Installation – tekmar 352 House Control User Manual

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ZONING OPERATION

Single Zone with Indoor Temperature Feedback

The 352 can directly control the space temperature of one heating zone. In order to
measure the indoor temperature and provide indoor temperature feedback, the control
requires either a Room Temperature Unit (RTU) 054 or an Indoor Sensor 076. With an
RTU, the desired indoor temperature is set using the RTU dial; with an Indoor Sensor, the
desired zone temperature is fixed at 70

°F (21°C).

Multiple Zones with no Indoor Temperature Feedback

For systems where no indoor temperature feedback is provided, zone valve end switches
may be used to power up the 352. Since no indoor temperature is available to the control,
the 352 sets the starting point of the heating curve at 70

°F (21°C).

UNOCCUPIED MODE (NIGHT SETBACK)

The 352 can be switched into UnOccupied mode by closing an external switch or a timer
relay wired into the control. When the 352 is in UnOccupied mode and an RTU or Indoor
Sensor is connected, the

UnOcc light turns on and the desired temperature in the zone is

set using the

UnOccupied dial on the control. If no indoor temperature feedback is provided,

the

UnOccupied dial sets the heating curve starting point.

SYSTEM PUMP OPERATION

The

Pump light turns on every time the system pump relay at the back of the control closes. The system pump turns on whenever the

control is not in WWSD.

Pump Exercising

The system pump is exercised to help prevent corrosion from building up and subsequently jamming the equipment. Every three days
the 352 runs the pump for at least 10 seconds.

Installation

Caution

Improper installation and operation of this control could result in damage to the equipment and possibly even personal injury.
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 use as a primary limit control. Other controls that are intended and certified as safety
limits must be placed into the control circuit.

STEP ONE

GETTING READY

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 352 includes:

• One Control 352

• One Outdoor Sensor 070

• One Universal Sensor 071
• Data Brochures D 352, D 070, D 001
• Application Brochures A 352

Other information available:

• Essays

Note Carefully read the details of the Sequence of Operation section in this brochure to ensure that you have chosen the proper control
for your application.

STEP TWO

MOUNTING

Install a 2” x 4” duplex electrical box in accordance with the instructions in the Data Brochure D 001. Determine whether the low voltage
wiring enters the wiring chamber through the back or the bottom of the control. Ensure the depth of the electrical box is enough to house
all the wiring that will be in it.

STEP THREE

ROUGH-IN WIRING

The system pump wiring terminates in the electrical box. All other electrical wiring terminates in the two wiring chambers on the control.
The wiring is roughed-in to the electrical box prior to installation of the control (See Brochure D 001). Standard 18 AWG solid wire is
recommended for all low voltage wiring.

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

• Install the system pump and run the wiring to the electrical box.

• Install the Outdoor Sensor 070 and the Supply Sensor 071 according to the instructions in the Data Brochure D 070 and run the wiring

back to the control mounting location. If indoor temperature feedback is desired, install the RTU 054 or Indoor Sensor 076 according
to the installation instructions provided in the Data Brochure D 054 or D 070 and run the wiring back to the control mounting location.

• Run the wiring from the other system components (boiler, injection valve, etc.) to the control mounting location.

Zone Valve Motor

End Switches

To control

C
R

Indoor Sensor

RTU