Horstmann C-Stat ZW User Guide

C-Stat 17-ZW

User Instructions

7 Day Wireless Programmable Room

Thermostat and ASR-ZW Receiver

Programmable room thermostats are widely recognised as one
of the best ways in which to control central heating. Horstmann
C-Stat programmable room thermostats have a large display
and intuitive user interface, making them easy to set up and use.
C-Stat uses a sophisticated time proportional integral (TPI)
algorithm for accurate temperature control and energy
efficiency.

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What is a programmable room thermostat?

...an explanation for householders.

A programmable room thermostat is both a programmer and a
room thermostat. A programmer allows you to set 'ON and OFF'
time periods to suit your own lifestyle. A room thermostat works
by sensing the air temperature, switching on the heating when
the air temperature falls below the thermostat setting and
switching it off once the set temperature has been reached.

So, a programmable room thermostat lets you choose what
times you want the heating to be on, and what temperature it
should reach while it is on. It will allow you to select different
temperatures in your home at different times of the day (and
days of the week) to meet your particular needs.

Turning a programmable 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 the boiler and radiators. Neither does the
setting affect how quickly the room cools down. Turning a
programmable room thermostat to a lower setting will result in
the room being controlled at a lower temperature, and saves
energy.

The way to set and use your programmable room thermostat is
to find the lowest temperature settings that you are comfortable
with at the different times you have chosen, and then leave it
alone to do its job. The best way to do this is to set low
temperatures first, say 18ºC and then turn them up by one
degree each day until you are comfortable with the
temperatures. You won't have to adjust the thermostat further.
Any adjustments above these settings will waste energy and
cost you more money.

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If your heating system is a boiler with radiators, there will usually
be only one programmable 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 chose 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.

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.

Programmable 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.

OVERVIEW – EXPLANATION FOR HOUSEHOLDER

Your installer has made an excellent choice and installed one of
the very latest programmable room thermostats manufactured
by Horstmann of Bristol.

Full of the latest technology, the C-Stat has been designed to be
simple to use and adjust whilst still giving accurate energy
saving control over your heating system.

Communication between the thermostat and it's receiver is by Z
Wave wireless RF technology which avoids the need for
additional wiring.

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C-Stat 17-ZW

DISPLAY

Actual Room
Temperature

Antenna
Symbol

Set
Temperature

4

Button

Day of
Week

Time of
Day

Until (Time)

Then (Temp)

+ Button- ButtonBack

Enter
Button

DISPLAY

Actual Room Temperature This is the actual room temperature

Set Temperature This is the temperature that the C-Stat

Until (time) Th is is th e t im e t ha t the ne xt

Then (temp) This is the temperature setting that is

Day of the week It is important that the correct day of the

Time of day This is the current time of day

Setting Buttons Press any button to illuminate the

No Radio Waves Wireless connection not set up

Solid Radio Antenna Z- Wave c omm u ni cat ion p re sen t

ACTIVATING THE BACK-LIT DISPLAY

Press any button to illuminate the display. This will remain illuminated for
10 seconds

GENERAL INFORMATION

During programming please note that the display will return to its normal
operating screen if the last button press exceeds 10 seconds.

measured by the C-Stat

will allow the room to reach. The
temperature range can be set between
5°C and 30°C

When the temperature shown in the
display is achieved the C-Stat will switch
the heating OFF.

If the temperature in the room falls below
the setting the C-Stat will switch the
heating ON.

temperature setting is due to operate

due to operate next

week shows in the display

display.

The message 'To override press -/+ To
see menu press ENTER' will appear

– Flashing Radio Antenna – Temporary
loss of Z-Wave communication

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TEMPORARY OVERRIDE

A temporary temperature change can be made at any time. It is
also possible to extend how long this temperature override is in
operation.

Press ‘-’ or ‘+’ to
adjust temperature

The temperature will revert to its normal programmed setting at
the next timed temperature change

TEMPORARY OVERRIDE WITH TIME EXTENSION
(Maximum of 4 hours)

Press ‘-’ or ‘+’ to
adjust temperature

Press ENTER

The temperature will revert to its normal programmed setting
at the next timed temperature change.

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New temperature
setting will be shown
on the display

New temperature
setting will be
shown on the
display

Press ‘+’ to
adjust the time

Press ENTER

The hours of
the UNTIL time
will flash

PERMANENT OVERRIDE

Press ‘-’ or ‘+’ to
adjust temperature

New temperature
setting will be
shown on the
display

Press ENTER

Press ENTER

Message will
appear briefly
confirming
'Temperature set
until manual
release'

In the 'HOLD' position the temperature can be overridden by
pressing either the '-' or '+' buttons. This will then become the
new 'HOLD' temperature

Press the '+'
repeatedly until
HOLD appears in
the display

The hours of
the UNTIL time
will flash

PERMANENT OVERRIDE – CANCELLATION

Press BACK

Press ENTER

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SETTING UP THE C-STAT

Upon initial installation the C-Stat has the following factory
default settings

Settings – Monday to Friday

Time Target Temperature

Period 1 06:00 am 20 °C

Period 2 08:30 am 18 °C

Period 3 11:30 am 20 °C

Period 4 01:30 pm 18 °C

Period 5 05:00 pm 21 °C

Period 6 10:00 pm 15 °C

Settings – Saturday and Sunday

Time Target Temperature

Period 1 07:00 am 20 °C

Period 2 10:00 am 19 °C

Period 3 11:30 am 21 °C

Period 4 01:30 pm 18 °C

Period 5 05:00 pm 21 °C

Period 6 11:00 pm 15 °C

These can be changed by the installer or the end user at any
time by accessing the MAIN MENU

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