Installation

© 2001 D 364 - 07/01 6 of 36
WARM WEATHER SHUT DOWN (WWSD)
When the outdoor air temperature rises above the WWSD setting, the 364 turns on the WWSD pointer in the display. When the
control is in Warm Weather Shut Down, the Boiler Demand pointer is displayed if there is a demand. However, the control does not
operate the heating system to satisfy this demand. The control does respond to either a DHW demand or a setpoint demand and
operates as described in section C.
BOILER INDOOR (Boil INDR)
The Boil INDR is the room temperature used in the original heat loss calculations for the building. This setting establishes the
beginning of the Characterized Heating Curve for the boiler zones.
BOILER ROOM (Boil ROOM)
The Boil ROOM is the desired room temperature for the boiler zones. It provides a parallel shift of the Characterized Heating Curve.
The room temperature desired by the occupants is often different from the designed indoor temperature (Boil INDR). If the room
temperature is not correct, adjusting the Boil ROOM setting increases or decreases the amount of heat available to the building.
BOILER SYSTEM PUMP (P2) OPERATION
The boiler system pump (Boil Sys Pmp P2) contact (terminals 9 and 10) closes whenever there is a boiler demand and the 364 is
not in WWSD. After the boiler demand is removed, the boiler system pump continues to run for an additional 20 seconds. A boiler
demand can either be an external demand or a boiler zone control as described in section B2.
EXTERNAL BOILER DEMAND
An external boiler demand is generated by applying a voltage between 24 and 240 V (ac)
across the Boil Dem (3) and Com Dem (4) terminals. Once voltage is applied, the Boiler
Demand pointer is displayed in the LCD. If the 364 is not in WWSD, it closes the Prim P1
contact which starts the primary pump and closes the Boil Sys Pmp P2 contact which
starts the boiler system pump. The control turns on the primary pump and boiler system
pump segments in the LCD. If the Boil SENS item is set to SUP, the 364 calculates a
Boil TRG supply temperature. The 364 then fires the boiler, if required, to achieve and /
or maintain the target supply temperature. If the Boil SENS item is set to RET or NONE,
the 364 closes the Boiler contact to enable the boiler control.
BOILER ZONE CONTROL
A tekmar zone control can be used to control the temperature in the boiler zones that are connected to the boiler system pump
(P2). The tekmar zone control is connected to the 364 using the Boil Zo In terminal and Com terminal (25 and 24). The zone control
provides its own internal boiler demand to the 364. In this case, there is no need to provide an external boiler demand as described
earlier. The zone control is also capable of adjusting the Boil TRG temperature, if required, to provide improved building occupant
comfort and system performance.
Section B2: Boiler Demands
Section C: Domestic Hot Water / Setpoint
DHW DEMAND
A DHW demand is generated on the 364 by one of two methods: either an external DHW demand from an aquastat or an internal
demand from a tekmar sensor.
External Demand (Aquastat)
The 364 registers an external demand for DHW when a voltage between 24 and 240
V (ac) is applied across the Setp/DHW and the Com Dem terminals (5 and 4). Either
a DHW aquastat or setpoint control is used as a switch in the DHW demand circuit.
Once the 364 detects a DHW demand, the DHW Demand pointer turns on in the LCD
and the control operates as described on the following page.
Section C1: General
Section C1
General
Section C2
DHW Priority
Section C3
Low
Temperature
Boilers
Section C4
Setpoint
Boil
3
Dem
Com
4
Dem
24 to 240 V (ac)
Com
4
Dem
S
etp/
5
DHW
24 to 240 V (ac)