tekmar 546 Thermostat Installation User Manual
Page 29
29 of 44
© 2008
D 546 - 07/08
Room and Floor Sensor
When operating with both room and floor sensors, the
thermostat calculates an on time for the Heat 1 relay to
satisfy the floor sensor’s requirements and on times for
the Heat 1 and Heat 2 relays to satisfy the room sensor’s
requirements. The thermostat operates the Heat 1 relay
for the longer of these two on times.
While the minimum floor temperature is satisfied, the on
times of the Heat 1 and Heat 2 relays are calculated to
satisfy the room temperature requirements.
During heavy loads, the maximum floor temperature setting
limits the on time of the Heat 1 relay. In this situation, the
Heat 2 relay may be on while the Heat 1 relay is off.
Note: During light heating loads, overheating can occur
due to the minimum floor temperature requirements.
Zone Group
Heat 1 Pump = OFF
Zone Manager: Zone Group DIP = On
Operated by
Zone Manager
Operated by
tN4 System Control
Heat 1 Pump = On
Zone Manager: Zone Group DIP = OFF
Zone Group
1st
Stage
2nd
Stage
Mix Water Temperature Bus
Boiler Water Temperature Bus
System Pump Operation
When a tN4 System Control is used, each tN4 bus has a
system pump.
•
• If the tN4 bus’s system pump must turn on when the
Heat 1 relay is on, set the H1 Pump setting in the Adjust
menu to On.
•
• If the tN4 bus’s system pump must turn on when the
Heat 2 relay is on, set the H2 Pump setting in the Adjust
menu to On.
Second Stage Heat Source
The tN4 System Control needs to know whether second
stage heating operates a non-hydronic heating system, a
boiler water temperature zone, or a mixed water temperature
zone.
•
• If using non-hydronic, set to None.
•
• If using boiler temperature water, set to Boil.
•
• If using a mix water temperature, enter the correct Mix
bus number.
Thermal Motor Zone Valves
When using a thermal motor zone valve, system pump
operation must be delayed to allow the thermal motor zone
valve to fully open.
•
• When thermal motor zone valves are used set the Heat
1 Delay setting to On.