tekmar 544 Thermostat Installation User Manual
Page 30

© 2008
D 544 - 07/08
30 of 36
tN4 Address
Section R
When connected to other tN4 devices through a tN4 bus,
the thermostat is automatically assigned a network address.
The tN4 address is useful when trying to correct bus error
open and short circuits.
The address includes the bus water temperature designation
and a device number. The bus water temperature designations
available are Boiler, Mix 1, Mix 2, etc. The device number
can range from 1 to 24. If the thermostat is operating as a
member of a thermostat-only network, the thermostat does
not have an address and the address item in the MISC
menu is not available.
The device number determines the heating priority for each
zone. A thermostat with device number 1 has a higher priority
than device number 24. The tN4 address allows the tN4
system control to shut off low priority zonezs when the heat
source is unable to heat all zones simultaneously. In some
cases, the installer may want to change the thermostat’s
address in order to change the thermostat’s priority relative
to other thermostats.
Note: Keep track of manually set tN4 addresses. When
a tN4 address is manually set, tN4 thermostats using the
Auto Address setting will automatically be assigned new
addresses.
If two thermostats are manually set to the same address, an
error message will appear. The error remains until one of
the addresses is manually changed to a vacant address.
Pump Exercising
Section S
When connected to a tN4 system control, the thermostat
exercises the pump relays for 10 seconds every 3 days.
Exercising helps prevent pump seizure. While the thermostat
is exercising, the display shows “Test”.
Exercising does not occur when:
•
• Mode of Operation is set to Off.
•
• Heat Source is set to Other.
•
• DIP switch 2 is set to None.