Midco F400B-33 User Manual

Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS

• Do not try to light any appliance.

• Do not touch any electrical switch;
do not use any phone in your building.

• Immediately phone your gas supplier
from another building. Follow the gas
supplier's instructions.

• If you cannot reach your gas supplier,
call the fire department.

Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.

SSAAFFEETTYY IINNFFOORRMMAATTIIOONN TTEERRMMSS:: The following terms are used to identify hazards, safety precautions or special notations and

have standard meanings throughout this manual. When you see the safety alert symbol and one of the safety information terms, as
shown below, be aware of the hazard potential.

DANGER: Identifies the most serious hazards which will result in severe personal injury or death.
WARNING: Signifies hazards that could result in personal injury or death.
CAUTION: Identifies unsafe practices which would result in minor personal injury or product and property damage.

INSTALLATION AND
SERVICE INSTRUCTIONS

ECONOMITE MODEL F400B-33

Gas Conversion Burner

The ECONOMITE F400B-33 conversion burner with intermittent spark ignited pilot is adaptable to most gas utilization equipment,
including gravity and forced circulation furnaces and boilers. It is particularly recommended for firing horizontal or downdraft equipment
since it needs no draft to maintain a pilot. Power burner design makes it perfectly suited for oil burner replacement, including rooftop
and industrial applications.
In the United States, installation must conform with local codes

or, in the absence of local codes, with Installation of Domestic

Gas Conversion Burners, ANSI Z21.8b-1993, and National
Fuel Gas Code, ANSI Z223.1-1992, or latest edition(s) available

from American National Standard Institute. Further reference
should be made to the recommendation of your fuel supplier.

NOTE: Any additions, changes, or conversions required in order

for the appliance to satisfactorily meet the application needs
must be made by a MIDCO distributor (or other qualified agency)
using factory specified approved parts.

In Canada, installation must conform with local codes or, in the

absence of local codes, with Installation Codes for Gas

Burning Appliances and Equipment, CGA Standard
CAN/CGA1-B149.1 or 2. When the conversion burner is used

on a Forced air Central Furnace, the two yellow and black
warning labels in the literature envelope shall be attached in
accordance with Installation Code, CGa Standard CAN/CGA
1-B149, Clause 5.4.4.4. Further reference should be made to
the recommendation of your fuel supplier.

INST ALLER: Inform and demonstrate to the user

the correct operation and maintenance of this
appliance. Inform the user of the hazards of
storing flammable liquids and vapors in the
vicinity of this appliance and remove such
hazards. Affix this manual adjacent to the
conversion burner.
CODE COMPLIANCE IS THE SOLE
RESPONSIBILITY OF THE INSTALLER.

USER: Retain this manual for future reference. If

other than routine service or maintenance as
described in this manual is required, contact

a qualified service agency. DO NOT
ATTEMPT REPAIRS. An inadvertent service
error could result in a dangerous condition.

WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.

MIDCO International Inc.

4140 WEST VICTORIA STREET, CHICAGO, ILLINOIS 60646 / [phone] FAX: [phone]

PRINTED IN U.S.A.

1296

8470-73

SPECIFICATIONS

Standard burners are shipped as NATURAL gas models.
A kit is available for field conversion to PROPANE gas.

AIR DELIVERY (Approximate Air Delivery

at Zero Draft Maximum Firing)………………...146 SCFM

1

MAXIMUM FIRING RATE2……………………………700 MBH

3

MINIMUM FIRING RATE2…………………………….300 MBH

3

GAS PRESSURE REQUIRED

NATURAL…………………………………5.0" to 14.0" W.C.

PROPANE……………………………….11.0" to 14.0" W.C.
TUBE DIAMETER……………………………………………….4"
TUBE LENGTH………………………………………………….8"
RECOMMENDED COMBUSTION CHAMBER SIZE

700 MBH………………………………15" W x 25" L
ELECTRICAL SUPPLY……120/1/60…10 Amp dedicated
service
FLAME SAFETY………Intermittent proven pilot ignition,

Electronic Safety

1. SCFM=Standard Cubic Feet/Minute.

2. Ratings based on 1000 BTU/Cu. Ft. Natural, 2500
BTU/Cu. Ft. PROPANE at Sea Level. Derate burner
for altitudes over 2,000 feet by 4% for each 1,000
feet above sea level.

3. 1 MBH=1,000 BTU/Hr.
One Gallon of Fuel Oil=140 MBH.

PART 1 INSTALLATION

CAUTION: The ECONOMITE F400B-33 is not
intended for outdoor installation and must be
protected from excessive moisture. Provide
adequate clearance for service and proper operation.

I VENTILA TION

If the former automatic oil burner gave trouble-free
operation, it is probable that the gas utilization equipment
area has sufficient infiltration of air for combustion and
dilution of flue gases. Nevertheless, the area must be

checked:

■■ Open basement or utility areas of normal construction,

without storm windows or tight doors, will generally allow
sufficient air infiltration. However, if the gas utilization

equipment is located in a tight or separate room,
ventilation to an open area as described above will be
required. Install two permanently open grilles, each sized
on the basis of one square inch free area per 1,000 BTU
of the total input rating of all gas utilization equipment in
the combined space. One grille should be located within
12 inches of the ceiling, the other within 12 inches of the
floor.

■■ If the gas utilization equipment is located in an area of

unusually tight construction, or if an exhaust fan, kitchen
ventilation system, clothes dryer and/or fireplace is
installed in the building, provisions must be made for an
outside air supply near the heating appliance area. Install
permanently open grilles sized at not less than one
square inch free area per 4,000 BTU of burner input.
When ventilating through horizontal ducts, grilles should
be sized at not less than one square inch free area per
2,000 BTU of burner input. In any case, the minimum
dimension of rectangular air ducts shall not be less than
3 inches.

■■ In Canada, for detailed ventilation requirements, refer

to standard CAN/CGA 1-B149.1 or .2 and/or local codes.

II PREPARATION OF THE GAS

UTILIZATION EQUIPMENT

■■ Clean the gas utilization equipment, combustion

chamber, heat exchanger interior and flue connections.
Remove all adhering tars, scale, dirt and soot. Inspect for
actual or potential leaks.

■■ Cement all joints, including those in the gas utilization

equipment base and around the door frames, to prevent
leakage into, or out of the combustion chamber.

■■ The access or firing door should open easily to relieve

pressure. If positive latches exist, they should be
modified to permit easy opening; a spring loaded door
holder is recommended.

■■ On all boilers, make certain the pressure relief safety

valve is in good operating condition.

FIGURE 1

Dry Base Boiler with Combustion Chamber

Liner (Warm Air Furnace Construction is Similar)

FIGURE 2

Wet Base Boiler with Unlined

Combustion Chamber

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■■ The Vent Connector shall be as short as possible.

The entire 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 exceed 75% of the height of the chimney above
the connector, or 100% if the Vent Connector is
insulated.

■■ The Vent Connector shall be installed so as to avoid

turns or other construction features which create
excessive resistance to flow of vent gas. It shall be
installed without any dips or sags and shall slope upward
at least 1/4" per foot.

■■ A manually operated damper shall not be placed in the

Vent Connector or chimney of any gas utilization
equipment.

■■ The Vent Connector shall be firmly attached to draft

hood outlets and flue collars. Joints between sections of
connector piping shall be fastened by sheet-metal
screws or other approved means. The Vent Connector
shall be supported for the design and weight of the
material employed to maintain clearance and prevent
physical damage and separation of joints.

■■ A draft hood or a barometric draft regulator shall be

installed in the same room or enclosure as the
equipment in such a manner as to prevent any difference
in the pressure between the hood or regulator and the
combustion air supply (see Figures 3 and 4). In no case
shall the relief opening of the draft hood or barometric
draft regulator be located at a point lower than the top of
the highest flue passage in the equipment.

■■ Gas utilization equipment requiring controlled draft

may be equipped with a listed double acting barometric
draft regulator, if a approved by local codes.

■■ A device which will automatically shut off gas to the

burner in the event of sustained backdraft is required. It
must be of the listed manual reset type and installed and
adjusted by a qualified service technician in accordance
with the manufacturer's instructions.

■■ Refer to the gas utilization equipment manufacturer for

recommended vent connection requirements.

FIGURE 3

Recommended Locations for Draft Hoods

III COMBUSTION CHAMBER

A combustion chamber liner is normally required to

protect non-heat transfer surfaces and to provide a

radiant bed for rapid heat transfer to the primary surfaces

of the heat exchanger. In most cases the existing

combustion chamber liner formerly used for oil burner

can be used, if in good condition.

■■ In the case of wet base boilers, where the entire firing

chamber is comprised of heat exchange surfaces and no

chamber liner was provided for oil firing, a liner is usually

not required for the ECONOMITE. However, a liner or

target wall may be necessary if the firing chamber is

unusually short, in order to avoid flame contact on the

heat exchanger walls or flueways.

■■ If a built up chamber liner is required, use 2,300°F

minimum insulating material.

■■ The burner tube must be sealed air tight into the

combustion chamber opening with refractory material as

shown by Figures 1 and 2.

NOTE: In no case should the burner tube be allowed to

extend into the chamber proper; it must be set flush to 1"

short of the inside surface because high combustion

chamber temperatures will cause premature pilot,

electrode, burner tube and sleeve deterioration.

■■ Special heat resistant alloy extension tubes and

instructions are available for those applications where

the burner tube is too short to reach the combustion

chamber (such as old-fashioned gravity warm air furnace

installations.)

WARNING: BURNER CABINET MUST BE
MOUNTED IN ORIENTATION SHOWN IN FIGURES 1
AND 2. ANY OTHER MOUNTINGS MAY CAUSE A
DANGEROUS CONDITION, AND WILL VOID BURNER
WARRANTY AND AGENCY APPROVALS. NON­STANDARD ARRANGEMENTS MAY BE AVAILABLE
FOR SOME MODELS-CONSULT FACTORY FOR
DETAILS REQUIRED.

■■ Before permanently setting the burner in place, check

that the burner ports and pilot are free of foreign
materials, and also that the electrodes have not been
damaged or displaced. See Figure 7.

IV CHIMNEY, VENT CONNECTOR,

AND DRAFT CONTROL

WARNING: The chimney shall be inspected for
unsafe conditions such as deteriorated masonry and
excessive soot or other blockage or potential
blockage. Installation must conform with local codes
or in the absence of local codes with ANSI Z21.8b­1993 and NFPA, ANSI Z223.1-1992.

WARNING: THE VENT CONNECTOR SHALL NOT
BE CONNECTED TO A CHIMNEY ALREADY
VENTING SOLID FUEL BURNING EQUIPMENT, AN
INCINERATOR OR AN OPEN FIREPLACE.

■■ The Vent Connector shall be made of non-

combustible, corrosion resistant material capable of with­standing the vent gas temperature produced by the gas
utilization equipment and of sufficient thickness to with­stand physical damage.

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