Honeywell ST9400A Programmer User guide

The Honeywell ST9400A Programmer is a programmable thermostat that allows you to control the times when your heating and hot water can be switched on. It features a clear display and easy-to-use controls. You can set different programs for heating and hot water, allowing you to save energy and money. You can also use the override buttons to temporarily adjust the settings.

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GUIDE TO THE USE OF THE ST9400A PROGRAMMER:

The purpose of the Programmer is to control the times when the heating and hot water can be switched on.

Normal Use:

Lift the flap to make sure the Slider is in the RUN position.

Also make sure that both hot water and heating are operating in AUTO or

ONCE mode, by pressing the MODE buttons repeatedly until the display shows AUTO or ONCE.

AUTO means on and off twice each day, following the programme.

ONCE means coming on at the first programme time then off at the last programme time.

EXTRA HOUR

OVERRIDE

HOT WATER HEATING

EXTRA HOUR

OVERRIDE

DAY/TIME

HOT WATER

HEATING

RUN

ST9400A

HOT WATER

MODE buttons

HEATING

Slider To turn the hot water and heating OFF:

(1) Keep pressing the hot water MODE button until the display shows that hot water is OFF. If the hot water was on, the light will turn off.

(2) Keep pressing the heating MODE button until the display shows that heating is OFF. If the heating was on, the light will turn off.

To turn the hot water and heating ON:

(1) Keep pressing the hot water MODE button until the display shows

CONT (this is short for continuous). The hot water light will turn on.

The hot water will not turn off in this position.

(2) Keep pressing the heating MODE button until the display shows

CONT (this is short for continuous). The heating light will turn on.

The heating will not turn off in this position.

(1) (2)

Temporary Overrides to the Set Programme:

To turn the hot water ON press the hot water OVERRIDE button – the light will turn ON, unless the hot water is operating in the OFF mode.

To turn the hot water OFF press the hot water OVERRIDE button again

– the light will turn OFF.

This button will only work in the AUTO or ONCE modes. It will NOT work in the OFF or CONT modes.

At the next SET time the Programmer will go back to automatic operation.

(The same applies to the heating OVERRIDE button)

EXTRA HOUR

OVERRIDE

HOT WATER

Hot Water

OVERRIDE button

HEATING

EXTRA HOUR

OVERRIDE

Heating

OVERRIDE button

For a temporary boost of heating or hot water, press the corresponding

EXTRA HOUR button.

Pressing once brings the heating or hot water ON for 1 hour.

Press twice for 2 hours extra, three times for 3 hours extra.

Pressing again will turn the heating OFF.

This button works in the AUTO, ONCE, and OFF modes. It will NOT work in the CONT mode.

If the heating or hot water is already ON, pressing the corresponding

EXTRA HOUR button will add the extra hours to the end of the current

ON period.

EXTRA HOUR

OVERRIDE

HOT WATER

Hot Water

EXTRA HOUR button

HEATING

EXTRA HOUR

OVERRIDE

Heating

EXTRA HOUR button

For guidance on the operation of the other buttons please refer to the complete user instructions supplied with the product.

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Key features

Programmable thermostat
Control heating and hot water
Easy-to-use controls
Clear display
Override buttons
Energy saving

Frequently asked questions

To turn the hot water on, press the hot water MODE button repeatedly until the display shows CONT. The hot water light will turn on and the hot water will not turn off in this position.

AUTO mode means on and off twice each day, following the programme. ONCE means coming on at the first programme time then off at the last programme time.

To turn the hot water ON press the hot water OVERRIDE button - the light will turn ON, unless the hot water is operating in the OFF mode. To turn the hot water OFF press the hot water OVERRIDE button again - the light will turn OFF. This button will only work in the AUTO or ONCE modes. It will NOT work in the OFF or CONT modes.

Pressing once brings the heating or hot water ON for 1 hour. Pressing twice for 2 hours extra, three times for 3 hours extra. Pressing again will turn the heating OFF.