GSA
Gas-Fired Steam Boilers –
Boiler Manual
10
Part Number 550-110-738/1012
Vent damper
Damper blade
See vent manufacturer’s instructions to install plug (shipped with
damper) in damper hole. Install plug with 3/8” diameter hole in
vent damper hole.
1. Install vent damper as shown in vent damper manufacturer’s
instructions. Vent damper must be installed so that it serves
only one boiler and so damper blade indicator is visible to the
user. See Figure 11.
2. Screws or rivets used to secure the vent damper to the draft
hood must not interfere with rotation of the damper blade.
3. Install damper harness between damper actuator and
knockout in jacket top panel. Use strain relief connectors and
locknuts to secure both ends of damper harness.
Keep wiring harness clear of all hot surfaces. Wire
insulation could be damaged, causing risk of
electrical short-circuit.
4. Read and apply the harness plug warning label (shown above)
so that it is visible after installation
Damper installation
Figure 11
Vent damper assemblies
These systems are used on gas-fired boilers with
vent dampers as shipped from factory. Boiler will not
operate without vent damper installed.
Minimum clearances
Provide a minimum of 6” between the vent damper and any
combustible material. (See “Minimum clearance to combustible
materials,” page 3, for minimum clearance from jacket top to
ceiling to maintain this dimension.).
Do not modify draft hood or vent damper, or make
another connection between draft hood and vent
damper or boiler except as noted below. This will
void CSA certification and will not be covered by
warranty. Any changes will cause severe personal
injury, death or substantial property damage.
2 Prepare boiler
continued
5. Plug damper harness receptacle into damper harness plug.
Bypassing (jumpering) vent damper will cause flue
products such as carbon monoxide to escape into
the house. This will cause severe personal injury or
death.
After
boiler has operated once, if either end of ha
r-
ness is disconnected, the system safety shutdown
will occur. The boiler will not operate until harness
is reconnected.
Effikal or Field Control dampers — Damper hold
open switch must be in Automatic Operation position
for system to operate properly.
Install vent piping
1. Connect from draft hood or vent damper outlet to chimney or
vent with same size vent connector.
2. Where possible, vertical venting to the outside from the draft
hood or vent damper outlet will offer best performance.
3. Where horizontal vent connector is used, slope upward at
least ¼” per lineal foot toward chimney or vent and support
with hangers to prevent sagging.
4. Breeching must not be connected to any portion of a
mechanical draft system that can operate under positive
pressure.
Long horizontal vent connector, excessive number
of elbow or tees, or other obstructions that restrict
the flow of combustion gases should be avoided.
Severe personal injury, death or substantial property
damage could result.