Rheem Raypak MVB 1003A, Installation And Operation Manual

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Combustion
Air Supply
Exhaust
Configuration
Heater Venting
Category
Certified
Materials
Combustion Air
Inlet Material
From Inside Building
(Non-Direct Venting)
Vertical Venting
IV
Category IV
Stainless Steel
UL Listed
Horizontal
Through-the-Wall Venting
From Outside Building
(Direct Venting)
Vertical
Venting
Galvanized Steel
PVC
ABS
CPVC
Horizontal
Through-the-Wall Venting
Table I. Venting Category Requirements
Alarm Connection
An alarm annunciator or light may be connected to the
alarm contacts on the boiler PIM. The Alarm Contacts
are 3A rated dry contacts on a normally-open relay that
close during fault or lockout conditions, and the maximum
voltage across the contacts is 30 VAC or 30 VDC. See
Figure 22 .
In a cascade system, the alarm output of the master
boiler will be active if either the master boiler or follower(s)
have a lockout condition (This feature can be enabled or
disabled, refer to VERSA IC
®
manual 241493 for further
details on "Cascaded Alarm".). The alarm output of the
follower boilers will only energize if a lockout condition
occurs on that specific boiler.
Venting - General
A CAUTION: Proper installation of flue venting is
critical for the safe and efficient operation of the heater.
Appliance Categories
Heaters are divided into four categories based on the
pressure produced in the exhaust and the likelihood of
condensate production in the vent.
Category I – A heater which operates with a non-positive
vent static pressure and with a vent gas temperature that
avoids excessive condensate production in the vent.
Category II – A heater which operates with a non-positive
vent static pressure and with a vent gas temperature that
may cause excessive condensate production in the vent.
Category III – A heater which operates with a positive
vent pressure and with a vent gas temperature that avoids
excessive condensate production in the vent.
Category IV – A heater which operates with a positive
vent pressure and with a vent gas temperature that may
cause excessive condensate production in the vent.
See
Table I for appliance category requirements.
Use only the special gas vent pipes listed for use with
Category IV gas burning heaters, such as the AL29-4C
stainless steel vents offered by Heat Fab Inc. (800-772-
0739), Protech System, Inc. (800-766-3473), Z-Flex (800-
654-5600) or American Metal Products (800-423-4270).
Pipe joints must be positively sealed. Follow the vent
manufacturer’s installation instructions carefully.
NOTE: For additional information on appliance
categorization, see appropriate ANSI Z21 Standard
and the NFGC (U.S.), or B149 (Canada), or applicable
provisions of local building codes.
A CAUTION: Condensate drains for the vent piping
are required for installations of the MVB. Follow vent
manufacturer instructions for installation and location of
condensate drains in the vent. Condensate drain must
be primed with water to prevent gas flue leak and must
be routed to an appropriate container for neutralization
before disposal, as required by local codes.
A WARNING: Contact the manufacturer of the vent
material if there is any question about the appliance
categorization and suitability of a vent material for
application on a Category IV vent system. Using improper
venting materials can result in personal injury, death or
property damage.
A CAUTION: Vent piping is hot. Raypak recommends
the use of double wall or insulated wall pipe to prevent
personal injury.
NOTE: Ensure that clearances are maintained per
Tables C and D.
Extractors, draft inducers, and motorized
flue dampers
When extractors or inducers are used in the venting system,
they must be interlocked with each connected appliance, to
ensure proper operation. If Individual motorized dampers
are used, they must be interlocked to their respective
appliance. See the "Field Wiring Connection" on page
22 of this manual for proper wiring instructions, using
Fan/Damper dry contacts and external interlock.