Raypak 88AR-398A, Installation & Operating Instructions Manual

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Venting
General
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-pos-
itive vent static pressure and with a vent gas
temperature that avoids excessive condensate pro-
duction in the vent.
Category II – A heater which operates with a non-pos-
itive 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 M for appliance category requirements.
Use only PVC or CPVC vent material (in Canada,
ULC-S636 approved plastic material must be used) or
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 Product (800-423-4270).
Pipe joints must be positively sealed. Follow the vent
manufacturer’s installation instructions carefully.
DuraVent
®
polypropylene vent material is also
approved to be used on XPak FT products.
Vent installation shall be in accordance with Part 7,
Venting of Equipment, of the NFGC, ANSI
Z223.1/NFPA 54, Section 7, Venting Systems and Air
Supply for Appliances, of the B149 Code, or applicable
provisions of the local building codes.
NOTE: For additional information on appliance
categorization, see the ANSI Z21.13 Standard and
the NFGC (U.S.), or B149 (Canada), or applicable
provisions of local building codes.
CAUTION: Proper installation of flue venting is
critical for the safe and efficient operation of the
boiler.
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.
Alarm Connection
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 con-
tacts is 30 VAC or 30 VDC. Connections are made at
the supplied alarm contacts (spade terminals).
In a cascade system, the alarm output of the master
boiler will be active if either the master boiler or fol-
lower(s) have a lockout condition. The alarm output of
the follower boilers will only energize if a lockout con-
dition occurs on that specific boiler.
WARNING: Do not use foam core or cellular core
PVC/CPVC pipe for venting.
WARNING: DO NOT insulate PVC or CPVC vent
pipe.
CAUTION: When using stainless steel vent in a cli-
mate where freezing may occur, a double wall vent
pipe must be used.
Support of Vent Stack
The weight of the vent stack or chimney must not rest
on the heater vent connection. Support must be pro-
vided in compliance with applicable codes. The vent
should also be installed to maintain proper clearances
from combustible materials. Use insulated vent pipe
spacers where the vent passes through combustible
roofs and walls.
CAUTION: The inlet water temperature to the XPak
FT must not exceed 170ºF at any firing rate to use
the PVC venting option. The venting system must
conform to local codes and/or the current National
Fuel Gas Code ANSI Z223.1/NFPA 54. The system
setpoint must not exceed 180°F.