Midco 400-33 Parts List

Replacement Parts

List

Economite Model 400-33

This burner has been manufactured since 1961 and has been relatively unchanged except
for various pilot styles described on page 4. Pilot styles can be determined by the double
digit suffix following "Model 400" on the rating plate.

. Serial number discontinued April 1969 with 94,000.
. Date coding started April 1969 with 1769 (17th week, 1969).

• Pressure tap moved from "B" cock assembly to pilot solenoid February 26, 1986 (date
code 986).

• Motors featuring permanently lubricated bearings used for the first time January, 1987
(date code 487).

• Honeywell R4795A Flame Safeguards superseded by Honeywell RM7895 Flame
Safeguards November, 1993. R4795AFlame Safeguard is not available.

Manuals:
400-33 Installation and Service Manual 8449-84 for 400-33.

IMPORTANT: Availability of parts as well as specifications are subject to change without

notice. Please consult factory for item availability.

• Construction required Dual Main Valves (UL 795 Requirement) April 1, 1994 (date code

1394)

• Maxitrol phased out their RV10 and RV60 Regulators February and March 1992 and
replaced them with Models RV12 and RV61. Refer to notes 5 and 6 page 2.

802

8472 01

Printed in USA

Midco®International Inc.

4140 West Victoria Street
Chicago, Illinois 60646
tel [phone]
fax [phone]
web www.midcointernational.com
[e-mail]

Quality Designed for Proven Performance

For manufacturing dates and manual availability,
refer to historical data below and on page 2.

Supersedes EC88, EC131

400-33

Economite 400-33 Exploded View

2

NOTES

1. See MAMMOTH INDUSTRIES, page 3.

2. Some applications, usually O.E.M., require the use of more than one extension. Determine the exact number in your ECONOMITE
before ordering.

3. Motors featuring permanently lubricated ball bearings were used for the first time in production January 1987 (date code 487).

4. 5" and 15" Blower Housing and Blast Tube Assemblies are NOT available. A 5" assembly can be fabricated by hack sawing 4" off of a 9"
assembly. A15" assembly can be made by assembling a 9" assembly with 2020500 (8" long Accessory Blast Tube Extension).

5. Maxitrol and General Controls Pilot Regulators have been used interchangeably. For exact replacement, determine the model used in
your ECONOMITE before ordering. If regulating PROPANE, select 8400-00 (Maxitrol RV-12), as the RV-12 responds better to
PROPANE regulation.

6. 3/4" NPT and 1" NPT Main Regulators have been used interchangeably. Determine the size used in your ECONOMITE before ordering.

7. 3/4" NPT and 1" NPT Main Automatic Valves have been used interchangeably. Determine the size used in your ECONOMITE before
ordering. Several brands have been used, depending on price and availability. MIDCO will provide whatever is currently in stock. If you
desire exact replacement, obtain locally. NOTE: MIDCO stocks only complete valve assemblies. Obtain operator heads or bodies locally.

8. When replacing Fluid Power Valves, obtain exact valve number and brand from valve rating plate, as well as the bill of material number
from the ECONOMITE rating plate. Contact MIDCO for price and availability.

9. Contact MIDCO for availability of early EC manuals.

10. WARNING: Explosion hazard. Can cause serious injury or death. This device can malfunction if it gets wet. Never try to use a

device that has been wet -- replace it.

11. Honeywell R4795A Flame Safeguards were phased out of production November, 1993. Replaced by Honeywell RM7895 Flame
Safeguards. Determine which version is required before ordering.

• REFER TO LISTING

LAYOUT MAYNOT BE AS SHOWN

AVOID ERROR IN PARTS SELECTION. When ordering use complete MIDCO Part Number and Description.
Furnish burner model number, bill of material number and date code (if available) from rating plate.

8402-00

Economite 400-33 Parts List

3981-0014" Diameter Stainless Sleeve
4904-45 Quadrant -- Air Shutter Adjustment
4905-15 Air Shutter -- Internal
4912-10 Motor Conduit with hardware
4916-00 Motor Mounting Ring less rubber mounts & nuts
4917-00 Main Orifice Holder
4918-01 Orifice Elbow (3/4" NPT)
4919-00 Blower Wheel with Centrifugal Actuator and Disc
4919-90 Centrifugal Actuator Disc
4922-90 Primary Air Shutter Kit
4924-10 Inlet Side Plate
4944-01 Main Spud 11/32" Drill (.343) minimum capacity -

NATURAL

4944-02 Main Spud 25/64" Drill (.390) maximum capacity -

NATURAL

4944-03 Main Spud #21 Drill (.159) minimum capacity --

PROPANE -- drill for desired capacity per manual

4944-10

2

Main Spud Extension
4959-05 External Pilot Air Tube Kit
5201-00 1/2" sq. Pass Through for 1/4" Tube Fitting (gas

line)
5201-10 1/2" sq. Pass Through for 5/16" Tube Fitting (air

line)
5201-90* 400 Ser Rub Seal Strp
5202-04 Pilot Spud #68 (.031) Drill was #66 (.033) --

NATURAL and PROPANE
5211-01 Motor, Wheel, Side Plate and Cage Assembly

120/1/60
5216-50

3

Motor less mounting ring and rubber mounts

120/1/60 (Universal Electric AAP026N#,

AA2G014#, JA2P182N#, JB2P048N#; Fasco

7163-7511)
5225-26

4

Blower Housing and Burner Tube Assembly -- 9"
5225-28

1

* Blower Housing and Burner Tube Assembly --

6 3/8" (Mammoth Industries)
5234-40 Flamerod Gland Nut
5234-50 Flamerod Assembly
5249-01 Pilot Air Baffle
5249-32 Spark Rod Assembly
5250-00 Pilot Tip with Cone less Insulators, Rods, Tem-

flex and Baffle
5253-01 Pilot Assembly with Insulators, Rods, Temflex

and Baffle
5253-10 PVC Tubing — 7/16" I.D. x 2" long
5269-05 Blower Interlock Switch (MICRO Switch) with

Bracket (replaces early ACRO Switch) -- if only

MICRO Switch is desired order 8423-16
5278-00 3 Rubber Mounts and Nuts
5939-01 Flamerod Wire -- 5" through 9" Burner Tube
5939-02 Flamerod Wire -- 15" Burner Tube

Part # Description

Part # Description

8400-0051/8" NPT Pilot Regulator -- 0.5" PSI maximum

inlet (Maxitrol RV10, RV12, RV12LT)

8400-05

5

1/8" NPT Pilot Regulator -- 1/2 PSI maximum

inlet (General Controls V300)
8401-00 1/8" NPT Pilot "B" Cock
8402-00 1/8" NPT Pilot Solenoid 120/1/60
8416-01

6

3/4" NPT Main Gas Pressure Regulator --

NATURAL (Maxitrol RV53)
8416-33

6

1" NPT Main (Gas Pressure Regulator --

NATURAL (Maxitrol RV60, RV61)
8418-01

7,8

3/4" NPT Main Automatic Valve 120/1/60
8418-03

7,8

1" NPT Main Automatic Valve 120/1/60
8423-16 Blower Interlock Switch (MICRO BZ-2RQ174-A2)
8428-07

11,

* Honeywell Q270 Mounting Base -- use RA890

or R4795
8428-24

10,11,

* Honeywell R7289 Plug-In Rectification Amplifier

(use with R4795A)
8428-26

10,11,

*Honeywell ST71 Plug-In Prepurge Timer--30

seconds (use with R4795A)
8429-16

10,11

Subbase for Flame Safeguard (M-HQ7800B)

8429-19

10,11

RM7895A Controller

8429-22

10,11

30-Second Purge Timing Card (Honeywell

ST7800A1039)
8429-25

10,11

90-Second Purge Timing Card ( Honeywell

ST7800A1062)
8429-27

10,11

Rectification Amplifier (Honeywell R7847A1033)
8429-28* Keyboard Display
8432-09* 1.512 OD x 1.234 ID O-Ring
8433-06* Pilot Spud (.021) -- NATURAL(3N4-021, Y90AA-

3221)

8433-08* Pilot Spud (.012) -- PROPANE (2-14L12, Y90AA-

4212)
8447-22* Honeywell Spark Generator
8449-84

9

* Installation and Service Manual
8450-21 Orifice Holder Sealing Gasket
8451-06 Spark Rod Insulator Sleeve
8484-72 Heyco Strain Relief (SR-4K-1) -- Flamerod Wire
8484-75 Heyco Strain Relief (SR-11-2) -- Spark Rod Wire
8484-78 Heyco Snap Bushing (B-875-750) -- Control Box
8502-05 Spark Cable -- 15" Burner Tube
8502-06 Spark Cable -- 5" through 9" Burner Tube
2020100* 4" Mounting Flange
2030300* Kit to convert NATURAL burner to PROPANE --

includes minimum spud to be drilled per manual,
Main Regulator Spring, Instructions, etcetera

2020400* 4" long Accessory Blast Tube Extension (Service

Bulletin 8448-94 is included)

2020500* 8" long Accessory Blast Tube Extension (Service

Bulletin 8448-94 is included)

* NOT SHOWN

MAMMOTH INDUSTRIES

A flame spreader or target, welded to MIDCO's 4" diameter Stainless Sleeve, was manufactured at MIDCO and supplied to
Mammoth Industries (first production October 1962). Mammoth Industries ultimately manufactured the spreader themselves.
Contact Mammoth Industries for flame spreader replacements.

Early (1962 through 1965) Mammoth Inverted Blower Housing and 6 3/8" Burner Tube Assembly included a welded mount­ing flange. The welded Mammoth flange is no longer available. For field substitution, order 5225-28 Blower Housing and
Burner Tube Assembly and 2020100 4" Accessory Mounting Flange.

3

Midco International Inc. 4140 West Victoria Street * Chicago, Illinois 60646 802

tel [phone] * fax [phone] * web www.midcointernational.com email [e-mail] 8472 01

Printed in USA

4

PILOTS

The current MIDCO -33 Spark Ignited Pilot has evolved through a number of designs since MIDCO built its first 400 Series
burner with spark ignition and flamerod electronic safety. Listed below are brief descriptions of each design, approximate pro­duction dates and parts availability. Many Burners have been converted to the current production -33 Pilot.

IMPORTANT: Frequently the serviceman fails to adequately remark the rating plate with the new pilot designation

when a burner is converted. For example, when a Model 400-03 burner is converted to a -33 pilot, the
rating plate should be modified to read 400-33. It is critical that you confirm that the rating plate reflects the
actual pilot designation before ordering parts.

Production dates overlap considerably, as some O.E.M. accounts chose not to change pilot models until their next A.G. A. or
U.L. recertification review.

First Production: 1961
Discontinued: November 1964

Available Parts:
8433-06 Pilot Spud .021 NATURAL
8433-08 Pilot Spud .012 PROPANE

First Production: October 1962
Discontinued: Date unknown

Used primarily on burners supplied to
Mammoth Industries

Available Parts:
8433-04 Pilot Spud .023 NATURAL

First Production: April 1963
Discontinued: January 1970

Available Parts:
8433-06* Pilot Spud .021 NATURAL
8433-08 Pilot Spud .012 PROPANE

*In rooftop or high draft (particularly I.D. fan)
installations, install 8433-04 Pilot Spud .023 NATURAL

First Production: March 1965
Discontinued: October 1966

NO PARTS AVAILABLE FOR THIS PILOT

First Production: October 1966
ALL PARTS ARE A VAILABLE FOR THIS

PILOT -- REFER TO LISTING

TYPE -03 PILOT

Identifiable Feature:
Hook Shaped Ground Rod

TYPE M3 PILOT

Identifiable Feature:
Formed Baffle

TYPE -13 PILOT

Identifiable Feature:
2 Flat Baffles

TYPE -23 PILOT

TYPE -33 PILOT

Identifiable Feature:
Cast Iron Body