Viessmann Vitocrossal 200 C12 Installation and Start-up Guide

Important Information

This guide provides a quick overview for installing the Vitocrossal 200 C12 boiler. It is not a substitute for the technical support literature supplied with the boiler and accessories, which contains essential safety and code requirements. Failure to follow this literature may result in property damage, personal injury, or loss of life. Viessmann Manufacturing assumes no responsibility for damages caused by inappropriate use or failure to read the provided technical literature, which may void the warranty.

Codes: Installation must comply with local codes, or CAN/CSA-B149.1 or .2 for Canada, and ANSI Z223.1 (National Fuel Gas Code) for the U.S. Electrical wiring must comply with CSA C22.1 Part 1 in Canada and ANSI/NFPA 70 (National Electrical Code) in the U.S. Compliance with ANSI/ASME CSD-1 and CSA B214-01 is also required where applicable.

Gas Type: The boiler is factory configured for Natural Gas. A conversion kit is supplied for Propane Gas conversion.

1. Unpacking the Boiler

The boiler is delivered on a wooden pallet. Remove packaging and unscrew transport brackets. The boiler can be lifted by crane only while packed on the skid.

2. Positioning the Boiler

Note: Levelling feet must be used once the boiler is in its final position.

CI2 1500/2000

1. Using an open-end wrench, adjust the levelling feet in the base frame so the wheels are off the ground.
2. It is recommended to place a flat steel plate under each levelling bolt for better weight distribution and adjustment.

3. Accessing the Boiler

Removing the front panels:

1. Turn off the power switch and disconnect the power supply. Close the gas shut-off valve.
2. Flip open the panel handle at the top of the upper front panel.
3. Pull up the upper front panel using the handle.
4. While holding the handle, use a screwdriver to release the panel retaining clip.
5. Pull up to finish removing the panel. CAUTION: Failure to keep a firm grip on the panel handle may cause the upper front panel to fall, causing injury.
6. Using a screwdriver, press down on the lower front panel release.
7. Pull the top of the lower front panel away from the boiler and lift up to remove.

To access the BCU and control unit:

1. Turn off the power switch and disconnect the power supply. Close the gas shut-off valve.
2. Remove junction box retaining screws and set aside. Swing the junction box access door open.
3. Push back top panels to access the front panel release (top panel removal is not required).
4. Using a screwdriver, push down on the front panel releases.
5. Pull forward at the top of the front panel and lift up to remove.

4. Boiler Connections

Legend:

• ① Boiler return: 2 in. NPT for C12 399/500; 2 1/2 in. ANSI flange for C12 750/1000; 4 in. ANSI flange for C12 1500/2000. (*1 Counter flanges, gaskets and hardware field supplied)
• ② Boiler supply: 2 in. NPT for C12 399/500; 2 1/2 in. ANSI flange for C12 750/1000; 4 in. ANSI flange for C12 1500/2000. (*1 Counter flanges, gaskets and hardware field supplied)
• ③ Safety header: Includes pressure relief valve, low water cutoff, automatic air vent, and temperature/pressure gauge. Components include hex bushing, air vent with shut-off base, street elbow, reducing elbow, nipple, pressure relief valve (80 psi *2), low water cutoff, temperature/pressure gauge, and reducer. (*2 Alternate pressure relief valves available; contact local Viessmann sales representative).
• ④ Drains: Reducer, sediment faucet.
• Gas line fittings: Gas shut-off valve (1 1/2 in. for models 399-1000, 2 in. for models 1500-2000).

5. Installing the Condensate Trap

CI2 399 to 1000

Legend: A - Condensate drain connection, Condensate trap, Drain line.

CI2 1500 and 2000

6. Connecting the Neutralization System

CI2, 399 to 1000

Legend: A - Vitocrossal 200 C12, Condensate trap, Condensate trap hose (included) to neutralizing system (accessories).

CI2, 1500 and 2000

7. Making the Fuel Gas Connections

Legend: A - Manual gas shutoff valve (supplied), B - Nipple (field supplied), E - Ground joint union (recommended, field supplied), T - Tee (field supplied), C - Cap (field supplied), On site gas line.

8. Accessing the DIN Rail

CI2 399 to 1000

Rear of the boiler

Legend: Drain hose, Drain (on-site).

1. Remove two screws for junction box access door.
2. Rotate junction box access door to remove.
3. Select an available knock-out on the rear jacketing of the boiler.
4. Remove the knock-out and apply a strain relief to the opening.
5. Route the cable through the strain relief to the DIN rail or Control boards (WP or MZIO), as required.

9. Boiler Control Locations

Location of the control unit components for C12 399 to 1000

Front of the boiler

Legend: A - Burner control unit 1 (BCU), B - Burner control unit 2 (BCU).

CI2 1500/2000

Front of the boiler

Legend: Control unit with WP and MZIO, LAN socket, DIN rail.

Rear of the boiler

Legend: Control unit with WP and MZIO, LAN socket, DIN rail.

10. Connection on MZIO/WP Boards

Overview of connections to the wiring panel and MZIO. Note: For further information on the connections, see the following chapters.

Wiring panel

MZIO

P1 Output 120V for: Zone 1 pump, DHW pump.

P2 Output 120V for: Zone 2 pump, Zone 3 pump, Heating circuit pump for heating circuit.

S Potential-free changeover contact: Normally closed (NC), Normally open (NO), COM.

ZI1 Zone 1 or safety input 1

ZI2 Zone 2 or safety input 2

ZI3 Zone 3 or safety input 3

CAI Combustion air interlock

DIS Digital input (burner lockout)

91 CAN BUS connection

74 PlusBus

TS1 Low loss header sensor

F1 Fuse 6.3 A (slow), 120V

F2 Fuse 1 A (slow), 120V

0-10V OUT Output 0-10V (burner modulation feedback)

0-10V IN Input 0-10V

1 Outside temperature sensor, terminals 1 and 2

5 Tank temperature sensor or temperature switch such as an Aquastat, terminals 3 and 4

96 External call for heat

12 Connecting Accessories

Accessories with direct power supply. When connecting accessories, observe the separate installation instructions provided with them.

11. Typical Single Pipe and Coaxial Pipe Venting Layouts

Legend: A - Lead boiler, B - Mixing valve extension kit, EM-EA1 extension and/or EM-P1 extension, PlusBus.

Two pipe vertical exhaust/vertical intake

Vertical intake and exhaust

Two pipe vertical exhaust/horizontal intake

Two pipe - horizontal exhaust/horizontal intake

Boiler flue collar (internal diameter): 4 in. (104.2 mm) for C12 399/500; 6 in. (155 mm) for C12 750/1000/1500; 8 in. (205.2 mm) for C12 2000.

Combustion air intake diameter: 4 in. (104.2 mm) for C12 399/500; 6 in. (155 mm) for C12 750/1000/1500; 8 in. (205.2 mm) for C12 2000.

Max. total equivalent length (a+b): 198 ft. (60 m) for all models.

13. Electrical Connections DIN Rail

DIN rail C12 399 to 1000

DIN rail CI2 1500/2000

Legend: A - Boiler DIN rail, Low water cutoff (typical).

Switch A settings:

• If the boiler is not integrated into a CAN bus system: Switch A must not be set to "ON".
• If the boiler is integrated in a CAN bus system and is located at the beginning or end of this system (not in the middle): Set switch A to "ON" (switched on).
• If the boiler is integrated in a CAN bus system and is not located at the beginning or end of this system: Do not set switch A to "ON" (switched off).

Legend: Boiler, CAN bus cable, Other subscribers.

Legend: C - Flue gas damper for common venting feedback, D - Flue gas damper for common venting power supply, E - Boiler isolation valve (power open spring return), F - Boiler pump power supply, G - Boiler pump modulation signal (0-10VDC), F1 - Fuse 6.3 (slow) 120VAC.

14. Connection of Low Water Cut-off Device

Note: The boiler is supplied with a LWCO wiring harness.

1. Make connection for (LWCO) switching contact at terminals 16 and 17.
2. Power supply for low water cut-off device made at terminal 4 and terminal 6.

CAUTION: The diagram shown is a simplified conceptual drawing. Refer to the device's manual for interconnection details.

Legend: A - Low water cut-off power supply, B - Low water cut-off feedback.

15. Connecting the Boiler Power Supply

IMPORTANT

Electrical installations must comply with the latest edition of:

• In the U.S.A., the National Electrical Code (NEC), ANSI/NFPA 70 and any other state, local codes and/or regulations.
• In Canada, the Canadian Electrical Code (CEC), CSA C22.1 Part 1 and any other province, territory, local codes and/or regulations.

CI2 399 to 1000

POWER SUPPLY: 120VAC-1Ph-60Hz, 10 Amps

CI2 1500 and 2000

POWER SUPPLY: 120VAC-1Ph-60Hz, 20 Amps (Full Load)

WARNING: The control must be grounded. Ensure that 'L', 'N' and 'G' are not interchanged.

WARNING: Incorrectly executed electrical installations can lead to injuries from electrical current and result in appliance damage.

16. Making the Vent Connection

Legend: A - Flue vent collar coupling (supplied with boiler), Approved venting (field supplied).

Flue

Exhaust length

Intake length

17. Starting the Boiler Using the Commissioning Assistant

The commissioning assistant guides you through the initial setup. Options include setting language, units of measurement, date/time, operating mode (weather-compensated, constant), gas type (Natural Gas/LPG), and flue system type (single or multiple connections). Flue length adjustment is also configured here.

Commissioning Assistant Sequence:

• Language: Factory setting is English. Can be changed via programming unit or software tool.
• Units of measurement: Set as needed.
• Date and time: Set the current time.
• Operating mode: Weather-compensated (requires outside temperature sensor), Constant operation.
• Gas type: Select Natural Gas or LPG.
• Flue system type: Single connection (factory setting) or Multiple connections (common venting).
• Flue length adjustment: Specify effective flue and ventilation air length.

System Scheme: Configure settings for heating circuits (with/without mixing valve), DHW heating (system without DHW, with DHW tank, with DHW recirculation pump), and low loss header/buffer tank configurations.

Floating contact (plug 96): Can be set for no function, external demand (DHW circulation pump, boiler demand), external blocking, or heat demand.

EM-EA1 (DIO): Function selection for connected extension modules.

Remote control units: Assign remote controls to heating circuits.

Boiler pump: Select On/off control or 0-10V modulation control.

Maintenance: Set intervals for next maintenance (burner hours run or months).

Note: Apps for commissioning and service are available for iOS and Android devices.

18. Setting the Room Temperature

1. Tap the header bar and select the desired heating circuit.
2. Tap '-'.
3. Tap '+' for desired temperature adjustment (reduced, standard, or comfort).
4. Tap '✔' to confirm.

19. Adjusting the Heating Curve

The heating curve influences the supply temperature based on outside temperature. Adjust "Shift" and "Slope" for optimal room heating.

Factory settings: "Slope": 1.4, "Shift": 0.

Typical Settings:

• Radiant: 1.4 slope & 0 curve set point
• Baseboard: 2.4 slope & 0 curve set point
• Fan Coil: 0.8 slope & 15 curve set point

Procedure:

1. Tap the following buttons: 1. =, 2. "Heating", 3. Select "heating zone or heating circuit".
2. Select a heating zone or heating circuit (e.g., "Heating circuit 1").
3. Select "Heating curve".
4. Use '+' for the required value for "Slope" and "Shift". The graph shows the change.
5. Tap '✔' to confirm.

Note: Heating curve adjustment is only possible in weather-compensated operation.

20. Setting DHW Temperature

Note: Not valid for systems with a DHW tank with temperature switch (e.g., Aquastat).

Factory setting: 122°F (50°C).

Procedure:

1. If applicable, tap for the "DHW" default display.
2. Tap '+' for the required value.
3. Tap '✔' to confirm.

Note: For hygiene reasons, do not set DHW temperature lower than 122°F (50°C).