Dryer Electric, Gas And Venting - Dexter Laundry T-350 Parts & Service Manual

NOTE: The following considerations must be observed for gas dryer installations where
dry cleaners are installed. The sources of all makeup air and room ventilation air move-
ment to all dryers must be located away from any dry cleaners. This is necessary so that
solvent vapors will not be drawn into the dryer inlet ducts. Dry cleaner solvent vapors will
decompose in contact with an open flame such as the gas flame present in clothes dryers.
The decomposition products are highly corrosive and will cause damage to the dryer ducts
and clothes loads.
Electrical Requirements
The electrical power requirements necessary to operate the unit satisfactorily are listed on the serial plate
located on the back panel of each dryer. The electrical connection should be made to the terminal board
on the rear of the unit using #12 AWG.
It is absolutely necessary that the dryer be grounded to a known ground. Individual circuit breakers for
each dryer and washer are required. Use 15A circuit breakers for the 208 - 240vac dryer. (See Dryer
Specifacation Page for Electric Heated Models)
Gas Requirements
GAS REQUIREMENTS. The complete gas requirements necessary to operate the dryer satisfactorily
arelisted on the serial plate located on the back panel of the dryer and in the specifications section of
thismanual. The inlet gas connection to the unit is 1/2-inch pipe thread. However, the size of the piping
to supply the dryer should be determined by reference to the National Fuel Gas Code ANSI Z223.1A and
consultation with the local gas supplier. An individual gas shutoff valve is recommended for each dryer
and may be required by local code (not supplied). A joint compound resistant to the action of liquefied
petroleum gases should be employed in making pipe connections. A 1/8-inch NPT plugged tapping,
accessible for test gage connection, must be installed immediately upstream of the gas supply connection
to the dryer. A drip tee is provided in the unit gas piping to catch dirt and other foreign articles.All pipe
connections should be checked for leakage with soap solution. Never check with an open flame.For
altitudes above 2,000 feet (610m), it is necessary to derate the BTU input. Contact your local distributor
for instructions. L.P. gas conversion kits are available for this dryer. Contact your local distributor.
CAUTION: The dryer must be disconnected from the gas supply piping system during any pressure
testing of that system. Do not expose the dryer's gas control valve to testing pressure.
Burner Set-Up
All gas burner manifolds should be checked for proper gas pressure while burning. Dryer burners should
be set at 3.5 W.C. for Natural Gas while burner operating.
Exhaust Installation
Exhausting of the dryer should always be planned and constructed so that minimum air restrictions occur.
(Refer to Figure on dryer exhausting). Maximum static back pressure allowed at rear exit of dryer is .3 SBP.
Any restriction due to pipe size or type of installation can cause slow drying time, excessive heat, and
lint build up in system and the room. From an operational standpoint, incorrect or inadequate exhausting
can cause cycling of the high limit thermostat which shuts off the main burners and results in inefficient
drying.
Individual exhausting of the dryer is recommended. All heat, moisture, and lint should be exhausted
outside by attaching a pipe of the proper diameter to the dryer adapter collars and extending it out
through an outside wall. This pipe must be very smooth on the inside, as rough surfaces tend to collect
lint which will eventually clog the ducts and prevent the dryer from exhausting properly. All elbows must
be smooth on the inside. All joints must be made so the exhaust end of one pipe is inside the next one
downstream. The addition of an exhaust pipe tends to reduce the amount of air the blower can exhaust.
This does not affect the dryer operation if held within practical limits. For the most efficient operation, it is
recommended that no more than 14 feet of straight 6" diameter pipe with two right angle elbows be used
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