LAARS Heating Systems
Page 20
4.7 Air Supply and Vent Connections at the Appliance
4.7.2 Direct Venting
The water heater uses 3˝ or 2˝ diameter exhaust and
3˝ or 2˝diameter intake air ducts. To ensure the draw
of air directly from and exhaust of air directly to the
outside of the building, create an airtight seal from the
water heater collar to the vent termination.
(For installations in Canada)
field-supplied plastic
vent piping must comply with CAN/CGA B149.1 (latest
edition) and be certified by the Standard For Type BH
Gas Venting Systems, ULC-S636. Components of
this listed system must not be interchanged with other
vent systems or unlisted pipes or fittings. All plastic
components and specified primers and glues of the
certified vent system must be from a single system
manufacturer and must not be intermixed with another
system manufacturer’s parts.
This water heater has a built-in control to limit the
exhaust temperature.
Tightening — Water Heater Collar (Socket) to
Vent Pipe & Inlet Pipe
Canada has adopted standard ULC S636 which
requires the following additional items.
The following steps for cement application are
highlighted:
Clean and dry your selected PVC, CPVC vent
pipe and Laars Water Heater collar (socket).
- You can select to the size of vent pipe(2˝ & 3˝),
according to the installation conditions.
- Push the pipe into the collar (socket) until it touches
the bottom of the socket fitting.
Water Heater
model
3˝ Combustion Air / Vent Pipe
2˝ Combustion Air / Vent Pipe
Max
Elbow Max
Max
Elbow Max
MSTWW199
100´ (30M)
6
50´ (15M)
4
Table 6. Maximum Vent / Air Pipe Lengths for either 3” or 2 “ Pipes
2” pipe connected, using an adapter
3” pipe
4.7.1 Vent / Air Pipe Lengths
Note : For additional elbows, reduce maximum allowable length
• 5 feet (1.5M) for each additional 3-inch 90-degree elbow
• 2.5 feet (0.75M) for each additional 3-inch 45-degree elbow
• 5 feet (1.5M) for each additional 2-inch 90-degree elbow
• 4 feet (1.2M) for each additional 2-inch 45-degree elbow
• The thickness of the wall vents installed : Min 4˝ ~ Max 20˝
2” to 3”
adapter
is NOT
included.
Summary of Contents for MSTWW
Page 38: ...LAARS Heating Systems Page 36 4 19 Wiring Diagram Figure 3 Wiring Diagram...
Page 39: ...Mascot ST Tankless Water Heater Page 37 4 20 Ladder Diagram Figure 4 Ladder Diagram...
Page 63: ...Mascot ST Tankless Water Heater Page 61 Cover Assembly...
Page 66: ...LAARS Heating Systems Page 64 Notes...
Page 67: ...Mascot ST Tankless Water Heater Page 65 Notes...
