Velocity Raptor RPTR085, Инструкция по установке и эксплуатации, Страница: 99 / 172

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XII. Operation
(continued)
be configured to provide the functionality of a two zone
zone panel. The system and DHW pump outputs may
be configured as one heating and one domestic or two
heating zones. Circulators are automatically run for
a 20 second exercise period after not being used for
longer than 7 days. Circulator exercise helps prevent
pump rotor seizing.
9. Multiple Boiler Sequencer Peer-To-Peer
Network
The Control includes state-of-the-art modulating
lead-lag sequencer for up to eight (8) boilers capable
of auto rotation, outdoor reset and peer-to-peer
communication. The peer-peer network is truly “plug
and play”. Communication is activated by simply
connecting a RJ45 ethernet cable between boilers.
The Control provides precise boiler coordination
by sequencing boilers based on both header water
temperature and boiler modulation rate. For example,
the lead boiler can be configured to start a lag boiler
after operating at 50% modulation rate for longer
than an adjustable time. The boilers are modulated
in “unison” (parallel) modulation rate to ensure even
heat distribution.
B. Supply Water Temperature Regulation
1. Priority Demand
The Control accepts a call for heat (demand) from
multiple places and responds according to it’s
“Priority”. When more than 1 demand is present the
higher priority demand is used to determine active
boiler settings. For example, when Domestic Hot
Water (DHW) has priority the setpoint, “Diff Above”,
“Diff Below” and pump settings are taken from DHW
selections. Active “Priority” is displayed on the “Boiler
Status” screen.
2. Setpoint Purpose
The Control starts and stops the boiler and modulates
the boiler input from minimum (MBH) to maximum
(MBH) in order to heat water up to the active setpoint.
The setpoint is determined by the priority (Central
Heat or Domestic Hot Water) and as described in the
following paragraphs.
3. Central Heat Setpoint
Upon a Central Heat call for heat the setpoint is
either the user entered Central Heat Setpoint, or is
automatically adjusted by Outdoor Air Reset or, an
Energy Management System (EMS) supplied setpoint.
4. Auxiliary Heat Setpoint
Auxiliary Heat is a second heating demand that may
be used to serve either lower temperature radiation
or warmer heat demands such as fan coils. Upon an
Auxiliary Heat call for heat the setpoint is either the
user entered Auxiliary Heat Setpoint or is automatically
adjusted as Outdoor Air Reset
.
Priority Status Screen
Display
Boiler Responding to:
1st Sequencer
Control
The boiler is connected to the peer-
to-peer network. The boiler accepts
demand from the Sequencer Master.
2nd Domestic Hot
Water
DHW call for heat is on and selected
as the priority demand. DHW is always
higher priority than Central Heat. It also
has higher priority than the Sequencer
Control when DHW priority is “enabled”
and “Boiler Piped” IWH is selected.
3rd Central Heat Central Heat call for heat is on and
there is no DHW demand or DHW
priority time has expired.
4th Auxiliary Heat Auxiliary Heat call for heat is on and
there is no Central Heat or DHW
demand. (NOTE: May be user
selected to be higher priority than
Central Heat.)
5th Frost
Protection
Frost Protection is active and there is
no other call for heat. Frost protection
will be a higher priority than Sequencer
Control if the Sequence Master has no
active call for heat.
6th Warm
Weather
Shutdown
(WWSD)
WWSD is active and the boiler will
not respond to central heat demands.
DHW demand is not blocked by
WWSD.
7th Standby There is no demand detected.
Table 12.1: Order of Priority
5. Outdoor Air Reset
If an outdoor temperature sensor is connected to
the boiler and Outdoor Reset is enabled, the Central
Heat setpoint will automatically adjust downwards as
the outdoor temperature increases. When the water
temperature is properly matched to heating needs there
is minimal chance of room air temperature overshoot.
Excessive heat is not sent to the room heating elements
by “overheated” (supply water temperature maintained
too high a setting) water. Reset control saves energy
by reducing room over heating, reducing boiler
temperature & increasing combustion efficiency and,
reducing standby losses as a boiler and system piping
cool down to ambient following room over heating.
6. Boost Time
When the Central Heat Setpoint is decreased by Outdoor
Air Reset settings the Boost function can be enabled
to increase the setpoint in the event that central heat
demand is not satisfied for longer than the Boost Time
minutes. The Boost feature increases the operating
temperature setpoint by 10°F (5.6°C) every 20 minutes
(field adjustable) the central heat demand is not satisfied.
This process will continue until heat demand is satisfied
(indoor air is at desired temperature), or the central heat
setpoint is reached. Once the heat demand is satisfied,