Mr. Heater MHU 45 Operating Instructions And Owner's Manual page 8

5. Vent termination must be a minimum of 4' (1.2m) below or 4'
(1.2m) horizontally from any soffit vent or under-eave vent.
6. Vent must be a minimum of 6' from an inside corner formed
by two exterior walls. If possible, leave a 10' clearance.
7. Vent termination must be a minimum of 10' (3m) from any
forced air inlet (includes fresh air inlet for other appliances,
such as a dryer).
8. When termination is routed through an exterior combustible
wall the vent must be supported using a listed clearance
thimble. Where local authorities permit, a single section of
type B-1 vent pipe may be used as an alternative to the
thimble. When using a type B-1 vent termination use the
clearances specified by the vent manufacturer. Seal the
connection between the single wall and double wall pipes and
the annular space of the double wall pipe as shown in figure
2. Inside edge of vent termination tee must be at least 12
inches from outside wall as shown in figure 3.
9. For horizontal venting, the vent pipe shall be supported with
hangers no more than 3ft. (1m) apart to prevent movement
after installation.
D – HORIZONTAL VENTING – COMMERCIAL
1. Horizontal commercial installations are for buildings which are
not attached to living spaces. The vent may be single wall
vent material installed according to the sections
Venting A - General Recommendations and
Requirements and C - Horizontal Venting General and D
- Horizontal Venting - Commercial. Refer to figure 3.
2. The vent pipe diameter for horizontal commercial
installations shall be 3" (76mm) on 45 units. In all cases, a flue
MAY BE SINGLE WALL (26 GSG) GALV. OR EQUIV. STAINLESS STEEL SEALED ACCORDING TO
THESE INSTALLATION INSTRUCTONS. SLOPE: + 1/4 INCH FOR 1 FOOT RUN MINUMUM.
INDUCED DRAFT BLOWER
NOTE - MINIMUM HORIZONTAL LENGHT 3 FT. (914MM),
NOT INCLUDING CAP FOR TERMINATION. REFER TO
TABLE 2 FOR MAXIMUM LENGTH AND NUMBER OF
ELBOWS.
04/07 Revision B #60016
CONDENSATE DRAIN THROUGH TEE PIPE AND DRAIN LOOP
UPWARD SLOPE ON HORIZONTAL VENT-COMMERCIAL INSTALLATION
FLUE TRANSITION
DRAIN LOOP WITH WATER
TRAP (TO CONDENSATE DRAIN)
COMMON VENTING NOT ALLOWED WHEN HORIZONTALLY VENTING THE UNIT HEATER
Enerco | Compact Unit Heater
transition piece (supplied) is required to fit over the outlet of
the induced draft assembly on the appliance.
3. Refer to table 2 for maximum vent connector lengths.
4. Select a wall termination point that will maintain ¼" rise per
foot slope of horizontal run of vent pipe. The vent may be
single wall material minimum 26 GSG (0.46mm) galvanized
steel or equivalent grade stainless steel. Seal single wall vent
material according to the section A - General
Recommendations and Requirements.
5. For upward sloped vent a condensate tee and drain must be
installed within the first 5' (1.5m) from the unit heater to
protect the appliance. If a flexible condensate drain line is
used, the drain line must include a loop entering the structure.
If the unit is shut down for an extended period of time and
will be exposed to sub-freezing temperatures, the condensate
may freeze.
E – HORIZONTAL VENTING – RESIDENTIAL
1. For horizontal residential installations these units are certified
as Category I appliances. The vent may be single wall
material minimum 26 GSG (0.46mm) galvanized steel or
equivalent grade stainless steel. Venting A - General
Recommendations and Requirements and C - Horizontal
Venting General and E - Horizontal Venting - Residential.
Refer to figure 6.
2. The vent pipe diameter for horizontal residential installations
shall be 4" (100mm) on 45 units. A standard vent transition is
required at unit in addition to the transition supplied with the
unit.
3. The maximum vent length is 5' (1.5m) plus one 90-degree
elbow. Minimum length is 3' (.91m).
(PROVIDED)
LISTED THIMBLE
THROUGH COMBUSTIBLE
WALL
FIGURE 3
8
Operating Instructions and Owner's Manual
12 INCHES MIN.
(30.5 CM)
VENT TERMINATION
CAP
12" (30.5 CM)
MINIMUM ABOVE ALL
HIGHEST SNOWFALL