tekmar 263 Boiler Control User Manual

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UnOccupied Switch

If an external timer (tekmar Timer 032) or switch is used, connect the two wires from the
external switch to the Com and UnO Sw terminals (17 and 18). When these two terminals
are shorted together, the control registers an unoccupied (UNOCC) signal.

STEP FIVE

——————

TESTING THE WIRING

General

Each terminal block must be unplugged from its header on the control before power is applied for testing. To remove the terminal
block, pull straight down from the control.

The following tests are to be performed using standard testing practices and procedures and should only be carried out by
properly trained and experienced persons.

A good quality electrical test meter, capable of reading from at least 0 to 300 V (ac) and at least 0 to 2,000,000 Ω, is essential to
properly test the wiring and sensors.

Test The Sensors

In order to test the sensors, the actual temperature at each sensor
location must be measured. A good quality digital thermometer with
a surface temperature probe is recommended for ease of use and
accuracy. Where a digital thermometer is not available, a spare sensor
can be strapped alongside the one to be tested and the readings
compared. Test the sensors according to the instructions in the Data
Brochure D 070.

Test The Power Supply

Make sure exposed wires and bare terminals are not in contact with
other wires or grounded surfaces. Turn on the power and measure
the voltage between the Power L and Power N terminals (7 and 8)
using an AC voltmeter, the reading should be between 103.5 and
126.5 V (ac).

Test the Powered Inputs

Boiler Demand

If a boiler demand is used, measure the voltage between the
Boil Demand

terminals (1 and 2). When the boiler demand device

calls for heat, between 20 and 260 V (ac) should be measured at the
terminals. When the boiler demand device is off, less than 5 V (ac)
should be measured.

DHW Demand

If a DHW demand is used, measure the voltage between the
DHW Dem

and the Com Dem terminals (3 and 4). When the DHW

demand device calls for heat, between 20 and 260 V (ac) should be
measured at the terminals. When the DHW demand device is off,
less than 5 V (ac) should be measured.

Com

UnO

Timer Switch

Boil

Com

Power

103.5 to 126.5 V (ac)

20 to 260 V (ac)

Boiler

Demand

20 to 260 V (ac)

DHW

Dem

Com

Dem