tekmar 279 Steam Control - Manual (Page 10)

© 2010 D 279 - 05/10 10 of 24
Domestic Hot Water Tankless Coil Section N
The control can replace the mechanical aquastat in the
steam boiler that operates a tankless coil domestic hot
water system with an optional DHW Tankless Coil Sensor.
The sensor is installed into the 1/2” (12 mm) immersion well
that measures the temperature of the tankless coil.
Universal
Sensor
The advantage of using the DHW Tankless Coil feature
is that the control can be programmed to operate the
tankless coil on a night setback schedule. This can lower
fuel usage for domestic hot water heating. The DHW
tankless coil operation of the boiler is separate from the
steam heating operation and is not affected by the heating
system settings.
It is recommended that an anti-scald valve be installed on
the domestic hot water system.
Once the sensor is installed, the DHW Tankless Coil
Sensor /Off switch setting must be set to DHW Tankless
Coil. The DHW Exchange (DHW XCHG) temperature is
visible in the View menu and is a measurement of the DHW
Tankless Coil Sensor. The DHW Tankless Coil temperature
can be set using the DHW XCHG Occupied and the DHW
XCHG Unoccupied settings in the Adjust menu. When the
steam boiler is turned on for DHW tankless coil heating,
the Status field will have a pointer indicating DHW Tankless
Coil Heating.
The DHW Exchange Occupied and Unoccupied target
temperature is maintained with a fixed differential of
10°F (5.5°C). The differential is half above and half
below the target.
Installation
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 279 includes:
One Steam Control 279, One Outdoor Sensor 070, One
Universal Sensor 071, Data Brochures D 279, D 070, D 001,
Application Brochure A 279.
Note: Carefully read the details of the Sequence of
Operation to ensure the proper control was chosen for the
application.
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.
Caution
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