Horstmann CentaurPlus C17-ZW Operation instructions

The Horstmann CentaurPlus ZW combined wireless room stat and time control allows
a combi boiler system to have a room thermostat added without the need for any
additional wiring.
Replacing the existing time controller with the CentaurPlus ZW will allow the room
thermostat to be connected wirelessly producing immediate energy savings in houses
where no previous room thermostat has been fitted.
The device is intended to upgrade existing combi boiler systems that do not have
an existing room thermostat. It is not intended for new installations where it will
be necessary to install two heating zones in order to comply with current Building
Regulations.
1
Combined Timeswitch and Room Thermostat
CentaurPlus C17-ZW and HRT4-ZW
User Operating Instructions

The CentaurPlus ZW is a timeswitch which is connected to its own room thermostat - the
HRT4-ZW - using the latest Z-wave wireless technology.
Where it has been used to replace your existing time control it is likely that there was no
room thermostat fitted previously.
The addition of this room thermostat will make considerable energy savings which
independent tests have shown could be as much as 10% off your energy bills.
The thermostat uses the latest micro-processor controlled energy saving software – known
as TPI - which is a very accurate temperature control method compared to older style
mechanical room thermostats. It runs on two AAA batteries which should last more than
2 years and a battery low indicator will appear in the display of the thermostat when
they need changing.
The CentaurPlus ZW timeswitch is mains powered with a reserve battery to retain its
memory during power cuts. It will allow up to 3 On/Off settings per day for each day of
the week and has a 1 hour boost button and an On/Off advance button.
There is also a programme override allowing the permanent selection of OFF/ON/AUTO/
ALL DAY.
2
General system - explanation for householder

The room thermostat will only operate during ‘On’ periods set by the time control which
is always indicated by the red neon indicator light on the front. If there is no light then
the heating is ‘Off’ and the room thermostat is inoperative.
When the timeswitch is ‘On’ (shown by the red
indicator light) the thermostat will be operational
and will provide very accurate control of the room
temperature.
When the thermostat is ‘calling’ for heat the flame
symbol will appear in the thermostat display and if the
timeswitch is ‘On’ the heating will be operative and
will run under the control of the timeswitch and the
temperature set on the room thermostat.
The thermostat is silent in operation – it does not ‘click’ on and off like older style
thermostats. The contacts on the timeswitch will do the actual switching rather than the
thermostat which is linked to it by Z wave wireless signals.
The indicator against the radio mast symbol on the
CentaurPlus ZW shows that the radio link is established.
A flashing indicator means that the wireless connection
has been temporarily lost. This is usually restored by
going to the thermostat and turning the dial up and
down.
If no indicator is present next to the radio mast symbol
then this would suggest that the CentaurPlus ZW
and the HRT4-ZW thermostat have not been paired
correctly on installation. (See pairing instructions in the
Installation Guide).
3
Indicator
light

... an explantion for householders.
Programmers allow you to set ‘On’ and ‘Off’ time periods. Some models switch the central
heating and domestic hot water on and off at the same time; while others allow the
domestic hot water and heating to come on and go off at different times.
Set the ‘On’ and ‘Off’ time periods to suit your own lifestyle. On some programmers you
must also set whether you want the heating and hot water to run continuously, run under
the chosen ‘On’ and ‘Off’ heating periods, or be permanently off.
The time on the programmer must be correct. Some types have to be adjusted in Spring
and Autumn at the changes between Greenwich Mean Time and British Summer Time.
You may be able to temporarily adjust the heating programme, for example, ‘Override’,
‘Advance’ or ‘Boost’. These are explained in the manufacturer’s instructions.
The heating will not work if the room thermostat has switched the heating off. And, if
you have a hot-water cylinder, the water heating will not work if the cylinder thermostat
detects that the hot water has reached the correct temperature.
The above explanation also applies to your timeswitch, which operates as a single
circuit programmer.
What is a programmer?
4

...an explanation for householders
A room thermostat simply switches the heating system on and off as necessary. It works
by sensing the air temperature, switching on the heating when the air temperature falls
below the thermostat setting and switching it off once this set temperature has been
reached.
Turning a room thermostat to a higher setting will not make the room heat up any faster.
How quickly the room heats up depends on the design of the heating system, for example,
the size of boiler and radiators.
Neither does the setting affect how quickly the room cools down. Turning a room
thermostat to a lower setting will result in the room being controlled at a lower
temperature and saves energy.
The heating system will not work if a time switch or programmer has switched it off.
The way to set and use your room thermostat is to find the lowest temperature setting
that you are comfortable with, and then leave it alone to do its job. The best way to do this
is to set the room thermostat to a low temperature – say 18°C – and then turn it up by one
degree each day until you are comfortable with the temperature. You won’t have to adjust
the thermostat further. Any adjustment above this setting will waste energy and cost you
more money.
If your heating system is a boiler with radiators, there will usually be only one room
thermostat to control the whole house. But you can have different temperatures in
individual rooms by installing thermostatic radiator valves (TRVs) on individual radiators.
If you don’t have TRVs, you should choose a temperature that is reasonable for the whole
house. If you do have TRVs, you can choose a slightly higher setting to make sure that
even the coldest room is comfortable, then prevent any overheating in other rooms by
adjusting the TRVs.
Room thermostats need a free flow of air to sense the temperature, so they must not be
covered by curtains or blocked by furniture. Nearby electric fires, televisions, wall or table
lamps may prevent the thermostat from working properly.
What is a room thermostat?
5

6
The CentaurPlus C17-ZW Timeswitch
The simple instructions contained in this user guide are designed to help with the
programming and operation of the unit.
1 SET indicator - RUN is the normal position
2 Time of day
3 Switch period symbol
4 SET button
5 BOOST or adjust (-) button
6 ADVANCE or adjust (+) button
7 ENTER button
8 SELECT or COPY button
9 System ON indicator
10 SETTING positions
11 PROGRAMME settings
12 BOOST symbol
13 ADVANCE symbol
14 AM/PM symbol
15 Day of week indicator
16 PROGRAMME indicator
17 RF signal indicator
1 14
10
17
3
11
12
13
9
4 5 6 7 8
21615

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Manual Overrides
BOOST FUNCTION - 1 HOUR TEMPORARY OVERRIDE
The boost facility will allow the user to boost the system which is currently ‘OFF’ for 1 hour.
To indicate the boost being activated BOOST will be shown on the display for the duration
of the boost period. The system ON indicator will also be illuminated.
ADVANCE FUNCTION – BRINGS FORWARD THE NEXT ON OR OFF OPERATION
The advance facility will allow the user to advance the system to ‘ON’ when currently ‘OFF’
or switch the system ‘OFF’ when currently ‘ON’. To indicate the advance feature being
activated ADVANCE will be shown on the display until the next programme switching time.
The system ON indicator will also be illuminated.
Press BOOST
button:
Your system will
be boosted for
1 hour
Press ADVANCE
button once to
move to the
next ON/OFF
time
At any time
during a BOOST
period press
BOOST again to
return to normal
programming
To cancel the
advance press the
ADVANCE button
again. This will
return the unit
to its normal
programme




AUTO
ALL DAY
24 HRS
OFF
AUTO
ALL DAY
24 HRS
OFF
6:35
6:35
PM
PM
RUN
CLOCK
PROG
RUN
CLOCK
PROG
BOOST
ADVANCE

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Programme Override Facilities
With the CentaurPlus C17-ZW timeswitch operating in the normal running mode it is
possible to alter the functionality of the programme by means of the SELECT button.
The options include:
AUTO - Timeswitch follows all programmed ‘ON’ and ‘OFF’ times.
ALL DAY - Timeswitch operates from 1st ‘ON’ time until 3rd ’OFF’, ignoring all
switching times in between.
24hrs - Timeswitch will be constantly ‘ON’.
OFF - Timeswitch will be constantly ‘OFF’, there is the ability to turn off the
heating during the summer without altering the programme times.
Boost is still available.
All of the settings above will be permanent, i.e. unaffected by programme times, until
alteration by the user.
The diagram below illustrates how to alter the setting, it assumes that the programme is
in the AUTO mode to begin with.
Press SELECT
once.
Programme
goes from
AUTO to
ALL DAY
Timeswitch
will operate
from 1st ON
until 3rd OFF
period
Press SELECT
again.
Programme
goes from
ALL DAY to
24 HRS
Timeswitch
will be
continuously
ON
Press SELECT
again.
Programme
goes from
24 HRS to OFF
Timeswitch
will be
continuously
OFF
Press SELECT
again.
Programme
goes from
OFF to AUTO
Programme
will return
to normal
ON and OFF
times

   
 
AUTO
ALL DAY
24 HRS
OFF
6:35
PM
AUTO
ALL DAY
24 HRS
OFF
6:35
PM
AUTO
ALL DAY
24 HRS
OFF
6:35
PM
AUTO
ALL DAY
24 HRS
OFF
6:35
PM

9
Setting Time of Day and Date
Once the year is set and the
ENTER button is pressed the
process is complete and the
display will return to the run
position
Check that the correct time and DAY are
showing in the display. If the wrong day is
showing in the display that would indicate
that the date has not been set correctly and
the above process should be repeated
Press the
set button
until the set
indicator
is next to
the ‘clock’
position
Use the
+ and –
buttons
to adjust
the hour
and press
ENTER
Use the
+ and –
buttons to
adjust the
minutes
and press
ENTER
Use the
+ and –
buttons
to set
the date
and press
ENTER
Use the
+ and –
buttons
to set the
month
and press
ENTER
Use the
+ and –
buttons
to set
the year
and press
ENTER
    
The CentaurPlus C17-ZW timeswitch has a built in clock and calendar. This will mean that
you will need to enter the date as well as the time on initial set up or if the factory re-set
has been used. Having done this, the clock will automatically adjust for BST/GMT time
changes throughout the year.

Resetting the Timeswitch
Electronic equipment can in some circumstances be affected by electrical interference.
If the timeswitch display becomes frozen or scrambled; or if you wish to revert back to
the default time settings please reset by pressing the SET and SELECT buttons together as
shown below.
After initial installation it is advisable, before programming the CentaurPlus ZW for the first
time, to reset the unit. Resetting can only be achieved with the power ‘ON’ by pressing
the SET and SELECT buttons together. This will return the timeswitch to the factory set
default times.
SET
SELECT
Press the SET and SELECT buttons
together then release the buttons
and the timeswitch will return to
preset factory settings

10
Setting the On and Off Times
To alter these settings please proceed as follows:-
The default time settings shown above are preset at the factory
NB. The factory default settings for the 2nd ON/OFF times are both set at 12:00pm
(midday) which cancels this ‘ON’ period giving 2 ON/OFF periods for the day. If a midday
‘ON’ period is required set the 2nd ON and OFF times accordingly. If not press ENTER twice.
1st ON 1st OFF 2nd ON 2nd OFF 3rd ON 3rd OFF
6.30AM 8.30AM 12.00PM 12.00PM 4.30PM 10.30PM
DEFAULT TIME SETTINGS
Press the
SET button
until SET
indicator
is next
to PROG
position
Repeat this
process for
2nd and 3rd
settings
Use the PLUS and MINUS buttons to
select day required and press COPY.
‘IN’ is displayed to confirm the copy.
Repeat for other days as required
Press ENTER. Use the plus and minus
buttons to select the day required
and press ENTER. Set 1st, 2nd and
3rd times as before. To repeat for
other days go to 2, to copy go to 1
To transfer to independent times
for other days go to 2 or to finish
programming press the SET button
until the SET indicator is in the RUN
position
To finish programming press the SET
button until the SET indicator is in
the RUN position
Use PLUS
and
MINUS
buttons
to adjust
day
Use PLUS
and
MINUS
buttons
to adjust
1st ON
time
Enter the 3rd
OFF time and
the word COPY
is displayed
To set independent
times for other
days go to 2
To follow the copy
route and repeat all
programmed times for
another day go to 1
Use PLUS
and
MINUS
buttons
to adjust
1st OFF
time
Press
ENTER
Press
ENTER
Press
ENTER







 
1
2

11
The aerial symbol complete with radio wave symbols in the display of the
HRT4–ZW thermostat indicates that it is communicating satisfactorily with the
CentaurPlus C17-ZW.
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 switch. If this has no effect please see Z-Wave
pairing instructions.
A radio mast symbol with no radio waves indicates that the HRT4-ZW has not been
signed on to enable it to communicate with the CentaurPlus ZW. 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
details contained in the Installation Instructions.
Further information on how the thermostat operates is contained in the ‘Explanation
for householders’ that precedes this section.
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.
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 Horstmann HRT4-ZW 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.
HRT4-ZW Room Thermostat User Instructions

Battery replacement
The HRT4-ZW runs on 2 x type AAA (Alkaline) non rechargeable batteries and is designed to give
a battery life of approximately two years.
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.
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.
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.
Please dispose of the batteries responsibly.
Low battery symbol
appears first when the
batteries are nearing
the end of their life
Batteries should be
changed immediately
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Horstmann Controls
South Bristol Business Park, Roman Farm Road, Bristol BS4 1UP
E-mail: [email protected].uk
Web site: www.horstmann.co.uk
Leaflet number P84367 Issue 1