Midmark M7-2 Service manual

®

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SpeedClave Steam Sterilizers

Model Numbers:

M7 M7

-011 thru -016

-020 thru -022

Serial Number Prefixes:

MH, MJ, MK, ML, MM, MN, V

V

Ser vice and

Par ts Manual

SF-1855 Part No. 004-0454-00 Rev. D (4/1/08)

FOR USE BY MIDMARK TRAINED TECHNICIANS ONLY

GENERAL INFORMATION

Symbols ....................................i

Ordering Parts .......................... i

Model / Serial Number

Location .................................. i

Weights, Dimensions,

Electrical Specifications ....... ii

Model Identification /

Compliance Chart .................. iii

Special Tools ............................ iv

Warranty Information............... iv

General Information

ACCESS PROCEDURES

Removing & Installing:

Covers / Panels ........................ C-2

Tray Plate / Rack ...................... C-3

Draining / Filling Reservoir .....C-4

Section C

WIRING DIAGRAMS & SCHEMATICS

115 VAC models

M7 (-011 / -013 / -014 / -015) ........

M7 (-020 / -022) ............................

:

D-2 D-3

OPERATION & TROUBLESHOOTING

Electrical System:

M7 (-011 thru -016) .......................

M7 (-020 thru -022) .......................

Filling the Chamber ................. A-8

Heat-Up / Sterilization.............. A-14

Section A

Venting the Chamber ............... A-20

A-2 A-4

230 VAC models

M7 (-012 / -016) ............................

Section D

M7 (-021) ......................................

EXPLODED VIEWS / PARTS LISTS

M7 M7

TESTING & REPAIR

Checking for

Pressure Leaks ...................... B-2

Fuse........................................... B-3

Bellows ..................................... B-4

Fill / Vent Valve:

Section B

Table Of Contents

Manual ..........................................

Electronic ......................................

Temperature Regulator Assy .. B-12

Heating Element ....................... B-18

Overheat Thermostats ............. B-22

Pressure Relief Valve ............... B-25

Timer ......................................... B-26

Timer Buzzer ............................ B-30

Temperature Gauge ................. B-31

Door Assembly......................... B-32

Reservoir Tank.......................... B-34

Chamber Assembly ................. B-36

B-6 B-8

Section E

:

(-011 thru -016) ....................

(-020 thru -022)

:................... E-3

D-4 D-5

E-2

Symbols

Go To Table Of Contents

Caution

Indicates a potentially hazardous situation which could result in injury if not avoided.

Equipment Alert

Indicates a potentially hazardous situation which could result in equipment damage if not avoided.

Note

Amplifies a procedure, practice, or condition.

Indicates that the component the check mark appears beside should be tested before replacing it. In Section A, test the components in the order indicated. (ex.

1st

33

3

33

then,

33

3

33

Refer to Section B for component testing procedures.

2nd

)

33

3

33

Ordering Parts

General Information

Model / Serial Number Location

R

Serial Number

(all models)

Model & Serial Number

The following information is required when ordering parts:

• Serial number & model number

• Part number for desired part.

[Refer to Section E: Exploded Views / Parts Lists]

Non-warranty parts orders may be faxed to Midmark using the Fax Order Form in the back of this manual.

For warranty parts orders, call Midmark's Technical Service Department with the required information.

Hours: 8:00 am until 5:00 pm EST [Monday - Friday] Phone: 1-(800)-Midmark

General Information

M7 (-011 thru -016)

Location: bottom of unit

M7 (-020 thru -022)

Location: back of unit

i

General Information

Go To Table Of Contents

Weights, Dimensions, Electrical Specifications

ATTENTION

A separate (dedicated) electrical circuit is recommended for all models. Do not connect to a circuit with other devices, unless the circuit is rated for the additional load.

R

A

M7 (-011 thru -016)

Dimensions

Height Width Depth

Chamber Size: ..................................... Diameter: 7.5 in. (19 cm)

Depth: 14.25 in. (36.2 cm)

Shipping Carton:

(Length x Width x Height) ..................

(61 cm x 40.6 cm x 40.6 cm)

Weight:

Shipping Weight ................................. 39 lbs (17.7 kg)

w/reservoir empty .............................. 30 lbs (13.6 kg)

w/reservoir full ................................... 41.8 lbs (19 kg)

Reservoir Capacity: ............................ Approx. 1.3 gallon (4.9 liters)

at FULL mark

Pressure Relief Valve:

opens at approximately: ....................

Electrical Requirements: ....................

Compliance Chart]

Power Consumption:

100 VAC models ................................

115 VAC models ................................

230 VAC models ................................

[Refer to illustration]:

(A) ...........................................

(B) ............................................

(C) ...........................................

12.8 in. (32.5 cm)

13.5 in. (34.3 cm)

18.1 in. (46 cm)

24 in. x 16 in. x 16 in.

34 psi (234 kPa)

[See Model Identification /

1150 watts, 12 amps @ 100 VAC 1150 watts, 10 amps @ 120 VAC 1150 watts, 5 amps @ 240 VAC

B

C

M7 (-020 thru -022)

Dimensions

Height Width Depth

Chamber Size: ..................................... Diameter: 7.5 in. (19 cm)

Depth: 14.25 in. (36.2 cm)

Shipping Carton:

(Length x Width x Height) ..................

(61 cm x 40.6 cm x 40.6 cm)

Weight:

Shipping Weight ................................. 39 lbs (17.7 kg)

w/reservoir empty .............................. 30 lbs (13.6 kg)

w/reservoir full ................................... 41.8 lbs (19 kg)

Reservoir Capacity: ............................ Approx. 1.3 gallon (4.9 liters)

at FULL mark

Pressure Relief Valve:

opens at approximately: ....................

Electrical Requirements: ....................

Compliance Chart]

Power Consumption:

115 VAC models ................................

230 VAC models ................................

[Refer to illustration]:

(A) ...........................................

(B) ............................................

(C) ...........................................

13 in. (33 cm) 14 in. (35.6 cm) 19 in. (48.3 cm)

24 in. x 16 in. x 16 in.

34 psi (234 kPa)

[See Model Identification /

1300 watts, 10 amps @ 115 VAC 1300 watts, 5 amps @ 230 VAC

ii

Rev.12/04

Fuse

(back of unit)

115 VAC models ................................

230 VAC models ................................

:

12 amp, 250 V, Fast-Acting, 1/4" x 1-1/4" 8 amp, 250 V, Fast-Acting, 5 x 20 mm

Model Identification / Compliance Chart

Go To Table Of Contents

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General Information

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310-7M

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iii

General Information

Go To Table Of Contents

Special Tools

This table lists all special tools needed to diagnose and repair the sterilizer.

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Warranty Information

SCOPE OF WARRANTY

Midmark Corporation (“Midmark”) warrants to the original purchaser its new Alternate Care products and components (except for components not warranted under “Exclusions”) manufactured by Midmark to be free from defects in material and workmanship under normal use and service. Midmark’s obligation under this warranty is limited to the repair or replacement, at Midmark’s option, of the parts or the products the defects of which are reported to Midmark within the applicable warranty period and which, upon examination by Midmark, prove to be defective.

APPLICABLE WARRANTY PERIOD

The applicable warranty period, measured from the date of delivery to the original user, shall be one (1) year for all warranted products and components.

EXCLUSIONS

This warranty does not cover and Midmark shall not be liable for the following: (1) repairs and replacements because of misuse, abuse, negligence, alteration, accident, freight damage, or tampering; (2) products which are not installed, used, and properly cleaned as required in the Midmark “Installation” and or “Installation / Operation Manual for this applicable product. (3) products considered to be of a consumable nature; (4) accessories or parts not manufactured by Midmark; (5) charges by anyone for adjustments, repairs, replacement parts, installation, or other work performed upon or in connection with such products which is not expressly authorized in writing in advance by Midmark.

EXCLUSIVE REMEDY

Midmark’s only obligation under this warranty is the repair or replacement of defective parts. Midmark shall not be liable for any direct, special, indirect, incidental, exemplary, or consequen tial damages or delay, including, but not limited to, damages for loss of profits or loss of use.

NO AUTHORIZATION

No person or firm is authorized to create for Midmark any other obligation or liability in connection with the products.

ADDITIONAL INFORMATION

Failure to follow the guidelines listed below will void the warranty and/or render the table unsafe for use.

• If a malfunction is detected, do not use the table

until necessary repairs are made.

• Do not attempt to disassemble table, replace

components, or perform adjustments unless you are a Midmark authorized service technician.

• Do not use another manufacturer's parts to replace

malfunctioning components. Use only Midmark replacement parts

THIS WARRANTY IS MIDMARK’S ONLY WARRANTY AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED. MIDMARK MAKES NO IMPLIED WARRANTIES OF ANY KIND INCLUDING ANY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. THIS WARRANTY IS LIMITED TO THE REPAIR OR REPLACEMENT OF DEFECTIVE PARTS.

SF-1487 REV. A1

iv

Operation & Troubleshooting

Go To Table Of Contents

Operation & Troubleshooting

Mode Page

Electrical System:

M7 (-011 thru -016) ...........................

M7 (-020 thru -022) ...........................

Filling the Chamber .............................. A-8

Heat Up / Sterilization ........................... A-14

Venting the Chamber ............................ A-20

A-2

A-4

Models:

Serial Numbers:

Section A

A-1

Operation & Troubleshooting

Go To Table Of Contents

Back

The illustration shows all of the electrical components of the sterilzer.

Refer to the following page for a detailed description of current flow.

Overheat

Thermostat

(Manual-Reset)

Com.

Overheat

Thermostat

(Auto-Reset)

Troubleshooting

[Electrical System]

Problem: Page

Heating element does not turn ON:

- Heater light is OFF ...............................

- Heater light is ON

.............................

Sterilizer shuts down before

timer setting expires .........................

Timer buzzer does not function ...........

A-6

A-7

A-17

A-19

Electrical System

A-2

Heating Element

Com.

Temperature

Regulator

Relay

Serial Numbers:

Heater

Light

Models:

Timer

Buzzer

Timer

MA670901i

M7 (-011 thru -016)

all

Operation & Troubleshooting

Go To Table Of Contents

Electrical System - [M7 (-011 thru -016)]

With the power cord properly connected...

Overheat Thermostats

Current

closed)

If either thermostat opens from the timer until the thermostat is reset or replaced.

NOTE

The Manual-Reset Thermostat contacts open at approximately 285°F (140°C). To reset, allow unit to cool, then press RESET button on front of unit.

The Auto-Reset Thermostat contacts open at approximately 295°F (146°C). This thermostat automatically resets when the unit cools to approx. 265°F (129°C).

Timer

Current is supplied to the timer thru the two overheat thermostats.

When the timer is turned ON...

Timer

The timer motor and the temperature regulator relay. The timer motor runs, and begins to count down the time it was set for.

(The contacts to the timer buzzer remain open).

(115 / 230 VAC)

overheat thermostats. This current supplies power to the timer.

(normally open)

continuously flows thru the two

(overheat or malfunction),

timer contacts close, and voltage is supplied to the

(normally

voltage is removed

When the timer is turned ON (continued)...

Heater Light & Heating Element

When the contacts of the temperature regulator relay are closed, current is supplied to the heater light and the heating element.

As the relay contacts open and close, the heating element cycles ON / OFF. This continues until the timer setting expires.

The heater light is illuminated whenever the heating element is ON.

When the timer setting expires...

Timer & Timer Buzzer

The contacts to the temperature regulator relay open, stopping the current flow to the heater light & heating element.

The contacts to the timer buzzer close and current flows to the timer buzzer. When voltage is applied, the buzzer emits an audible signal.

The contacts to the timer motor remain closed for one minute. After one minute the contacts to the timer motor & the timer buzzer open, stopping the current flow to these two components.

Temperature Regulator Relay

Current is supplied to the temperature regulator relay thru the timer. If the chamber temperature is lower than the temperature knob setting*, the relay contacts are closed. When these contacts are closed, current flows thru the relay to the heating element and the heater light.

The diaphragm cup of the relay expands as the temperature & pressure inside the chamber increase. When the chamber temperature reaches the temperature knob setting, the relay contacts open, and voltage is removed from the heating element & heater light.

[* The minimum temperature knob setting is approx. 220°F (104°C)]

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Electrical System

A-3

Operation & Troubleshooting

Go To Table Of Contents

Electrical System - [M7 (-020 thru -022)]

The illustration shows all of the electrical components of the sterilzer.

Refer to the following page for a detailed description of current flow.

Fuse

Overheat

Thermostat

(Manual-Reset)

Troubleshooting

[Electrical System]

Problem: Page

When Fill/Vent Switch is pressed:

- Chamber does not FILL .......................

- Chamber does not VENT .....................

Heating element does not turn ON:

- Heater light is OFF ...............................

- Heater light is ON

.............................

Sterilizer shuts down before

timer setting expires .........................

Timer buzzer does not function ...........

A-11

A-23

A-6

A-7

A-17

A-19

Com.

Heating Element

Com.

Temperature

Regulator

Relay

Heater

Light

Timer

Buzzer

Com.

Overheat

Thermostat

(Auto-Reset)

Timer

Fill / Vent

Switch

Fill / Vent

Valve

MA670900i

Electrical System

A-4

Models:

Serial Numbers:

M7 (-020 thru -022)

all

Operation & Troubleshooting

Go To Table Of Contents

Electrical System - [M7 (-020 thru -022)]

With the power cord properly connected...

Fuse

Current back of the unit. This current supplies power to the fill / vent switch and the overheat thermostats.

Fill / Vent Switch

Current is supplied to the fill / vent switch thru the fuse.

Overheat Thermostats & Timer

Current is supplied to the two overheat thermostats thru the fuse. Current continuously flows thru the thermostats to the timer.

If either thermostat opens from the timer until the thermostat is reset or replaced.

NOTE

The Manual-Reset Thermostat contacts open at approximately 285°F (140°C). To reset, allow unit to cool, then press RESET button on front of unit.

The Auto-Reset Thermostat contacts open at approximately 295°F (146°C). This thermostat automatically resets when the unit cools to approx. 265°F (129°C).

(115 / 230 VAC)

continuously flows thru the fuse located in the

(overheat or malfunction),

voltage is removed

When the timer is turned ON (continued)...

Temperature Regulator Relay

Current is supplied to the temperature regulator relay thru the timer. If the chamber temperature is lower than the temperature knob setting*, the relay contacts are closed. When these contacts are closed, current flows thru the relay to the heating element and the heater light.

[* The minimum temperature knob setting is approx. 220°F (104°C)]

The diaphragm cup of the relay expands as the temperature & pressure inside the chamber increase. When the chamber temperature reaches the temperature knob setting, the relay contacts open, and voltage is removed from the heating element & heater light.

Heater Light & Heating Element

When the contacts of the temperature regulator relay are closed, current is supplied to the heater light and the heating element. As the relay contacts open and close, the heating element cycles ON / OFF. This continues until the timer setting expires. The heater light is illuminated whenever the heating element is ON.

When the timer setting expires...

Timer & Timer Buzzer

The contacts to the temperature regulator relay open, stopping the current flow to the heater light & heating element.

When filling the chamber (pressing the fill/vent switch)...

Fill / Vent Switch

The contacts of the switch are closed, current is supplied to the fill / vent valve.

Fill / Vent Valve

When current is applied to the When the valve is open, water flows into the chamber.

When the Timer is turned ON...

Timer

The

(normally open)

timer motor and the temperature regulator relay. The timer motor runs, and begins to count down the time it was set for.

(The contacts to the timer buzzer remain open).

Models:

Serial Numbers:

(normally open)

timer contacts close, and voltage is supplied to the

switch close. When the contacts of the

(normally closed)

valve, the valve opens.

M7 (-020 thru -022)

all

The contacts to the timer buzzer close and current flows to the timer buzzer. When voltage is applied, the buzzer emits an audible signal.

The contacts to the timer motor remain closed for one minute. After one minute the contacts to the timer motor & the timer buzzer open, stopping the current flow to these two components.

When pressing the Fill / Vent Switch (to VENT the chamber)...

Fill / Vent Switch

The contacts of the switch are closed, current is supplied to the fill / vent valve.

(normally open)

switch close. When the contacts of the

Fill / Vent Valve

When current is applied to the When the valve is open, steam is released thru the condensing coil & the water is returned to the reservoir .

(normally closed)

Electrical System

valve, the valve opens.

A-5

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

4th

Loose / Damaged Wire Connections

Check all wiring connections. (Power cord, overheat thermostats, etc.)

33

3

33

Problem: Heating element does not turn ON.

M7 (-020 thru -022) only

Fuse

[Heater light is OFF]

3rd

33

3

33

Timer

Press RESET button

Allow unit to cool for 15-20 minutes before pressing RESET button.

1st

7th

33

3

33

R

33

3

33

Temperature Regulator Assy.

Overheat Thermostats

5th

6th

33

3

33

Check supply voltage

(A dedicated circuit is recommended)

33

3

33

MA670800i

2nd

33

3

33

Electrical System

A-6

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Problem: Heating element does not turn ON.

Go To Table Of Contents

[Heater light is ON]

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Models:

Serial Numbers:

Heating

1st

33

3

33

Element

M7 (-011 thru -016)

all

R

M7 (-020 thru -022)

all

MA672300i

Electrical System

A-7

Operation & Troubleshooting

Go To Table Of Contents

Filling the Chamber

The illustrations show the water flow when filling the chamber.

Refer to the following page for a detailed description of this process.

M7 (-011 thru -016)

Reservoir

Troubleshooting

[Filling the Chamber]

Problem: Page

Chamber does not fill:

- M7 (-011 thru -016) ..............................

- M7 (-020 thru -022) ..............................

A-10

A-11

Water continuously flows into chamber:

- M7 (-011 thru -016) ..............................

- M7 (-020 thru -022)

...........................

A-12

A-13

M7 (-020 thru -022)

Filling the Chamber

A-8

Fill / Vent Valve

(open)

= Water

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Filter Screen

Fill / Vent Valve

(open)

M7 (-020 thru -022)

all

Reservoir

MA671500i

Filling the Chamber

Go To Table Of Contents

Operation & Troubleshooting

M7 (-011 thru -016)

When the Fill / Vent Lever is pressed and held...

Fill Vent Valve

The

(normally closed - manual)

from the reservoir flows thru the fill / vent valve into the chamber.

When the Fill / Vent Lever is released...

Fill / Vent Valve

The valve closes, and stops the flow of water into the chamber.

R

valve opens. When the valve is open, water

M7 (-020 thru -022)

When the Fill / Vent Switch is pressed and held...

Fill / Vent Switch & Valve

Current voltage is applied, the is open, water from the reservoir flows into the chamber thru the valve and filter screen.

When the Fill / Vent Switch is released...

Fill / Vent Switch & Valve

The fill/vent switch opens, stopping the current flow to the fill/vent valve. When voltage is removed, the valve closes. When the valve closes, water stops flowing into the chamber.

(line voltage)

flows thru the fill/vent switch to the fill/vent valve. When

(normally closed)

R

fill / vent valve opens. When the valve

Fill / Vent

Lever

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Fill / Vent

Switch

MA512903i

Filling the Chamber

A-9

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

R

Problem: Chamber does not fill.

Low water in reservoir?

Add distilled water if necessary.

1st

33

3

33

Filling the Chamber

A-10

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

MA672400i

2nd

33

3

33

Problem: Chamber does not fill.

Go To Table Of Contents

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Filter Screen

Clean / replace as necessary.

2nd

Fill / Vent Switch

33

3

33

R

6th

33

3

33

Fuse

Low water in reservoir?

Add distilled water if necessary.

4th

33

3

33

1st

33

3

33

Check supply voltage

(A dedicated circuit is recommended)

3rd

33

3

33

Models:

Serial Numbers:

M7 (-020 thru -022)

all

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

Filling the Chamber

5th

33

3

33

A-11

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

R

Problem: Water continuously flows into chamber.

Filling the Chamber

A-12

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

MA672400i

1st

33

3

33

Problem: Water continuously flows into chamber.

Go To Table Of Contents

R

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Models:

Serial Numbers:

Fill / Vent Switch

M7 (-020 thru -022)

all

2nd

33

3

33

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

Filling the Chamber

1st

33

3

33

A-13

Operation & Troubleshooting

Go To Table Of Contents

Heat Up / Sterilization

The illustrations show the water / steam flow during heat up & sterilization.

Refer to the following page for a detailed description of this process.

Heat-Up

Bellows

(open)

Temperature

Regulator Relay

(closed)

Troubleshooting

[Heat-Up / Sterilization]

Problem: Page

Heating element does not turn ON:

- Heater light is OFF ...............................

- Heater light is ON

.............................

A-6 A-7

Heating element turns ON, but does not

reach required temperature ..............

A-16

Sterilizer shuts down before

timer setting expires .........................

A-17

Biological test strips indicate items

are not sterile ...................................

Timer buzzer does not function ...........

A-18

A-19

Sterilization

Pressure Relief Valve

(closed)

= Water

= Heated Water

= Steam

Heat-Up / Sterilization

A-14

Fill / Vent Valve

(closed)

Note: Electronic valve is shown.

Manual valve is also closed.

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Temperature

Regulator Relay

(closed / open)

Fill / Vent Valve

Note: Electronic valve is shown.

Manual valve is also closed.

M7 (-020 thru -022)

all

Bellows

(closed)

MA672000i

(closed)

Heat-Up / Sterilization

Go To Table Of Contents

Operation & Troubleshooting

When the timer is turned ON...

Timer

The

(normally open)

timer motor and the temperature regulator relay. The timer motor runs, and begins to count down the time it was set for.

timer contacts close, and voltage is supplied to the

(The contacts to the timer buzzer remain open).

Temper

Current is supplied to the temperature regulator relay thru the timer. If the chamber temperature is lower than the temperature knob setting*, the relay contacts are closed. When these contacts are closed, current flows thru the relay to the heating element and the heater light.

ature Regulator Relay

[* The minimum temperature knob setting is approx. 220°F (104°C)]

The diaphragm cup of the relay expands as the temperature & pressure inside the chamber increase. When the chamber temperature reaches the temperature knob setting, the relay contacts open, and voltage is removed from the heating element & heater light.

Heater Light & Heating Element

When the contacts of the temperature regulator relay are closed, current is supplied to the heater light and the heating element.

As the relay contacts open and close, the heating element cycles ON / OFF. This continues until the timer setting expires.

When the timer setting expires...

Timer &

The contacts to the temperature regulator relay open, stopping the current flow to the heater light & heating element.

The contacts to the timer buzzer close and current flows to the timer buzzer. When voltage is applied, the buzzer emits an audible signal.

The contacts to the timer motor remain closed for one minute. After one minute the contacts to the timer motor & the timer buzzer open, stopping the current flow to these two components.

Timer Buzzer

R

The heater light is illuminated whenever the heating element is ON.

Bello

ws & Pressure Relief Valve

Heat-Up: As the water in the chamber begins to boil, air is forced out of the chamber. This air passes thru the bellows into the reservoir.

Sterilization: When pure steam begins to flow thru the bellows, the bellows closes allowing pressure to build in the chamber. If the pressure in the chamber exceeds 34 psi (234 kPa), the pressure relief valve opens to prevent unsafe conditions.

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Temperature Knob

Timer Knob

MA672100i

Heat-Up / Sterilization

A-15

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Refer to Section B for checkpoints.

1st

33

3Check for pressure leaks.

33

Problem: Heating element turns ON, but does

not reach required temperature. [Heater light is ON]

Heating Element

Heat-Up / Sterilization

A-16

3rd

33

3

33

Models:

Serial Numbers:

R

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

MA672700i

Temperature Regulator Assy.

2nd

33

3

33

Problem: Sterilizer shuts down before timer setting expires.

Go To Table Of Contents

Check for pressure leaks.

Refer to Section B for checkpoints.

1st

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

33

3

33

Timer

Press RESET button

Allow unit to cool for 15-20 minutes before pressing RESET button.

2nd

33

3

33

5th

R

33

3

33

Temperature Regulator Assy.

4th

33

3

33

Overheat Thermostats

MA672800i

3rd

33

3

33

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Heat-Up / Sterilization

A-17

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Problem: Biological test strips indicate items are not sterile.

Type / condition of indicator strips

This unit requires test strips rated for:

Gravity Displacement Steam Sterilizers

Test strips must be stored in a cool, dry location. Failure to do so will result in faulty readings.

(Follow all instructions provided with test strips)

1st

33

3

33

Is the sterlizer overloaded?

Large loads or heavy linen packs may prevent strips from changing.

Are the correct trays being used?

Some trays may prevent proper air flow. Be sure trays are designed for this sterilizer.

3rd

2nd

33

3

33

3

33

4th

5th

33

3

33

3

33

Check for pressure leaks.

Refer to Section B for checkpoints.

R

Temperature Regulator Assy.

MA672900i

Heat-Up / Sterilization

A-18

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Problem: Timer buzzer does not function.

Go To Table Of Contents

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Timer Buzzer

R

1st

33

3

33

MA672900i

Models:

Serial Numbers:

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Heat-Up / Sterilization

A-19

Operation & Troubleshooting

Go To Table Of Contents

Venting the Chamber

The illustrations show the steam / water flow when venting the chamber.

Refer to the following page for a detailed description of this process.

M7 (-011 thru -016)

Condensing Coil

Troubleshooting

[Venting the Chamber]

Problem: Page

Chamber will not vent:

- M7 (-011 thru -016) ..............................

- M7 (-020 thru -022) ..............................

M7 (-020 thru -022)

A-22

A-23

Venting the Chamber

A-20

= Water

= Steam

Fill / Vent Valve

(open)

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Fill / Vent Valve

(open)

M7 (-020 thru -022)

all

Filter Screen

Condensing Coil

MA672200i

Venting the Chamber

Go To Table Of Contents

Operation & Troubleshooting

Attention

The door handle

must be moved to the VENT position

before pressing the Fill / Vent Lever or Switch.

M7 (-011 thru -016)

When the Fill / Vent Lever is pressed and held...

Fill / Vent Valve

The

(normally closed - manual)

and steam back into the reservoir thru the valve and the condensing coil. When all of the pressure has been vented, the door will "pop".

Note: Release the lever when the door "pops".

If the lever is held too long, the chamber will begin to fill.

When the Fill / Vent Lever is released...

Fill / Vent Valve

The valve closes.

valve opens. Pressure forces water

M7 (-020 thru -022)

When the Fill / Vent Switch is pressed and held...

Fill / Vent Switch & Valve

Current voltage is applied, the water and steam back into the reservoir thru the valve and the condensing coil. When all of the pressure has been vented, the door will "pop".

Note: Release the lever when the door "pops".

When the Fill / Vent Switch is released...

Fill / Vent Switch & Valve

The fill/vent switch opens, stopping the current flow to the fill/vent valve. When voltage is removed, the valve closes.

(line voltage)

flows thru the fill/vent switch to the fill/vent valve. When

(normally closed)

fill / vent valve opens. Pressure forces

If the lever is held too long, the chamber will begin to fill.

Fill / Vent

Lever

Models:

Serial Numbers:

R

M7 (-011 thru -016)

all

M7 (-020 thru -022)

all

Fill / Vent

Switch

R

MA512903i

Venting the Chamber

A-21

Operation & Troubleshooting

Go To Table Of Contents

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

R

Problem: Chamber will not vent.

Venting the Chamber

A-22

Models:

Serial Numbers:

M7 (-011 thru -016)

all

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

MA672400i

1st

33

3

33

Problem: Chamber will not vent.

Go To Table Of Contents

Operation & Troubleshooting

Refer To: Page

Operation & Troubleshooting ................ A-1

Component Testing / Repair ................. B-1

Access Procedures .............................. C-1

Wiring Diagrams ................................... D-1

Exploded Views / Part Numbers ........... E-1

Filter Screen

Clean / replace as necessary.

Models:

Serial Numbers:

1st

33

3

33

Fill / Vent Switch

M7 (-020 thru -022)

all

R

3rd

33

3

33

Fill / Vent Valve & Tubing

Clean / adjust / replace as necessary.

Venting the Chamber

2nd

33

3

33

A-23

Go To Table Of Contents

Midmark M7-2 Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual