Dexter Laundry T-750 C4 Installation And Parts & Service Manual page 25

recommended that no more than 20 feet of straight 8" diameter pipe with two right angle elbows be used.
When more than two elbows are used, two feet of straight pipe should be removed for each additional
elbow.
If the exhaust pipe passes through a wall, a metal sleeve of slightly larger diameter should be set in the
wall and the exhaust pipe passed through this sleeve. This practice is required by some local codes and
is recommended in all cases to protect the wall. This type of installation should have a means provided
to prevent rain and high winds from entering the exhaust when the dryer is not in use. A hood with a
hinged damper can be used for this purpose. Another method would be to point the outlet end of the pipe
downward to prevent entrance of wind and rain. In either case, the outlet should be kept clear by at least
24" of any objects which would cause air restrictions.
Never install a protective screen over the exhaust outlet.
When exhausting a dryer straight up through a roof, the overall length of the duct has the same limits as
exhausting through a wall. A rain cap must be placed on top of the exhaust and must be of such a type as
to be free from clogging. The type using a cone shaped "roof" over the pipe is suitable for this application.
Exhausting the dryer into a chimney or under a building is not permitted. In either case there is a danger
of lint buildup which can be highly combustible.
Installation of several dryers where a main discharge duct is necessary, will need the following
considerations for installation.
NOTE: A small diameter duct will restrict air flow, a large diameter duct will reduce air velocity,
both contributing to lint build up, An inspection door should be provided for periodic clean-out of
the main duct.
NOTE: STATIC BACK PRESSURE should be a maximum of 0.3 in. w.c (7.6 mm w.c) at the rear
exhaust outlet of the dryer. If multiple dryers are connected to the common duct, ensure the back
draft damper is installed properly.
NOTE: The following illustration shows the various round main duct diameters to use with
the individual dryer ducts. The main duct can be rectangular or round, provided adequate air
flow is maintained. For each individual cylinder the total exhausting (main discharge duct plus
duct outlet from the dryer) should not exceed the equivalent of 14 feet and two elbows. The
diameter of the main discharge duct at the last dryer must be maintained to exhaust end.
periodic clean out of the main duct.
7. DRYER IGNITION (SOLID STATE IGNITION): The solid-state ignition system lights the main burner gas by spark.
The gas is ignited and burns only when the gas-relay (in the electronic controller) calls for heat. The procedure for
first-time starting of a dryer is as follows.
i. First review and comply with the "Warnings About Use and Operation" found on the inside front cover
of this manual. Be sure electrical power is connected correctly. The dryer must be properly grounded.
Part # 8533-120-001 9/21
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