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-7-

 Check for high or low pilot gas pressure.  Pilot gas pressure

tap is located in tee fitting in pilot gas line near bottom of back
plate.  If over 7.0" W.C. with burner on, the size of pilot flame
should be reduced to increase heat on the thermocouple.  Pilot
gas adjustment screw (needle valve) is located on the inlet end
of combination gas valve body and is factory set full open.
Remove plug for access and turn clockwise to reduce flow
(pressure). 

CAUTION: If there is more than a 1.0"W.C. differential

between STANDBY inlet pressure when all appliances are
OFF, and the inlet pressure when the burner and all other
appliances are ON, a 1Ú8 inch Maxitrol RV12 (or equal)
pressure regulator must be installed in the pilot gas line.
With the adjustment screw wide open, set the pilot flame
gas pressure at 4.0"W.C. for NATURAL gas, 8.0"W.C. for
PROPANE.

 Examine the thermocouple.  If there is any serious corrosion

or loss of metal at the tip, replace the thermocouple.

 The efficiency of the thermocouple and pilotstat safety

control of the combination valve can be determined by timing
the safety shut-off.  With power to the burner shut off and with
the combustion chamber cool, allow the pilot to operate at
least five minutes.  Then turn off the pilot and time the period
until a click is heard from the pilotstat safety control in the
Combination Valve.  If less than 30 seconds or exceeds 3
minutes, the thermocouple, pilot flame adjustment or the
pilotstat safety control is faulty and the entire Combination
Valve must be replaced.

 An accurate check of the thermocouple and pilot flame

adjustment can be made with a millivoltmeter.  The
thermocouple, when heated by the pilot, should develop at
least 15 millivolts minimum to 25 millivolts maximum open
circuit (thermocouple disconnected from pilotstat safety control
of combination valve).  If millivolt reading is above maximum,
readjust pilot gas input slightly to reduce voltage.  Check
results with blower motor on and off.

 Tests to isolate thermocouple and/or pilotstat safety control

problems can be conducted under closed circuit conditions
(thermocouple connected to valve through an 

adaptor

 that

provides for connecting the millivoltmeter).  If the thermocouple
does not develop at least 7 millivolts when the pilot flame is
properly adjusted, it is defective.  If the valve does not hold in
with 7 millivolts, the pilotstat safety control section is defective
and entire valve must be replaced.

 If the thermocouple develops 15 millivolts minimum open

circuit and 7 millivolts minimum closed circuit but drop out
timing is under 30 seconds or exceeds 3 minutes, the pilotstat
safety control section is defective and entire valve must be
replaced.

WARNING:   When  reassembling  burner,  make  sure

that the manifold slide plate is positioned in its holder and
that  the  main spud is inserted into the end of nozzle (see
Figures 5 and 6).

X

BLOWER SHELF ASSEMBLY

The shelf assembly including the blower and motor, motor
relay, low voltage transformer and terminal board can be
withdrawn as a unit after the back plate is removed and
external wiring is disconnected.

 Cleaning of the blower wheel is usually the only service

required.  Need for cleaning is indicated if the air inlet slots in
the burner housing show an accumulation of dust and lint, or if
the character of the flame  -- long, hazy and yellow (sooty) --
indicates a deficiency of air.  Motor air cooling vents should
also be cleaned at this time.

 If the motor must be replaced, remove the blower wheel

first and remove the retainer clips at the rubber motor
grommets, pull the motor out of keyhole brackets.  Remount
in reverse order noting that brass flanges of rubber motor
mounts are located against motor.  Do not omit the three
clips.  Position blower wheel on motor shaft to provide 1/8
inch clearance between blower inlet opening and blower
wheel ring.

 Shelf gaskets are installed on the inside of the back cover

and inside of the front of the burner cabinet.  Be sure they are
in place when reinstalling the shelf assembly, otherwise
blower air will be lost and combustion could be affected.

XI

COMBINATION GAS VALVE

The 24 volt combination valve serves five functions:

1.  Main manual and pilot gas shut-off,
2.  Manifold gas pressure regulation,
3.  Pilot gas input adjustment,
4. Automatic electric main gas valve; single seated on 

 Model E20B, double seated (redundant) on E20BP 
 Models, and

5.  Pilotstat safety control.

A pilot filter is also included.

 For manual control the manual gas cock knob is turned full

ON

 or full 

OFF

.  The dial has to be depressed to be turned in

one direction, but it depends on the manufacturer of the valve
whether it is in the 

ON

 or 

OFF

 position.

 Refer to Section IX for pilot adjustment.

 The combination valve gas pressure regulator has an outlet

pressure setting range of 2.0" to 4.0" W.C. and is factory set
for 2.0" W.C.  Manifold gas pressure tap is located on the
outlet end of the combination gas valve body.

 If pressure adjustment is required for setting capacity,

remove regulator cap for access to slotted adjustment screw.
Turning of adjustment screw counterclockwise reduces
pressure; clockwise increases pressure.  Do not adjust past
point where no change in pressure is noted. 

 

NOTE:

  Pressure setting can only be made with burner run-

ning and gas on.

 

CAUTION:    If   gas  supply  pressure  is   below   its

specified range during adjustment, an overfire condition
could result when pressure returns to normal, particularly
if the regulator adjustment screw is bottomed out.  AL-
WAYS confirm that at least the minimum rated gas pres-
sure is being supplied to the burner during regulator ad-
justments, and NEVER bottom out regulator screw.

 If the pressure regulator fails to maintain a constant

manifold gas pressure 0.1" W.C., with an inlet
pressure within the specified 5"-14" W.C., the regulator
section of the valve is defective and entire valve must be
replaced.

 The pilotstat safety control may be suspect if frequent "pilot

outages" occur.  Refer to Section IX to isolate the problem.

 If, on a call for heat, the main burner fails to operate even

though the pilot is burning and the motor is running, failure of
the electric valve operator(s) may be indicated.  Refer to the
TROUBLE CHART for further information.

 If leakage through the valve occurs on standby, as

evidenced by the presence of any flame other than pilot, the
entire valve must be replaced.

CAUTION:  If the combination valve has been moved

or replaced,  soap  bubble  test  for  leaks  with the burner
running.

Содержание Economite E20B

Страница 1: ...ot touch any electrical switch do not use any phone in your building Immediately call your gas supplier from a neighbor s phone Follow the gas supplier s instructions If you cannot reach your gas supp...

Страница 2: ...ir supply near the gas utilization equipment area Install permanently open grilles sized at not less than one square inch free area per 4 000 BTU of total input When ventilating through horizontal duc...

Страница 3: ...ntire length shall be readily accessible for inspection cleaning and replacement The length of horizontal uninsulated Vent Connector between chimney and a single gas utilization equipment shall not ex...

Страница 4: ...I IR R R RI I I IN N N NG G G G A A A AN N N ND D D D C C C CO O O OM M M MP P P PO O O ON N N NE E E EN N N NT T T TS S S S B B B BY Y Y Y M M M MI I I ID D D DC C C CO O O O CAUTION Do not add any...

Страница 5: ...rfire pressure at sea level TABLE 3 Main Gas Spud Capacity and Preliminary Gas and Air Settings WARNING Reposition the air shutter for the maximum firing rate of the selected spud capacity range Do no...

Страница 6: ...g rate for NATURAL gas Accurately time test dial for the number of seconds for one revolution and use the following formula All other gas utilization equipment must be off For PROPANE gas consult your...

Страница 7: ...sually the only service required Need for cleaning is indicated if the air inlet slots in the burner housing show an accumulation of dust and lint or if the character of the flame long hazy and yellow...

Страница 8: ...replacing a component ELECTRICAL AND FLAME CHECKS MUST BE MADE IN THE ORDER LISTED I PILOT WILL NOT LIGHT A Manual gas cock knob on combination valve is not depressed in the PILOT position B Main Man...

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