Slant/Fin VHG-100-CH, Installation And Service Manual

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E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
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Boost function
The outdoor reset boost function increases the CH_Setpoint by a prescribed increment (Boost_Temperature_Incr)
if a demand for heat continues beyond the pre-set time limit (Boost_Time_Delay).
Boiler Parameters
(25) Warm Weather Shutdn 72 °F
▲
(26) Boost Temp increment 32 °F
(27) Boost Time Delay 20 min
(28) Night Setback Temp. 40 °F
▼
These are parameters 26 Boost Temp Increment and 27 Boost Time Delay.
They have a default value of 32 °F and 20 min, so the function is switched off and can be activated by the installer
by increasing parameter 26 by a number of degrees. Also, the time can be set when this parameter will be active
in parameter 27 (now set at 20 min).
CH_Setpoint increases again if the demand for heat still is not satisfied in another time increment.
Setpoint adjustment
It is possible to adjust the calculated setpoint with parameter CH_Setpoint_Diff. The calculated setpoint can be
increased or decreased with a maximum of 50 °F (10 °C). The CH setpoint limits (Reset_Curve_Boiler_Minimum
and Reset_Curve_Boiler_Maximum) are respected while adjusting the setpoint.
Apart from the calculated setpoint the functionality is the same as described in paragraph 11.8.1.
Adjustable Outdoor Reset parameters
Parameters display menu # Level Default Value Range
CH_Mode PB1 Installer 1 Mode 0-5
Reset_Curve_Design_Boiler
Sets high boiler CH setpoint when outdoor
temperature is equal to
Reset_Curve_Outdoor_Design.
PB19 Installer 176 ºF (80 ºC) 32…..176 ºF
(0…..80 ºC)
Reset_Curve_Outdoor_Design
Sets the outdoor temp at which the boiler
setpoint must be high as set by
Reset_Curve_Design_Boiler.
PB20 Installer 23 ºF (-5 ºC) -4…..41 ºF
(-20…..5 ºC)
Reset_Curve_Boiler_Mild_Weather
Sets low boiler CH setpoint when outdoor temp.
is equal to
eset_Curve_Outdoor_Mild_Weather.
PB21 Installer 104 ºF (40 ºC) 32…..104 ºF
(0…..40 ºC)
Reset_Curve_Outdoor_Mild_Weather
Sets the outdoor temp at which the boiler
setpoint must be low as set by
Reset_Curve_Mild_Weather.
PB22 Installer 68 ºF (20 ºC) 32…..86 ºF
(0…..30 ºC)
Reset_Curve_Boiler_Minimum
Sets the lower limit for the CH setpoint
(minimum).
PB23 Installer 68 ºF (20 ºC) 68…..194 ºF
(20…..90 ºC)
Reset_Curve_Boiler_Maximum
Sets the upper limit for the CH setpoint
(maximum).
PB24 Installer 185 ºF (85 ºC) 68…..194 ºF
(20…..90 ºC)
Warm_Weather_Shutdown
Set max. outdoor temp. Above this temperature
heat demand is blocked.
PB25 Installer 72 ºF (22 ºC) 32…..95 ºF
(0…..35 ºC)
Boost_Temperature_Incr
CH setpoint increment when heat demand
remains beyond
Boost_Time_Delay.
PB26 Installer 32 ºF (0 ºC) 32…..68 ºF
(0…..20 ºC)
Boost_Time_Delay PB27 Installer 20 min. 1 – 120 min.
CH_Setpoint_Diff
Adjusts the calculated CH setpoint.
PB185 User 0 ºF (0 ºC) -18…..18 ºF
(-10….10 ºC)
Status variables Range
Actual_CH_Setpoint
Calculated CH setpoint, based on outdoor reset curve
68...194 ºF
(20.....90 ºC)
Figure 11.20
Table 11.10
Table 11.11