Unit Location; Combustible Material And Service Clearances; Unit Mounting Methods - Modine Manufacturing DBS Installation And Service Manual

UNIT LOCATION / UNIT MOUNTING METHODS

UNIT LOCATION

DANGER
Appliances must not be installed where they may be exposed
to a potentially explosive or flammable atmosphere.
IMPORTANT
To prevent premature heat exchanger failure, do not locate
ANY gas-fired appliances in areas where corrosive vapors (i.e.
chlorinated, halogenated or acid) are present in the atmosphere.
Location Recommendations
1. When locating the furnace, consider general space and
heating requirements, availability of gas and electrical
supply, and proximity to vent locations.
2. Unit must be installed on the positive pressure side of the
circulating blower.
3. Be sure the structural support at the unit location site is
adequate to support the weight of the unit. For proper
operation the unit must be installed in a level horizontal
position.
4. Do not install units in locations where the flue products
can be drawn into the adjacent building openings such
as windows, fresh air intakes, etc.
5. Be sure that the minimum clearances to combustible
materials and recommended service clearances are
maintained. Units are designed for installation on non-
combustible surfaces with the minimum clearances shown
in Figure 4.1 and Table 4.2.
6. Units installed downstream of refrigeration systems, or
exposed to inlet air temperatures of 40°F or less, may
experience condensation, therefore, provisions should
be made for disposal of condensate. Means have been
provided in the bottom pan of the unit to accommodate a
condensate drain line connection flange.
7. When locating units, it is important to consider that the
combustion air and exhaust vent piping must be connected
to the outside atmosphere. The maximum equivalent
lengths are listed in Table 7.1 on page 7.
8. In garages or other sections of aircraft hangars such as
offices and shops which communicate with areas used
for servicing or storage, keep the bottom of the unit at
least 7" above the floor. In public garages, the unit must
be installed in accordance with the Standard for Parking
Structures NFPA #88A and the Standard for Repair
Garages NFPA#88B. In Canada, installation of unit
heaters in airplane hangars must be in accordance with
the requirements of the enforcing authority, and in public
garages in accordance with the current CAN/CGA-B149
codes.
9. Do not install units in locations where gas ignition system is
exposed to water spray, rain, or dripping water.
10. All mechanical equipment generates some sound
and vibration that may require attenuation. Libraries,
private offices and hospital facilities will require more
attenuation, and in such cases, an acoustical consultant
may be retained to assist in the application. Locating
the equipment away from the critical area is desirable
within ducting limitations. Generally, a unit should be
located within 15 feet of a primary support beam. Smaller
deflections mean lesser vibration and noise transmission.
4
Figure 4.1 - Combustible Material Clearances
Model Size Access Side (A)
75 thru 175 1"
200 thru 960 2"
NON-ACCESS
SIDE = 0"
j A 3'' minimum clearance to combustible material is required from the vent collar.
Table 4.2 - Recommended Service Clearances
Model Size Access Side
75 18"
100/125 20"
150/175 25"
200/225 27"
250/300 30"
350/400 41"
500/600 30"
700/800 41"
840/960 41"

UNIT MOUNTING METHODS

Determine the method of mounting that will be used. Be sure
the method of unit support (suspension or floor mounting) is
adequate to support the weight of the unit (see Weights for base
unit and factory installed option weights). For proper operation,
the unit must be installed in a level horizontal position.
Combustible material and service clearances as specified in
Figure 4.1 and Table 4.2 must be strictly maintained. To assure
that flames are directed into the center
of the heat exchanger tubes, the unit must be level in a
horizontal position.
Unit Suspension
Four 3/4" diameter suspension hanging locations are provided
in the base rail assembly of the unit. Refer to Figure 46.1 for
Suspension Hanging Locations and Figure 5.1 demonstrates
how the unit should be suspended and fastened to the unit base
rail. If required, vibration isolators may be added.
5-594.10
TOP = 3"
ACCESS
SIDE
A
BOTTOM = 1"
Non-Access Side Top
6" 10"
1