Features And Components; High Limit Swit H; Ele Troni Ignition Control; Barometri Draft Control - A.O. Smith 104 Series Instruction Manual

HIGH LIMIT SWITCH
The dual bulb ontroller ( g 1) ontains the high limit (energy utoff)
sensor The high limit swit h interrupts main burner gas ow should
the water temperature rea h 205 F (96 C)
In the event of high limit swit h operation, the applian e annot be
restarted unless the water temperature is redu ed by at least 20 F
(11 C) and the high limit reset button on front of limit ontrol ( g 1)
is depressed
Continued manual resetting of high limit ontrol, pre eded by higher
than usual water temperature is eviden e of high limit swit h operation
The following is a possible reason for high limit swit h operation
A malfun tion in the thermostati
ontrol valve to remain open ausing water temperature to
ex eed the thermostat setting The water temperature would
ontinue to rise until high limit swit h operation
Conta t your dealer or servi e agent if ontinued high limit swit h
operation o urs
DIGITAL THERMOSTAT
FIGURE 1.
ELECTRONIC IGNITION CONTROL
Ea h heater is equipped with a Honeywell ignition module The
Dire t Spark Ignition Control Module ontrols the ignition
sequen e and gas ontrol operation of the water heater
IGNITION MODULE
FIGURE 2.

FEATURES AND COMPONENTS

ontrols would allow the gas
BAROMETRIC DRAFT CONTROL
The heater is equipped with a double a ting barometri draft
ontrol This ontrol assembly is fa tory adjusted to automati ally
regulate the himney draft imposed on the unit
BAROMETRIC DRAFT CONTROL

COMBUSTION CHAMBER OBSERVATION PORT

The ombustion hamber observation a
above and to the left of the burner A plug lo ated under the
panel, see fig 5, is inserted into the ombustion hamber wall
This plug should not be removed ex ept, in rare ases, when
the ombustion hamber requires leaning or repla ement
UNCRATING
Un rate the heater by removing the outside mat and top lo ator
The shipping pallet must be removed from the unit It may be
possible to simply unbolt the base from the pallet and, with
the help of 2 or more persons, work the unit off the pallet
Some units will be too heavy and will require the use of ja ks
or lifting equipment to safely remove the pallet and move the
unit into position Be areful when moving this heater It will
tip over easily
The heater is shipped with a burner and draft ontrol The
burner and draft ontrol are shipped in separate artons They
should be installed as re eived without any alterations
Dis ard the shipping
appropriate manner
7
FIGURE 3.
ess panel is lo ated
FIGURE 4.
rate and pa kaging artons in an