Raypak VERSA IC, Инструкция по установке и эксплуатации

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22
A
B
AB
Fig. 21: MODE 3 Hydronic Single - Boiler with Indirect DHW and CWP (MIX TYPE = BOIL)
MODE 3 Single
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 will operate the indirect DHW call with pri-
ority function only. The system will be controlled by the
System Sensor (S3) whenever the indirect call-for-
heat is not active. See
System Sensor Installation
on page 9. The Indirect Sensor (S5) determines the
indirect call/tank set-point. 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 indirect operation via contact closure in lieu of
the tank sensor. The thermostat controller wiring con-
nection is at the the field wiring strip on MVB/XTherm,
or the PIM™ J1 terminal block at terminals 8 and 10.
When using an indirect DHW sensor to control tank
temperature, contact closure is required across the
indirect override connections for proper operation (see
IND Sensor, page 43 for further details). To ensure
proper operation during "limp-along" mode, connect
an aqua-stat across the indirect DHW override termi-
nals, or install a jumper across the Indirect DHW
override terminals and set PIM™ operator dial to be
equal to DHW Target temperature to prevent an over-
temperature condition from occurring. During an
indirect call-for-heat the firing rate is determined by the
Indirect Setpoint (or Max Target) at the Indirect Supply
Sensor (S6). It is important to install this Sensor in a
drywell near the junction between the boiler loop and
Indirect loop for best performance. 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
Maximum distance not to exceed 4 pipe
diameters or 12” whichever is less
CAUTION: Continous pumping through the unit is
not supported and may cause a non-warranty failure.