tekmar 545 Thermostat Installation - Manual (Page 26)

© 2008 D 545 - 07/08 26 of 40
Cycles Per Hour Section D
You can set the number cycles per hour (CPH) for both
the heating and cooling operations. The default setting for
heating cycles per hour is automatic.
Heating CPH:
•
• When the thermostat is connected to a tN4 System
Control, the thermostat uses the CPH setting on the
tN4 System Control for the Heating CPH.
• • To manually set the cycles per hour when the thermostat
is not connected to a tN4 System Control, go to the
Adjust menu and select the Heat CPH item.
• • When the thermostat is connected to a tN4 system with
only thermostats, the SYNC setting synchronizes the
operation of all the thermostats to 5 CPH.
Cooling CPH:
The default setting for cooling cycles per hour is
automatic.
•
• To manually set the cycles per hour, go to the Adjust
menu and select Cool CPH.
Fan CPH:
•
• The fan cycles per hour is tied to the cooling cycles
per hour. When cooling is not used, the fan then uses
1 CPH.
Heating Terminal Units Section E
This thermostat supports Outdoor Reset characterized
heating curves when used in hydronic heating systems. By
setting the correct terminal unit setting, the thermostat can
improve the operation of the heating system. Each stage
of heat has its own terminal unit setting.
Control (CTRL)
Selecting Control as the terminal unit setting on the thermostat
causes the thermostat to adopt the tN4 System Control’s
terminal unit setting.
Hydronic Radiant Floor 1 (HRF1)
Terminal type for a heavy, or high mass, hydronic radiant floor
system. This type of a hydronic radiant floor is embedded in
either a thick concrete or gypsum pour. This heating system
has a large thermal mass and is slow acting.
Hydronic Radiant Floor 2 (HRF2)
Terminal type for a light, or low mass, hydronic radiant
floor system. Most commonly, this type of radiant heating
system is either attached to the bottom of a wood sub floor,
suspended in the joist space, or sandwiched between the
subfloor and the surface. This type of radiant system has
a relatively low thermal mass and responds faster than a
high mass system.
Fancoil (COIL)
A fancoil terminal unit or air handling unit (AHU) consists
of an hydronic heating coil and either a fan or blower. Air
is forced across the coil at a constant velocity by the fan or
blower and is then delivered into the building space.
Temporary Room Set Adjustment (Schedule Only) Section C3
Pressing the up or down button while viewing the Room
or Room Set temperature during scheduled operation
allows for a temporary change in temperature. When the
temporary change is in effect, the words “TMPY HOLD”
are shown on screen. By default, the temporary change lasts for 3 hours. This
duration can be changed by going to the “Temporary Zone
Hold” item in the Scene menu.
The temporary change can be cancelled before it expires
by pressing the Up and Down buttons at the same time.
Wait 10
seconds OR