Buderus MCM10 Installation Instructions

1.1 Explanation of Symbols

Warning symbols are framed and identified by a warning triangle on a grey background. Electrical hazards are identified by a lightning symbol within a warning triangle.

Signal words indicate hazard seriousness:

• NOTICE: Possible damage to property or equipment, no risk of injury.
• CAUTION: Possible injury.
• WARNING: Possible severe injury.
• DANGER: Possible risk to life.

Important information notes are bordered by horizontal lines.

Additional symbols:

• • (Bullet point): A step in an action sequence.
• • (Bullet point): A reference to a related part in the document or other documents.
• • (Bullet point): A list entry.
• • (Bullet point): A list entry (second level).

1.2 Safety Precautions

• Ensure proper function by following these instructions.
• Install and start up the heating appliance and accessories according to associated instructions.
• Use this accessory exclusively with listed controllers and heating appliances. Follow the connection diagram.
• This accessory has inputs and outputs with different voltages. Never connect the low voltage side to the 120 V power supply or vice-versa.
• In case of wall installation, never install this accessory in wet areas.
• Work on electrical components only if you have the required training and qualification.
• Before working on the system, disconnect the heating system from electrical power by shutting off the emergency shut-off switch or circuit breaker.
• Secure against unintentional reconnection. Shutting off controls is not sufficient.
• Observe all applicable electrical codes and regulations.

2.1 Declaration of Conformity

The design and operation conform to U.S. and Canadian Directives, demonstrated by the CSA designation. Declaration of conformity can be claimed; see address at the back of this manual.

2.2 Information Regarding the Documentation

Hand all enclosed documents over to the user. Technical modifications are reserved.

2.3 Proper Use

The MCM10 modules control cascade systems, where multiple heating appliances are connected in parallel for higher output. They are suitable for controlling heating appliances with Logamatic EMS BUS. For floor-standing heaters, they are suitable for gas heaters with modulating burners without operating conditions.

2.4 Scope of Delivery

The MCM10 module package includes:

• MCM10 unit
• Duct connection box
• Sensor well
• Supply temperature sensor FV
• Package contents: 3 screws and 3 wall-plugs, 4 strain relief clips and 8 screws
• Installation and operating instructions

Check that the delivery is complete.

2.5 Accessories

Typical accessories include:

• Outdoor temperature sensor FA (for terminal F, system variant 1).
• RC35: Outdoor reset heating system control with plaintext display.
• WM10: Low loss header module for EMS.
• MM10: Mixer module for EMS.
• AM10: Outdoor reset controller with thermostat connection.

Contact the manufacturer for a complete overview of available accessories.

2.6 Technical Specifications

2.6.1 General

2.6.2 Dimensions

Diagram showing dimensions: 9-1/4" (235mm) width, 6-1/2" (165mm) height, 5-9/16" (142mm) depth. Other dimensions include 2-1/2" (62mm) and 2-1/4" (58mm).

2.6.3 Power Connection Parameters

2.6.4 Measurement Values Supply Temperature Sensor

2.6.5 Measurement Values Outdoor Temperature Sensor

2.7 System Integration of the MCM10

2.7.1 Principles of Cascade Control

When a heat demand is detected, the MCM10 module starts heating appliances sequentially. If heat generation is excessive, appliances are reduced in power or shut down. The MCM10 module ensures even distribution of burner hours for all appliances, increasing service life. If power is interrupted, hour meters reset.

If an appliance is unavailable, another is automatically started to meet demand.

2.7.2 Heating Controls for MCM10 Cascade Systems

MCM10 modules stage heating appliances based on calculated heat demand, requiring heating system controls (terminals H, I, or J). Four system versions are possible depending on the control. Only one control system/building management system can be connected.

One MCM10 module can control up to four appliances. Up to four MCM10 modules can form a cascade of up to 16 appliances, with one acting as master.

Different system versions require specific accessories (sensors, pumps, controls).

The MCM10 module controls the primary boiler loop. Other components (heating zones, hot water tanks) can be regulated by weather-dependent controllers with BUS interfaces and additional modules (WM10, MM10). Contact the manufacturer for details.

2.7.3 Water Heating with MCM10 Cascade Systems

Hot water tanks can be connected directly. The heating appliance controls water heating. During DHW demand, this appliance is not called by MCM10; another appliance may start. If water heating is timed via a BUS control, the storage tank appliance must connect to the MCM10 master via terminals 17 and 18.

If hot water is prepared via the 3-way valve and heating zones are still supplied, hot water priority must be switched off on the RC35 for all heating zones.

2.7.4 Internal Frost Protection Function

The MCM10 has an internal frost protection function: if supply temperature drops below 45 °F (7 °C), a heating appliance starts until 60 °F (15 °C) is reached. Connected heating pumps also run.

Connect the supply temperature sensor to the MCM10 master for this function. A BUS thermostat with an outdoor temperature sensor provides comprehensive frost protection.

2.7.5 Control of One Heating Pump

For systems with one heating zone, the pump can connect directly to the MCM10 master. The pump runs as long as a heating appliance pump is running, or briefly after 24 hours idle (anti-seizing). The anti-seizing function runs the pump daily, even without heat demand. Leave the system on year-round to prevent seizing.

2.7.6 External Switching Contact

The MCM10 has an external switching contact (Fig. 12, pos. G). This can be used, for example, to connect a temperature switch for floor heating protection. If the contact opens, all heating appliances shut off. When it closes, they are ready for operation.

2.7.7 System Versions Overview

Buderus emphasizes economical and clean-burning appliances with modulating burners. For optimal use, heating system controls with 2-wire BUS control should be used.

System version 1: Modulating weather-compensated heating controller (RC35): Enables communication for heating zones via common BUS, optimizing heat output to demand for comfort and energy savings.

System version 2: Modulating weather-compensated heating controller (AM10): Supply target temperature depends on outdoor temperature. WM10 and MM10 modules cannot be used.

System version 3: Modulating 0 - 10 V controller, regulated acc. to output: With a building management system (0-10V interface), total cascade output can be set as reference. Setting via jumper.

2.7.8 Connection of Additional Modules in Case of Heating System Controls with 2-Wire BUS Control

Additional modules (WM10, MM10) connect to the heating controller's BUS (parallel to terminal J on MCM10).

Diagrams show correlations between input voltage and heat output/supply temperature for system versions 4 and 5.

3.1 Installation

DANGER: Risk of electric shock!

Before connecting power, interrupt power to heating appliances and all other BUS subscribers.

3.1.1 Wall Mounting

Choose mounting location based on MCM10 dimensions. Consider cable routing (ducts, junction box). Remove the cover by undoing bottom screws and lifting upwards.

For the upper attachment screw, drill a 1/4" (6 mm) hole, insert anchor, and screw until 1/16" (1.5 mm) protrudes. Then, create two holes in the back panel for lower screws. Attach module to the upper screw. Mark wall holes, remove module, drill 1/4" (6 mm) holes, and insert anchors.

Hook the MCM10 module onto the upper screw and secure with the two lower screws.

When using ducts:

• Remove plastic grommets from lower slits.
• Push duct connection into place.
• Break out required cable entries carefully.
• Mount duct per manufacturer instructions.

3.2 Making the Electrical Connections

Observe electrical codes. Use at least AWG14 for the main power cord. Route cables through grommets and use strain relief to protect against water ingress. Use single-core cable or multi-strand cables with ferrules. Terminals are color-coded and keyed.

3.2.1 Connection of the Low Voltage Part with BUS Connections

CAUTION: Malfunction!

• Wire according to the wiring diagram.
• Never connect BUS to each other.

Minimum permissible cable cross-section for 2-wire BUS connections:

Route low-voltage cables separately from 120V cables (min. 4 inches / 100 mm separation) to avoid inductive interference. Use shielded cables if necessary.

For extending sensor leads:

To safeguard splash-proof rating (IP), ensure cable sheath protrudes at least 0.8" (20 mm) into the cable grommet or duct box.

CAUTION: Risk of pole reversal!

Ensure correct polarity for 0-10 V interface connection (9 = negative, 10 = positive).

3.2.2 120 V AC Connection

CAUTION: The MCM10 module input is not fuse-protected.

• Protect the MCM10 module power supply (master) with a fuse of max. 10 Amp.
• Use electric cable of similar quality.
• Never connect additional controllers to outputs C (pump) and D (fault signal).

CAUTION: Output C (pump) has a max load capacity of 250 W. Connect higher current pumps via relays.

3.2.3 Connection of a Remote Fault Indication with Optical and Acoustic Signal

A fault indicator can connect to the zero volt fault contact (Fig. 12, terminal D). Fault status is also shown via an LED on the MCM10.

This is a dry contact carrying max. 2 A at 120 V AC. Remote fault indication is enabled when power to the MCM10 master is interrupted.

3.2.4 Electrical Connection of the Outdoor Temperature Sensor

For systems with 2-wire BUS control, always connect the outdoor temperature sensor to the MCM10 master (Fig. 12, page 19), not to the heating appliance.

3.2.5 Electrical Connection of the Supply Temperature Sensor

For system version 1, connect to WM10. For versions 2, 3, 4, and 5, connect to MCM10, terminal E (Fig. 12, [18], page 19).

3.2.6 Electrical Connection of the External Switching Contact

If an external switching contact is connected, remove the bridge on the plug first.

3.2.7 Disposal

Dispose of packaging responsibly. Dispose of old components responsibly.

3.3 Installing Other Accessories

Install accessories according to regulations and supplied instructions. BUS subscribers (RC35, WM10, MM10) must connect to terminal J (Fig. 12, page 38).

4.1 Configuration

Configuration adapts the MCM10 master's control characteristics to the specific installation. It occurs automatically during first start-up or after a reset. Configuration takes at least 5 minutes. LEDs flash during this process and stop when complete. Saved configurations persist through power loss.

If an appliance is temporarily shut down during operation, its LED flashes. After restart, it's recognized and the LED stops flashing. Mismatched configurations complicate troubleshooting. Reset configuration after any significant change.

4.2 Commissioning

Cascade configuration occurs during first start-up or after reset. Monitor LEDs for cable breaks or faults. Ensure all component connections are correct. Provide power (120 V AC) to all components except MCM10 modules. Start all heating appliances. Provide power to the first MCM10 module; configuration will begin (min. 5 minutes). Make necessary adjustments on BUS subscribers per their instructions.

4.3 Configuration Reset

Resetting the MCM10 master deletes the entire configuration. Interrupt power to all MCM10 modules, open the master cover, remove the jumper. Ensure connections are correct. Restore power to all components except MCM10 modules. Start heating appliances. Restore power to the first MCM10 module; configuration begins (min. 5 minutes).

CAUTION: Malfunction!

When using system version 2 or 3, ensure the jumper is reinstalled correctly. Reinstall the jumper. Configuration starts (min. 5 minutes). Close the MCM10 module cover.

4.4 Shutting Down

WARNING: System damage due to frost!

Ensure frost protection is activated if the heating system is out of service for extended periods.

To take the system out of use: Interrupt power to all MCM10 modules and heating appliances.

5.1 Operating and Fault Indications via the Heating Appliance Displays

Check heating appliance displays for operating and fault indications; refer to appliance documentation for details.

5.2 Fault Message via the Remote Fault Indication

A fault indicator can connect to the zero volt fault contact (paragraph 3.2.3). The remote fault indication status is also shown via an MCM10 LED.

5.3 Operating and Fault Indications via LED

Three system states are identified: Configuration, Normal Operation, and Fault. MCM10 LEDs indicate the operating and fault status of individual components for troubleshooting.

Fig. 10 Operating and fault indications via LED

• 1: Line voltage (green)
• 2: Heating pump (secondary zone) (green)
• 3: Switching contact for remote fault indication 120 VAC (red)
• 4: Communication between MCM10s (green)
• 5: Heating appliance 1 (green)
• 6: Heating appliance 2 (green)
• 7: Heating appliance 3 (green)
• 8: Heating appliance 4 (green)

5.4 Operating and Fault Indications via the RC35

Indications for all heating appliances and the MCM10 module can be checked on the RC35 controller. The MCM10 display indications are explained in Table 10. Other display indications are in the controller or boiler documentation.

Packaging

Buderus participates in country-specific recycling systems for optimal recycling. All packaging materials are environmentally friendly and recyclable.

Old Appliances

Old appliances contain recyclable resources. Components can be easily separated, and plastics are marked, allowing for proper sorting for recycling or disposal.