Raypak VERSA IC, Инструкция по установке и эксплуатации

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Primary/secondary piping is the only method support-
ed by Raypak to ensure proper boiler and system
functionality while achieving maximum system efficien-
cy.
The system can also be set to operate the indirect
DHW call with or without priority. The boiler firing rate
will be controlled by the System Sensor (S3). The
Indirect DWH Sensor (S5) determines the indirect
call/tank setpoint. The VERSA IC
®
control system also
allows for a thermostat controller (tank-stat) to be
mounted in the indirect tank and provide a call for indi-
rect operation via contact closure in lieu of the tank
sensor. The thermostat wiring connection is at the field
wiring strip on MVB/XTherm, or the PIM™ J1 terminal
block at terminals 8 and 10. When using an indirect
DHW sensor (S5) to control tank temperature, contact
closure is required across the indirect override con-
nections for proper operation (see IND Sensor, page
42 for further details). To ensure proper operation dur-
ing "limp-along" mode, connect an aqua-stat across
the indirect DHW override terminals, or place a jumper
across the indirect DHW override terminals and set the
PIM™ operator dial to be equal to DHW Target tem-
perature.
The VERSA IC
®
will provide Max Delta T (Differential
Temperature) control and will cycle the burner if the
Max Delta T is exceeded between Boiler Outlet Sensor
(S1) and Boiler Inlet Sensor (S2).
In order to enable MIX settings, VERSA
®
DIP #3 must
be set to ON position. Raypak’s Cold Water protection
system utilizes a proportional 3-way valve to bypass
water from the boiler outlet to the inlet during opera-
tion, when the system return water temperature is
below the minimum acceptable level as defined in the
Installation and Operating manual for the product
being installed. (See page 43).
The Boiler Pump (P1) runs during any call for burner
operation and is delayed “off” as user-defined in the
BOILER menu after the burner has shut down. The
System Pump (P2) runs whenever the system is
enabled for heating and the outdoor air temperature is
lower than the WWSD temperature setting (if utilized).
Priority mode toggles the System Pump (P2) off during
an indirect call-for-heat. The Indirect Pump (P3) runs
during an indirect call-for-heat with no “off” delay. The
System Pump is delayed “off” as user-defined in the
SETUP menu.
Mode 2 is used for this configuration. Ensure DIP
switches #1 and 2 on the VERSA
®
Control Board are
in the ON position to make programming changes.
Prior to setting any DIP switches, the heater must be
turned off.
MODE 2 Cascade
The following diagrams will show cascade systems (up
to 4 boilers maximum) with and without CWP in con-
junction with an indirect DHW demand located on the
system loop. The CWP diagrams will show either an
individual 3-way valve at the boiler (MIX Type = BOIL)
or a single 3-way valve providing CWP to all connect-
ed boilers within the cascade (MIX Type = PLNT). The
following piping configurations can be used as fixed
set-point or set up to work in conjunction with an
Outdoor Air Reset Sensor connected to the Master
unit (S4a) to adjust the target water temperature as the
outdoor air temperature changes.
Reverse/return piping is shown and is recommended
to ensure balanced flow through each of the connect-
ed boilers. Primary/secondary piping is the only
method supported by Raypak to ensure proper boiler
and system functionality while achieving maximum
system efficiency.
A
B
AB
Fig. 16: MODE 2 Hydronic Single - Boiler with Indirect
DHW and CWP (MIX TYPE = BOIL )
Maximum distance not to exceed 4 pipe
diameters or 12” whichever is less
NOTE: 0-10VDC firing rate control ignores all
functions except Max Delta T, CWP, Limit and Safety
Switches.
CAUTION: Continous pumping through the unit is
not supported and may cause a non-warranty failure.