tekmar 162 Setpoint Control Installation User Manual
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© 2007
D 162 - 08/07
the occupied period. During the unoccupied periods,
the exchange supply water temperature is lowered by
the difference between the occupied and unoccupied
setpoints. During the away period, the exchange supply
is lowered by the difference between the occupied and
the away setpoints.
Zone
Group
Pump
tN4 Mix Bus
Setpoint
Control
Mix System
Pump
Boiler
tN4
System
Control
Zone
Manager
Maximum Supply
When the setpoint control is connected to a tN4 system
control and the Heat Source item is set to hydronic (HYDr),
the setpoint control requests an Exchange Supply water
temperature on the tN4 bus. The setpoint control also
includes a Maximum Supply setting. Should the water
temperature on the tN4 bus exceed this water temperature,
then the setpoint control discontinues heating by shutting
off Relay 1.
Relay 1 System Pump
In order to accommodate many different piping and pumping
configurations, the setpoint control is able to choose whether
a “system” pump is required to operate at the same time as
Relay 1. This allows each manifold on a water temperature
to have a “system” pump when using zone valves or when
using zone pumps together with primary secondary piping.
Only the manifold that has zones requiring heat should
have their “system” pump turned on.
When the setpoint control is connected to the tN4 boiler
bus, the “system” pump is the primary pump located on
the tN4 system control.
When the setpoint control is connected to a tN4 mix bus,
the “system” pump is the mix system pump located on the
tN4 system control or on a mixing expansion module.
To turn on the “system” pump together with Relay 1, set
the Relay 1 Pump item in the Adjust menu to On. This is
the factory default.
To turn on Relay 1 without the “system” pump, set the
Relay 1 Pump item in the Adjust menu to Off.
Relay 1 Delay System Pump
In applications where a thermal motor zone valve (telestat)
is operated by Relay 1, a time delay is required to allow
the zone valve to fully open before the “system” pump is
turned on. The time delay is set using the Relay 1 Delay
item in the Adjust menu. When the time delay is set to On
and Relay 1 is turned on, the “system” pump waits for 3
minutes before turning on.
When the setpoint control is connected to the tN4 boiler
bus, the “system” pump is the primary pump located on
the tN4 system control.
When the setpoint control is connected to a tN4 mix bus,
the “system” pump is the mix system pump located on the
tN4 system control or on a mixing expansion module.
Purging
When the setpoint control is used with a tN4 system control,
the setpoint control purges heat from the boiler into the
setpoint zone if it is the last zone to shut off. The length
of the purge is dependent on time, the temperature of the
boiler, and the temperature of the setpoint load.
Priority
When the setpoint control is used with a tN4 system
control, the setpoint control has up to 5 levels of priority
when connected to a tN4 boiler bus and 2 levels of priority
when connected to a tN4 mixing bus. Devices are shut
off in order of their tN4 address, with address ending in
24 having the lowest priority and addresses ending in 01
having the highest priority. See “tN4 Address” for more
information.
Locate the Priority item in the Adjust menu.
When the setpoint control is connected to a tN4 boiler bus,
the priorities are as follows:
STAT = Thermostats have priority over the setpoint control.
The setpoint control no longer heats whenever any
thermostat calls for heat.
OFF = All devices have equal priority.
LO =
The setpoint control has priority over the ther-
mostats. First, all mixing outputs are reduced.
Second, boiler temperature second stage heating
zones are shut off in order of their tN4 address
from 24 to 1. Last, boiler temperature thermostat
zones are shut off in order of their tN4 address
from 24 to 1.
MED = The setpoint control has priority over the thermo-
stats. First, all heating zones are shut off. If there
is sufficient boiler capacity, boiler temperatures
zones are turned on in order of their tN4 address
from 1 to 24. Second, boiler temperature second
stage heating zones are turned on in order of their
tN4 address from 1 to 24. Last, all mixing outputs
are increased up to normal operating levels.
HI =
All thermostat heating zones are shut off whenever
the setpoint control calls for heat.
When the setpoint control is connected to a tN4 mix bus,
the priorities are as follows:
STAT = Thermostats have priority over the setpoint control.
The setpoint control no longer heats whenever
any thermostat calls for heat.
OFF = All devices have equal priority.