Service manual

7
A qualified professional using a proven vent-
sizing program with input of accurate operating
parameters must properly calculate sizing of the
venting system. In applications where flue gas
temperatures are lower than can support a
Category II with conventional negative draft, it
will be determined at the venting design stage
that a positive pressure will be developed in the
vent. It will then be necessary to either provide
separate vents as for Category IV, or to provide
an extractor at the chimney outlet in order to
maintain a negative draft in the chimney and
allow common venting.
The chimney must be protected from down
drafts, rain and debris by using a listed chimney
cap. Approval of the installation will be at the
discretion of authorities having jurisdiction.
Sidewall and Vertical Venting
The maximum vent length is 60 equivalent feet.
Vent pipe may be run through a vertical or
horizontal chase provided that minimum
clearances to combustible materials are
maintained. The vent should terminate a
minimum 12 inches above grade plus normally
expected snow accumulation, or 7 feet above
grade if located adjacent to public walkways. Do
not install over public walkway where local
experience indicates condensation or vapour
from the appliance creates a nuisance or
hazard.
Minimum 3 feet above any forced air inlet
located within 10 feet of vent termination.
Minimum 4 feet below, 4 feet horizontally or
above any door window or gravity air inlet.
Minimum 4 feet horizontally from electric meters,
gas meters, regulators and relief valves. Use
appropriately designed thimbles when passing
through combustible walls or roofs. Install fire
stops where vent passes through floors, ceilings
or framed walls. The fire stop must close the
opening between the vent pipe and the
structure. Locate vent terminal above
combustion air intake terminal (if used) and no
closer than 2 feet vertically or horizontally.
Vertical venting requires flashing and a storm
collar to prevent moisture from entering the
structure. Vertical vent termination must be at
least 2 feet plus the expected snow
accumulation above the roof penetration height.
7 WATER PIPING
Check all applicable local heating, plumbing and
building safety codes before proceeding.
With the boiler off, open makeup water valve
and allow system to fill slowly. Adjust the
pressure regulator to provide at least 15 PSIG in
the system when cold.
The circulating pump must be installed at the
appliance inlet. Always pump toward the heat
exchanger. Minimum operating system pressure
must not drop below 30 PSIG when hot.
With all vents open, run system circulating pump
for a minimum of 30 minutes with the boiler off.
Open all strainers in the circulating system and
check for debris.
Check liquid level in expansion tank. With
system full of water at 15 PSIG, the level of
water in the expansion tank should not exceed
¼ of the volume with the balance filled with air.
Start up boiler following instructions provided.
Operate entire system including pumps and
radiation for at least 1 hour.
Improper piping of this appliance will void the
manufacturer’s warranty. Improper piping
arrangement may cause heat exchanger tube
failure resulting in flooding and extensive
property damage. Excessive water hardness
causing scaling in the copper heat exchanger
tubes is not covered under the manufacturer’s
warranty. Excessive pitting and erosion of the
internal surface of the copper heat exchanger
tubes due to high water velocity or chemicals is
not covered under the manufacturer’s warranty.
Improper operation of this appliance by
permitting return water temperature below 130
o
F
(55
o
C) will result in flue gas condensation
leading to corrosion deposits on the heat
exchanger tubes and will void the warranty.
To eliminate trapped air, install venting devices
at high points in the system as well as in the
piping on the suction of the pump and in the
piping on the discharge of the appliance.
Suitable pipe hangers or floor stands must
support the weight of all water and gas piping.