Installation – tekmar 274 Boiler Control User Manual

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2012 274_D

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Installation

Step One — Getting Ready

Caution

Improper installation and operation of this control could
result in damage to the equipment and possibly even
personal injury or death. It is your responsibility to ensure
that this control is safely installed according to all applicable
codes and standards. This electronic control is not intended
for uses as a primary limit control. Other controls that are

intended and certified as safety limits must be placed into
the control circuit. Do not attempt to service the control.
Refer to qualified personnel for servicing. Opening voids
warranty and could result in damage to the equipment and
possibly even personal injury or death.

Check the contents of this package. If any of the contents listed
are missing or damaged, please contact your wholesaler or
tekmar sales representative for assistance.

Type 274 includes:
One Boiler Control 274, One Outdoor Sensor 070, Two
Universal Sensors 082, One 500 Ohm resistor, Data Brochures
D 274, D 070, D 001, Application Brochure A 274.

Note: Carefully read the details of the Sequence of
Operation to ensure the proper control was chosen for
the application.

Remove the control from its base by pressing on the release clip in the wiring chamber and sliding the control away from it.
The base is then mounted in accordance with the instructions in the Data Brochure D 001.

Step Two — Mounting the Base

Step Three — Rough-in Wiring

All electrical wiring terminates in the control base wiring
chamber. The base has standard 7/8” (22 mm) knockouts,
which accept common wiring hardware and conduit fittings.
Before removing the knockouts, check the wiring diagram
and select those sections of the chamber with common
voltages. Do not allow the wiring to cross between sections
as the wires will interfere with safety dividers which should
be installed at a later time.

Power must not be applied to any of the wires during the
rough-in wiring stage.

All wires are to be stripped to a length of 3/8” (9 mm) to
ensure proper connection to the control.
Install the Outdoor Sensor 070 according to the installation
instructions in the Data Brochure D 070 and run the wiring
back to the control.

•

Install the Boiler Supply Sensor 082 according to the
installation instructions in the Data Brochure D 070 and
run the wiring back to the control.
Install the Boiler Return or DHW Sensor 082 according
to the installation instructions in the Data Brochure D 070
and run the wiring back to the control.
Run wires from any security system, alarm panel, or
telephone dialer back to the control.
Run wires from other system components (boilers, pumps,
flow switch, etc.) to the control.
Run wires from the 115 V (ac) power to the control. Use
a clean power source with a 15 A circuit to ensure proper
operation. Multi-strand 16 AWG wire is recommended for
all 115 V (ac) wiring due to its superior flexibility and ease
of installation into the terminals.

•

Step Four — Electrical Connections to the Control

General
The installer should test to confirm that no voltage is present at any of the wires. Push the control into the base and slide
it down until it snaps firmly into place.

Powered Input Connections

Terminals 19 - 25

Power

115 V (ac)

115 V (ac) Power
Connect the 115 V (ac) power supply to the Power L and
Power N terminals (19 and 20). This connection provides
power to the microprocessor and display of the control.