Laars Rheos RHCH, Installation And Operation Instructions Manual, Page: 11 / 60

Rheos Boiler and Water Heater
Page 11
above grade directly in line with the exhaust vent
terminal for the horizontally vented gas fueled
heating appliance or equipment. The sign shall
read, in print size no less than one-half (½) inch
in size, “GAS VENT DIRECTLY BELOW.
KEEP CLEAR OF ALL OBSTRUCTIONS”.
4. INSPECTION.
The state or local gas inspector of the side
wall horizontally vented gas fueled equipment
shall not approve the installation unless, upon
inspection, the inspector observes carbon
monoxide detectors and signage installed in
accordance with the provisions of 248 CMR
5.08(2)(a) 1 through 4.
(b) EXEMPTIONS: The following equipment is
exempt from 248 CMR 5.08(2)(a) 1 through 4:
1. The equipment listed in Chapter 10 entitled
“Equipment Not Required To Be Vented” in the
most current edition of NFPA 54 as adopted by
the Board; and
2. Product Approved side wall horizontal vented gas
fueled equipment installed in a room or structure
separate from the dwelling, building or structure
used in whole or in part for residential purposes.
(c) MANUFACTURER REQUIREMENTS
– GAS EQUIPMENT VENTING SYSTEM
PROVIDED. When the manufacturer of
Product Approved side wall horizontally
vented gas equipment provides a venting
system design or venting system components
with the equipment, the instructions provided
by the manufacturer for installation of the
equipment and the venting system shall
include:
1. Detailed instructions for the installation of the
venting system design or the venting system
components; and
2. A complete parts list for the venting system
design or venting system.
(d) MANUFACTURER REQUIREMENTS –
GAS EQUIPMENT VENTING SYSTEMNOT
PROVIDED. When the manufacturer of a
Product Approved side wall horizontally
vented gas fueled equipment does not
provide the parts for venting the fuel gases,
but identifies “special venting systems”, the
following requirements shall be satisfied by
the manufacturer:
1. The identification of each “special venting
system” shall include either the listing of the
website, phone number or manufacturer’s address
where the venting system installation instructions
can be obtained; and
2. The “special venting systems” shall be Product
Approved by the Board, and the instructions
provided with that system shall include a parts
list and detailed installation instructions.
(e) A copy of all installation instructions for the
Product Approved side wall horizontally
vented gas fueled equipment, and all the
venting instructions, parts lists, and/or design
instructions for the venting system shall
remain with the appliance or equipment at the
completion of the installation.
Manufacturers' websites where venting system
installation instructions may be obtained is
located on the Laars website at: http://www.
laars.com.
2.3.2 Side Wall Combustion Air Terminal
The Laars side wall combustion air terminal (see
Table 4) must be used when the heater takes air from a
side wall. Consider the following when installing the
terminal:
1. Do not locate the air inlet terminal near a source
of corrosive chemical fumes (e.g., cleaning fluid,
chlorine compounds, etc.)
2. Locate the terminal so that it will not be subject
to damage by accident or vandalism. It must be at
least 7 feet (2.1m) above a public walkway.
3. Locate the combustion air terminal so that it
cannot be blocked by snow. The National Fuel
Gas Code requires that it be at least 12 inches
(30cm) above grade, but the installer may
determine it should be higher, depending upon
local conditions.
4. If the Rheos is side-wall vented to the same wall,
locate the vent terminal at least 3 feet (0.9m)
horizontally from the combustion air terminal,
and locate the vent terminal at least 1 foot (0.3m)
above the combustion air terminal (see Figure 3).
2.3.3 Vertical Vent Terminal
When the unit is vented through the roof, the
vent must extend at least 3 feet (0.9m) above the point
at which it penetrates the roof. It must extend at least
2 feet (0.6m) higher than any portion of a building
within a horizontal distance of 10 feet (3.0m), and high
enough above the roof line to prevent blockage from
snow. When the combustion air is taken from the roof,
the combustion air must terminate at least 12" (30cm)
below the vent terminal (see Figure 2).