tekmar 274 Boiler Control User Manual

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Setting the Schedule

Section K

To provide greater energy savings, you can operate the
control on a programmable schedule. The schedule is stored
in memory and is not affected by loss of power to the control.
If a tN4 network is detected the control can become either a
schedule member or schedule master.

Control (CTRL) Schedule (tN4 present)
The schedule only applies to the control. The control follows
its own schedule and the events are not communicated to
tN4 thermostats.

Master Schedule (tN4 present)
If the control is connected to tN4 thermostats, then the
control can operate on a master schedule. You can set up
a maximum of four master schedules on the tN4 Network.
A master schedule is available to all devices on the tN4
network. Master schedules simplify installation since one
master schedule may be used by multiple devices.

To create a master schedule:

Assign the control to be a schedule master by setting
the Heat Schedule item in the Schedule menu to Master
(MST) 1 to 4. After a master schedule is selected, a clock
symbol will appear in the View menu display.

Note: The 274 Setback /Off DIP Switch must be set to

Setback to access the Schedule Menu.

To follow a master schedule:

Assign the control to follow a master schedule by setting
the Heat Schedule in the Schedule menu to Member
(MBR) 1 to 4.

Master

Schedule 1

Member of

Schedule 1

Members of

Schedule 2

Master

Schedule 2

None

Zone

Schedule

274

Zone 1

•

Schedule Types
The schedule type determines when the schedule repeats
itself. This control includes three schedule types:

• 24 Hour: Repeats every 24 hours.

• 5-11: Repeats on a weekly basis. However, it breaks the
week into Saturday and Sunday followed by the weekdays.
This reduces the amount of schedule event settings.

• 7 Day: Repeats on a weekly basis and allows for separate
event times for each day.

Schedule Type

Day

24 Hour

5-11

7 day

Saturday

•

Sunday

•

Monday

•

Tuesday

•

Wednesday

•

Thursday

•

Friday

•

Schedule Mode
The schedule mode can have either 4 or 2 events per day.
An event is a time at which the control changes the target
temperature. The event time can be set to the nearest 10
minutes. If you wish to have the thermostat skip the event,
enter “--:--“ as the time. The “--:--“ time is found between
11:50 PM and 12:00 AM. See the table, Schedule Mode,
for more details regarding types of events.

Schedule Mode Event

24Hr

Sat

Sun

Mon

Tue

Thu

Fri

4 events per day

Wake

6:00 AM

Unoccupied

8:00 AM

Occupied

6:00 PM

Sleep

10:00 PM

2 events per day

Occupied

6:00 AM

Unoccupied

10:00 PM

Boost

Section L

When the control changes from the UnOccupied mode to
the Occupied mode, it enters into a boosting mode. In this
mode, the supply water temperature to the system is raised
above its normal values for a period of time to provide a
faster recovery from the setback temperature of the building.
The maximum length of the boost is selected using the
BOOST setting in the Adjust menu.

Typical settings for the boost function vary between 30
minutes and two hours for buildings that have a fast
responding heating system. For buildings that have a slow
responding heating system, a setting between four hours
and eight hours is typical. After a boost time is selected, the
setback timer must be adjusted to come out of setback some
time in advance of the desired occupied time. This time in
advance is normally the same as the BOOST setting.