NTI Triton VS80 Assembly, Installation And Operation Instructions page 19

VS80-130
Inferring Heat Load ("Automatic Means" of Adjusting Boiler Temperature)
The HydroStat control incorporates two (2) options for Inferring Heat Load:
1) Thermal Targeting Method – default method
2) Outdoor Reset Method – method used when outdoor sensor is connected to OR and C
1) Thermal Targeting Method:
 Default method for satisfying central heat demands.
 For the duration of a central heat demand, the target temperature is boosted by 10ºF every Boost Interval.
 For each new central heat demand, the control reduces the target temperature established in the previous cycle
by 5ºF.
 For every 30 minutes of no central heat demand, the control will reduce the target temperature by 5ºF.
 The Subtractive Differential establishes how much the boiler temperature must drop below the target
temperature, before the burner will fire for a central heat demand.
 The Economy Feature setting determines the Boost Interval and Subtractive Differential values; see Table 7-4.
 Thermal Targeting is overridden when Economy Feature is set to OFF, i.e. central heat demands operate to the
HI TEMP setting.
 A central heat demand is activated by a T-T demand or ZC-ZR demand when the Zone / Indirect switch is set to
"Z".
 With an Outdoor Sensor connected to WWSD and C, the control will perform Warm Weather Shutdown and
Thermal Targeting.
 With an Outdoor Sensor connected to OR and C, the control will override Thermal Targeting and instead
function as an Outdoor Reset control with Warm Weather Shutdown – see 2) Outdoor Reset Method below.
Table 7-4 Economy Feature Setting (for Thermal Targeting)
Subtractive
1
Setting
Differential
Interval
o
OFF 10 F
o
LO
20 F
o
1
20 F
o
2
20 F
o
3
20 F
o
4
20 F
o
5
20 F
o
HI 20 F
Notes:
1 - Do not include Indirect Water Heaters in the number of heating zones.
Installation Checklist - Installation & Operation Instructions
Boost
Recommended Settings and Applications
2
Disables Thermal Targeting. Applications where a boiler must fire to the High
N/A
Limit (HI TEMP setting)
Lowest level of fuel savings. Use only if other settings can't meet the demand load.
10 min
15 min 1 zone heating system.
20 min 2 zone heating system.
25 min 3 zone heating system.
30 min 4 zone heating system.
35 min 5 zone heating system.
40 min Maximum efficiency. Highest level of fuel savings.
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Triton
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