Specifications

FLUEING
29
FLUE LENGTHS
Maximum Flue Length
The system will not operate if there is excessive restriction (pressure drop) in the flueing system.
The maximum length of a secondary flue, with no bends, between the water heater and the flue terminal is
13.5 m.
To determine the maximum length of flue for an installation, reduce the maximum length of 13.5 m:
 by 1.5 m for every 90° bend, and
 by 0.75 m for every 45° bend.
A secondary flue may have a combination of 90° bends and 45° bends.
Horizontal runs of flue must be installed with a gradient of 20 mm per metre of horizontal run.
Note: Ensure the seam of the inner flue in horizontal runs is at the top of the installation.
Minimum Flue Length
The minimum horizontal flue distance which may be used is 300 mm, provided:
one 90° Bend is connected to the flue outlet of the water heater, and
the Horizontal Flue Terminal is connected to the 90° Bend.
FLUE CONDENSATE
Condensate from the combustion gases may
form in the flue. The flue outlet assembly at
the top of the water heater incorporates a
condensate drain spigot to allow for draining of
this condensate.
This spigot is covered by a rubber cap held in
position by a clamp. For certain types of
installations, it will be necessary to remove the
clamp and cap and install a Condensate Trap
(PN 295139) and drain line.
The Condensate Trap must be filled with water
prior to the operation of the water heater.
Refer to “Condensate Trap and Condensate
Drain Line” on page 30.
Draining the Condensate
A Condensate Trap and drain line must be installed under the following conditions in order to prevent
condensate from draining back into the water heater:
Where vertical sections exceeding 2 m are incorporated in a horizontally terminating flue system.
Where the flue terminates vertically.
Where there is a horizontal run of flue between two bends and the bend closest to the flue terminal is
orientated upward.
 This horizontal run of flue must have a gradient upward to the flue terminal. Condensate will drain
back toward the water heater.
Failure to install a Condensate Trap and drain line could allow acidic flue gas condensate to enter into the
water heater flue-way, causing premature failure of the water heater. Any resultant faults will not be covered
by the Rheem warranty.
Note: A horizontal run of flue connecting directly to a Horizontal Flue Terminal must have a gradient
downward to the flue terminal. Condensate will drain from the flue terminal.
CONDENSATE
SPIGOT
CONDENSATE SPIGOT LOCATION
CFWH 627 INDOOR MODELS
SK7166-5 REV AD 1/12
REMOVE
CLIP
REMOVE
RUBBER CAP
condensate drain spigot