and can often
be restored by turning the thermostat dial and
increasing or decreasing the temperature to make the
thermostat send a temperature update to a controller. If
this has no effect please see Z-Wave pairing
instructions on page 6. 5

A radio mast symbol with no radio waves
indicates that the SRT321 has not been
signed on to enable it to communicate with
the Z-Wave system. In this case you may
wish to contact the Installer as the indication
is that the product has not been commissioned when
the installation took place. Alternatively see the Z-Wave
pairing instructions on page 12.
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Battery Replacement
The SRT321 runs on 2 x type AAA (Alkaline) non
rechargeable batteries and is designed to give a battery
life of approximately two years – under normal usage
conditions.
Battery should
be changed
immediately
Low battery symbol
appears first when
the batteries are
nearing the end of
their life.
When the batteries are
nearing the end of their life
a low battery symbol will
appear in the display and
the batteries should be
changed within a few days.
If the batteries are not changed at this point eventually a
‘LO’ battery message flashes intermittently in the
display and if this happens the batteries should be
changed immediately.
To change the batteries it is necessary to remove the
thermostat from the wall. To do this first undo the two
captive screws at the base of the thermostat and swing
the thermostat up and away from the wall plate.

Please dispose of old batteries
responsibly
Remove the old batteries and replace
them with two new AAA size alkaline
batteries ensuring that they are fitted
correctly as indicated by the terminal
markings in the battery compartments.
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Once the batteries are fitted, re-fit the thermostat to the
wall plate by engaging with the lugs at the top of the wall
plate and push the thermostat into position. Locate it
over the captive screws at the base of the wall plate and
tighten so that the thermostat is locked into position.
Check the temperature setting is correct and adjust if
necessary.

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Fitting the SRT321 Room Thermostat
Avoid installing the thermostat against or behind any
large metal surfaces which could interfere with the radio
signals. The SRT321 should be mounted on an internal
wall approximately 1.5 metres from floor level using the
wall plate provided and should be in a position away
from draughts, direct heat and sunlight. Ensure that
there will be enough space to allow easy access to the
two retaining screws located at the base of the wall
plate.

Offer the plate to the wall in the position where the
SRT321 is to be mounted and mark the fixing positions
through the slots in the wall plate. Drill and plug the wall,
then secure the plate into position. The slots in the wall
plate will compensate for any misalignment of the
fixings.
Complete the installation by swinging the room
thermostat into position by engaging with the lugs at the
top of the wall plate before pushing it carefully into its
plug-in terminal block.
Tighten the 2 captive screws on the
underside of the unit.
Now ensure that the system is
responding to the ON/OFF commands
from the Room Thermostat and explain its operation to
the householder before handing over these User
Instructions.
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