13
Exhaust/Inlet or both? Both, Inlet and Outlet
Ducting to outside of building or another room? Outside building.
Length of duct from water heater to termination? 20 ft.
Flexible or Rigid ducting? Flexible.
Diameter of ducting used? 8 in. Diameter
Diameter of wall penetrations? 5 in. Diameter
Number of elbows/bends? 3 Total – One on inlet and Two on Outlet
I. Does calculated ducting length exceed maximum allowable table?
a.
20 ft. (Outlet duct length)
b.
10 ft. (1 rigid elbow and 1 bend on outlet)
c.
20 ft. (reduced diameter termination outlet)
d.
20 ft. (Inlet duct length)
e.
5 ft. (1 Bend on inlet)
f.
20 ft. (reduced diameter termination inlet)
g. Total = 20+10+20+20+5+20 = 95 ft.
Using flexible 8 in. diameter duct, the maximum duct length allowed is 125
ft.; therefore, because 95 ft. is less than 125 ft., this is an acceptable ducting
configuration.
Accesory Kits SP20887 (2 Kits), SP20889 (2 Kits) and SP20890 (1 Kit) should
be purchased for this installation.
Ducting Example:
Flex Duct secured and
sealed with Duct tie
(2 places on Inlet)
(1 place on Outlet
to secure Flex Duct to unit flange)
UL Certified
terminations
Rigid Adjustable
Elbow
Flex Duct
Insulation Extented
over Rigid Ducting
and secured with
Duct Tie
Rigid Duct
secured with 4
screws to unit
flange
Cold
Air Exhaust
HVAC tape used
to seal Reducer
and termination joints
6” Clearance
for filter
8” to 5”
Duct Reducers
Air Inlet
Flex Duct Insulation
extended over reducers
and secured with Duct tie
8” Insulated
Flex Duct
8” Insulated
Flex Duct
NOTICE:
These
seven questions
should be answered
to ensure correct duct
configuration.
See Ducting Example.
Once the duct terminal
location has been
determined, make a hole
through the exterior wall
to accommodate the UL
Certified Termination.
Termination must exit
exterior wall horizontally
only.
Complete rest of the
duct pipe installation to
the water heater’s duct
connector fitting.
If necessary, support
horizontal run as
previously mentioned.
Horizontal Duct
Installation
