Installation and Service Instructions

Safety, Installation and Warranty Requirements

Please ensure that these instructions are read and understood before commencing installation. Failure to comply with the instructions listed below and details printed in this manual can cause product/property damage, severe personal injury, and/or loss of life. Ensure all requirements below are understood and fulfilled (including detailed information found in manual subsections).

Product documentation

Read all applicable documentation before commencing installation. Store documentation near boiler in a readily accessible location for reference in the future by service personnel.

For a listing of applicable literature, please see section entitled "Important Regulatory and Safety Requirements".

Warranty

Information contained in this and related product documentation must be read and followed. Failure to do so renders the warranty null and void.

Licensed professional heating contractor

The installation, adjustment, service and maintenance of this equipment must be performed by a licensed professional heating contractor.

Please see section entitled Safety and "Important Regulatory and Installation Requirements".

Advice to owner

Once the installation work is complete, the heating contractor must familiarize the system operator/ultimate owner with all equipment, as well as safety precautions/requirements, shutdown procedure, and the need for professional service annually before the heating season begins.

Important Precautions

Important Regulatory and Installation Requirements

Approvals

Viessmann boilers, burners and controls are approved for sale in North America by CSA International.

Codes

The installation of this unit shall be in accordance with local codes. In the absence of local codes, use:

• CSA C22.1 Part 1 and/or local codes in Canada
• National Electrical Code ANSI/NFPA 70 in the U.S.

Always use latest editions of codes. The heating contractor must comply with the Standard for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME CSD-1 where required by the authority having jurisdiction.

Working on the equipment

The installation, adjustment, service, and maintenance of this product must be done by a licensed professional heating contractor who is qualified and experienced in the installation, service, and maintenance of hot water boilers. There are no user serviceable parts on the boiler, burner, or control.

Power supply

Install power supply in accordance with the regulations of the authorities having jurisdiction or, in absence of such requirements, in accordance with National Codes. Viessmann recommends the installation of a disconnect switch to the 120V power supply outside of the boiler room.

Ensure main power supply to equipment, the heating system, and all external controls have been deactivated. Close main oil or gas supply valve. Take precautions in both instances to avoid accidental activation of power during service work.

[WARNING] Turn off electric power supply before servicing. Contact with live electric components can cause shock or loss of life.

Please carefully read this manual prior to attempting installation. Any warranty is null and void if these instructions are not followed.

For information regarding other Viessmann System Technology componentry, please reference documentation of the respective product.

Viessmann offers frequent installation and service seminars to familiarize partners with its products. Please inquire.

The completeness and functionality of field supplied electrical controls and components must be verified by the heating contractor. These include low water cut-offs, flow switches (if used), staging controls, pumps, motorized valves, air vents, thermostats, etc.

General Information

About these Installation Instructions

Take note of all symbols and notations intended to draw attention to potential hazards or important product information.

[WARNING] Warnings draw your attention to the presence of potential hazards or important product information.

Indicates an imminently hazardous situation which, if not avoided, could result in death, serious injury or substantial product/property damage.

[CAUTION] Cautions draw your attention to the presence of potential hazards or important product information.

Indicates an imminently hazardous situation which, if not avoided, may result in minor injury or product / property damage.

[IMPORTANT] Helpful hints for installation, operation or maintenance which pertain to the product.

This symbol indicates to note additional information.

This symbol indicates that other instructions must be referenced.

Intended Use

The appliance is only intended to be installed and operated in sealed unvented heating systems, with due attention paid to the associated installation, service and operating instructions as well as the details in the datasheet. It is only designed for the heating up of heating water. Commercial or industrial usage for a purpose other than the heating up of heating water shall be deemed inappropriate.

Intended use presupposes that a fixed installation in conjunction with permissible components designed for this purpose has been carried out. Every other use will be deemed to be inappropriate. Any resulting losses are excluded from the manufacturer's liability. Any usage beyond this must be approved by the manufacturer for the individual case. Intended use also includes the adherence to maintenance and inspection intervals.

Product Information

Spare parts lists

Information about spare parts can be found on the Viessmann spare parts app.

Available on the App Store. Get it on Google Play.

The following circulation pumps can be connected:

• Heating circuit pump for heating circuit without mixing valve
• DHW recirculation pump

Installation

Mounting the Extension

A diagram shows the EM-P1 Extension enclosure with screws being loosened and the cover being removed. A second diagram illustrates mounting the enclosure to a wall using hardware and then reattaching the cover.

1. Loosen the retaining screws from the extension kit enclosure (do not remove).
2. Remove cover and set aside.
3. Mount the extension module enclosure to the wall using the supplied hardware.
4. Install the cover.

Connections

Overview of Electrical Connections

A diagram shows terminal blocks and plugs for the EM-P1 Extension. Connections include: 120VAC power input (L, N, G), heating circuit pump (P1), DHW recirculation pump (P3), power supply for accessories (40A), and PlusBus (74). Low Voltage (LV) connections are listed as PWM1, TS1, TS2, TS3, all marked as 'No function'.

[CAUTION] The electronic modules are static sensitive. To avoid damage caused by static discharge, follow Electro-Static Discharge safety procedures.

Note: Apply strain relief to on-site cables. Secure individual wires directly to each plug using cable ties. Seal any unnecessary apertures with cable grommets (not cut open).

Connecting the DHW Recirculation Pump

A diagram illustrates connecting the DHW recirculation pump (A) to the EM-P1 Extension via plug 46 into slot P3 (B).

1. If there is already a plug connected to the DHW recirculation pump: Remove it and connect plug 46.
2. Insert the plug into slot P3.

Specification

Connecting the Heating Circuit Pump

Heating circuit pump 120V~

A wiring diagram shows a 120V heating circuit pump (A) connected via a contactor/relay (B) to a 120V power supply (C) with disconnect and protection, which then connects to the extension kit (D).

Specification of the heating circuit pump 120V~

Rated current: > 1A

Specification of the contactor:

Heating circuit pump 240V~

A wiring diagram for a 240V heating circuit pump shows the pump (A) connected via a contactor/relay (B) to a 240V/1/60 VAC power supply (C) with disconnect and protection, connecting to the extension kit (D). A note advises integrating a temperature limiter for underfloor heating.

Specification of the heating circuit pump 240V~

Specification of the contactor:

Heating circuit pump 208/460/575V~

A wiring diagram for a 208/460/575V heating circuit pump shows the pump (A) connected via a contactor/relay (B) to a 208/460/575V/3/60 VAC power supply (C) with disconnect and protection, connecting to the extension kit (D).

Specification of the heating circuit pump 208/460/575V~

Specification switching the contactor:

Rotary Switch S1

An illustration shows the rotary switch S1 on the EM-P1 Extension. A table details the settings for Rotary switch S1 on the mixer extension kit and on the EM-P1 extension based on the heating circuit configuration.

Connecting the PlusBus to the Boiler

A diagram shows the EM-P1 Extension (A) connected via the PlusBus (74) to a heat generator (B). Instructions state to disconnect plug 74 and connect wires directly for certain heat generator terminals.

Refer to Boiler installation and service instructions.

Power Supply

A diagram illustrates the main power supply connection: 120V/60Hz/12A from a wall receptacle, routed through a main disconnect switch, to the EM-P1 Extension (A).

[WARNING] Incorrectly executed electrical installations can result in injuries from electrical current and in equipment damage.

Connect the power supply (see page 4) and implement all grounding measures (e.g. RCD circuit) in accordance with the following regulations:

• In Canada all electrical wiring is to be done in accordance with the latest edition of CSA C22.1 Part 1 and/or local codes. In the U.S. use the National Electrical Code ANSI/NFPA 70. The heating contractor must also comply with both the Standard for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME CSD-1, and the Installation Code for Hydronic Heating Systems, CSA B214-01, where required by the authority having jurisdiction.
• Connection requirements specified by your local power supply utility.
• Protect the power cable with max. 15A.

[WARNING] The absence of component grounding in the system can lead to serious injury from electrical current if an electrical fault occurs. Connect the appliance and pipework to the equipotential bonding of the building in question.

[WARNING] Incorrect core allocation can result in serious injury and damage to the appliance. Never interchange cores "L" and "N".

[CAUTION] An incorrect phase sequence can cause damage to the appliance. Check for phase equality with the power supply connection of the control unit.

Connecting Several Accessories

A diagram shows various accessories (A, B, C, D) connected to the EM-P1 Extension. It indicates that for accessories with higher power demand, the contact output should be used to switch an on-site relay.

Power supply and PlusBus connection

In the following circumstances, use the contact (output) of the accessories only to switch an on-site relay:

An actuator with a higher power demand than the fuse rating required for the accessories, e.g. a circulation pump, is connected to the contact (output) of the accessories.

Wiring Diagram

A detailed internal wiring diagram of the EM-P1 Extension (PCB A1, A2) is shown, including fuse F1, rotary switch S1, various plugs (120V~, P1, P3, 40, 40A), LV connections (PWM1, TS1, TS2, TS3), and the PlusBus connection (74). Electronic components like relays (K1, K2, K3), transformer T1, and capacitor C1 are depicted.

Specifications