19
3
General
venting
Installing vent and air piping
Use only cleaners, primers, and solvents
that are approved for the materials which
are joined together.
NOTICE
PVC/CPVC
All PVC vent pipes must be glued, properly
supported, and the exhaust must be
pitched a minimum of a 1/4 inch per foot
back to the boiler (to allow drainage of
condensate).
NOTICE
⚠
WARNING
The vent connection to the appliance
must be made with the starter CPVC pipe
section provided with the appliance if
PVC/CPVC vent is to be used. The field
provided vent fittings must be cemented
to the CPVC pipe section using an “All
Purpose Cement” suitable for PVC and
CPVC pipe. Use only the vent materials,
primer, and cement specified in Table 3D
to make the vent connections. Failure to
follow this warning could result in fire,
personal injury, or death.
⚠
WARNING
Insulation should not be used on PVC
or CPVC venting materials. The use of
insulation will cause increased vent wall
temperatures, which could result in vent
pipe failure.
This product has been approved for use with the PVC/CPVC
vent materials listed in Table 3D on page 21.
Installation & Operation Manual
Common venting
FTXL boilers may be common vented; however, the following
criteria MUST BE followed:
1. Only FTXL boilers may be connected to the common
vent. DO NOT mix other manufacturer’s appliances or
other Lochinvar models.
2. FTXL boilers connected to the common vent must all be
of the same size.
3. Each FTXL boiler must have a Lochinvar supplied flue
damper installed (see Table 3C).
4. A condensate drain must be installed above the flue
damper.
5. Only vertical direct vent, positive pressure, Category
IV or vertical/chimney vent, negative pressure, Category
II may be used when common venting FTXL boilers.
Sidewall common venting is not allowed.
6. FTXL boilers in a common vent must be connected and
controlled with the integral FTXL SMART SYSTEM
Cascade.
a. The Leader may be controlled through the FTXL
SMART SYSTEM control through BMS (external
0 - 10V signal), ModBus, BACnet, or its own internally
calculated set point.
b. The Cascade (Members) must be controlled by the
FTXL Leader boiler using the Lead/Lag Cascade
option.
For approved common vent sizing, contact the factory.
⚠
WARNING
When FTXL boilers are common vented,
the criteria above MUST BE followed.
Failure to follow all these requirements
will result in severe personal injury, death,
or substantial property damage.
NOTICE
When FTXL boilers are common vented,
hot water generators must be piped
to the primary heating loop and tank
thermostats must not be connected to the
FTXL.
Table 3C
Flue Damper Kits
Flue Damper Kits
Model
Damper Size
Kit Number
1000
6”
100056142
NOTICE
A field supplied inline condensate
collection section MUST BE installed
directly above the backflow preventer.