tekmar 265 Boiler Control - Manual (Page 4)

© 2010 D 265 - 07/10 4 of 36
Section A
General
Operation
Page 4 - 6
Section B
Boiler
Operation
Page 6 - 10
Section C
Outdoor
Reset
Page 10 - 12
Sequence of Operation
Section A: General Operation
The following defined terms and symbols are used throughout this manual to bring attention to the presence of hazards of various risk
levels, or to important information concerning the life of the product.
- Warning Symbol: Indicates presence of hazards which can cause severe personal injury, death or
substantial property damage if ignored.
- Double insulated
- Local level, appliances
INSTALLATION
CATEGORY II
Definitions
Section D
DHW
Operation
Page 13 - 15
Section E
Setpoint
Operation
Page 16
Section F
External
Input Operation
Page 17 - 18
Section G
Pump
Operation
Page 18 - 19
POWERING UP THE CONTROL
When the control is powered up, all segments in the LCD are turned on for 2 seconds. Next, the control displays the control type
number in the LCD for 2 seconds. Next, the software version is displayed for 2 seconds. Finally, the control enters into the normal
operating mode.
BOILER TARGET TEMPERATURE
The control operates up to three modulating boilers to control the supply water temperature to a hydronic space heating system
or setpoint. When using the control to provide Domestic Hot Water (DHW) requirements, only two modulating boilers can be
operated. The supply water temperature is based on boiler reset, an external 0 – 10 V (dc) signal, DHW requirements, or a
setpoint temperature.
Boiler Reset (Stand Alone)
When a boiler demand signal from the heating system is present,
the control operates the boiler(s) to maintain the supply temperature
based on the outdoor air temperature and the Characterized Heating
Curve settings. Refer to section C.
DHW
When a DHW demand is present, the control operates the boiler(s)
to maintain the supply water temperature at least as hot as the DHW
exchange setting. Refer to section D.
Setpoint
When a setpoint demand signal is present, the control operates the boiler(s) to maintain the supply water temperature at least as
hot as the Setpoint setting. Refer to section E.
External Input 0 – 10 V (Dc) or 2 – 10 V (Dc)
When an external input signal is present, the control converts the signal to a target supply temperature. The control operates the
boiler(s) to maintain the required supply water temperature. Refer to section F.
Decreasing Outdoor Temperature
Incr
easing W
a
ter T
e
mper
atur
e Terminal Unit Terminal Unit
Indoor Design Indoor Design Outdoor Design Outdoor Design
Design Supply Design Supply