Grundfos ALPHA CS - User Manual

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Overview

ALPHA CS
1. English (US)

The ALPHA CS is a domestic hot-water recirculation system designed to provide instant hot water at the faucet. It's a comfort system with a bypass valve and a thermal actuator, featuring a built-in digital timer that allows scheduling to save energy when hot water isn't required. The system utilizes the existing cold-water supply line as a return line, eliminating the need for a separate return line and electrical power.

Function Description

The ALPHA CS is a hot-water recirculation pump designed to deliver instant hot water to faucets in a home. It operates by circulating hot water through the existing cold-water supply line, effectively turning it into a return line. This eliminates the need for a dedicated return line and simplifies installation, as no electrical power is required under the sink. The pump features a built-in digital timer that allows users to schedule operation, optimizing energy consumption by ensuring hot water is only circulated when needed.

The system includes a bypass valve and a thermal actuator, which work together to regulate water flow and temperature. The digital timer allows for precise scheduling of pump operation, helping to save energy by preventing continuous circulation when hot water is not required. The ALPHA CS is designed for indoor use only and is considered suitable for a hot-water recirculation application where the pump is lubricated and cooled by the liquid being pumped.

The ALPHA CS offers several product features to enhance user experience and energy efficiency:

Integrated digital timer: Eliminates the need for a physical programmable timer.
Homeowner scheduling: Via the Grundfos HOME app, users can easily schedule pump operation.
Plug and play control mode with AUTOADAPT: Simplifies setup and operation.
Easier selection: With the Grundfos GO app, ensuring compatibility checks.
Reduced risk of flow accelerated corrosion: With flow limit.
Reduced fluctuation in shower temperatures: With FLOWSENSE.

Important Technical Specifications

Flow rate (Q): Max. 13.6 gpm (3.1 m³/h)
Head (H): Max. 18 ft (5.5 m)
Supply voltage: 1 x 115 V, ± 10 %, 60 Hz. The pump requires no external motor protection.
Motor protection: No external motor protection.
Power usage (approximate): Min. 2 - max. 38 W
Enclosure class: Indoor use only. Enclosure type 2.
Insulation class: F
Ambient temperature: 32-131 °F (0-55 °C)
Liquid temperature: 36-203 °F (2-95 °C)
Relative humidity: Max. 95 %
Max. outlet pressure: 175 psi (12 bars) (1.2 MPa)
Sound pressure level: < 25 dB(A)
Approvals: cULus and FCC. The product complies to limits for class B digital device, pursuant to Part 15 of the FCC Rules.
Port-to-port length: 5.31" (135 mm)
Pump housing: Stainless steel
Connection type: 3/4" NPT(M) × 3/4" NPT(F)
Connections: Comfort Valve: ½" NPS(M), Flex hose: ½" NPS(F) × ½" NPS(F) × 12"

Inlet pressure:

167 (75) °F: 0.75 (0.05) psi (bar)
203 (95) °F: 7.25 (0.5) psi (bar)
230 (110) °F: 15.7 (1.08) psi (bar)

Usage Features

The ALPHA CS is designed for ease of use and installation. It features a control panel with LED indicators and buttons for various functions.

Operating Panel: The operating panel includes a touchscreen that allows users to change settings and view information.

Grundfos mini Eye: This indicator light shows the operating status of the product.
Connect: If lit, the pump is connected to Grundfos GO via Bluetooth.
Settings for control modes: Use arrows to toggle between control modes.
Control mode: Select the control mode (COMFORT SYSTEM AUTOADAPT).

Light Fields Indication: The LEDs indicate the control mode, setting, and operating status.

Active light fields:
- Grundfos GO: When the pump is set via Grundfos GO, the icon is lit, and the modes and settings on the operating panel are switched off.
- Valve opening: The pump is operating with Comfort Valve mounted in the pipe system and runs in constant curve III with 1 gpm until Comfort Valve closes due to correct temperature.
- Setting 1/2" - constant curve III with 1.5 gpm max. flow rate
- Setting 3/4" - constant curve III with 2.3 gpm max. flow rate
- Setting 1" - constant curve III with 3.8 gpm max. flow rate
- The pump is running.
- Warning
- Alarm

Control Modes: The product can be set to the following control modes via the operating panel:

AUTOADAPT: This mode ensures comfort via temperature-controlled Comfort Valve actuation and is suitable for all hot-water recirculation applications without a dedicated return line. During the first startup, the pump operates at its maximum curve with a flow limit of 1.2 gpm for at least 1 hour. During this initial startup procedure, the pump runs several cycles, each lasting 20 minutes (5 minutes on and 15 minutes standby) until the pump has learned the signature of a closed Comfort Valve based on changes in power and flow. After the first startup, the pump automatically turns off when it detects a closed valve, enabling further energy savings.
Continuous operation - 24/7: This control mode ensures comfort 24/7 through continuous operation in constant curve III with flow limits. The flow limits are based on predefined pipe diameters and flow limits (see below) to reduce flow accelerated corrosion and noise in the system. The predefined flow limits can be changed via Grundfos GO.
- 1/2" (1.5 gpm)
- 3/4" (2.3 gpm)
- 1" (3.8 gpm)
Cycle time control: The pump operates at its maximum curve, and it starts and stops based on time parameters. The default time parameters are 5 minutes on and 15 minutes off. The time parameters are adjustable through Grundfos GO.
Constant curve: The pump operates at a constant curve, which means it runs at a constant speed or power. The pump performance follows the selected constant curve. This control mode is recommended in systems replacing old three-speed circulators where the required performance is known.
Constant pressure: The pump operates at a constant pressure, which means the head is kept constant regardless of changes in the system. The pump performance follows the selected constant pressure curve. This control mode is recommended in systems with multiple risers and thermally actuated balancing valves.
Constant flow: The pump operates at a constant flow in the system, regardless of the head. This control mode is recommended when the pump is externally controlled, for example with an aquastat.

Connecting to Grundfos GO: The Grundfos GO app allows for advanced control and monitoring.

Open Grundfos GO on your smartphone or tablet.
Press the gear icon in the top right side of the screen.
Go to the Factory reset menu and press Reset.
Via the operating panel, press and hold the unit icon for 5 seconds.
Press CONNECT in Grundfos GO. Once the connection is established, the LED is permanently on. Grundfos GO is now loading the data for the product.

Guided Setup: The guided setup helps optimize the system settings.

Follow the guided setup in Grundfos GO.
If you select Use default settings, the pump uses the factory setting, valve mode AUTOADAPT.

Flow Limitation: Set a minimum and maximum flow rate in Grundfos GO. A minimum flow limit can be set to prevent the boiler from overheating. A maximum flow limit can be set to prevent noise in the system.

Trend Data: View trend data in Grundfos GO for the last 10 or 100 on-cycles. An on-cycle is the period from when the pump turns on until it turns off. If the pump runs continuously for more than 24 hours, an on-cycle is registered, and a new on-cycle will start even though the pump has not yet turned off. The 100 cycles view consists of 10 observations where each observation is the average of 10 on-cycles. You can see the following data:

Duration of each on-cycle
Flow
Head
Estimated media temperature

Updating the Software:

Make sure your smart device has sufficient power.
Make sure your smart device is connected to the internet. If there is no internet where the pump is installed, go to step 3 and then follow the instructions in Grundfos GO.
Connect your product to Grundfos GO if it is not already connected. The app automatically checks if the product has the latest software installed. If a newer version is available, the text New software available appears on the dashboard in Grundfos GO. You can also check for software updates in the Settings menu.
Follow the guide in Grundfos GO to install the software update.

Maintenance Features

The ALPHA CS is designed for minimal maintenance, but certain checks and procedures are necessary to ensure optimal performance and longevity.

Receiving the Product: Upon receiving the product, inspect it for any damage.

Crushing of feet: Minor or moderate personal injury. Wear safety shoes when handling the product.
Sharp element: Minor or moderate personal injury. Wear protective gloves.
Make sure that the delivered product corresponds to the order.
Make sure that the voltage and frequency of the product match the voltage and frequency at the installation site.

Installation Requirements:

Radio frequency radiation exposure information (for Canada and US only): This equipment complies with FCC and ISED radiation exposure limits set forth for an uncontrolled environment. This equipment must be installed and operated with a minimum distance of 20 cm (0.66 ft) between the radiator and your body.
Optimal installation and operation:
- To create a flow in the system, the pump needs to neutralize the system head loss before it can create a flow.
- When mounting the pump, ensure the shaft is in a horizontal position to avoid air being trapped inside or bearings being worn out too quickly.
- Make sure that the proper voltage and that the wires are connected properly (black = phase, white = neutral, green or bare copper = ground).
- When using ALPHA COMFORT SYSTEM on larger systems, where you are using two or more comfort valves, make sure that the pipe resistance is the same for all loops; otherwise, the flow will be uneven, and some loops might not function correctly if the hoses from the faucet are 1/2" size, mount the 3/8" x 1/2" adapters supplied with the pump on Comfort Valve.
- Comfort Valve is a thermal valve that regulates its opening degree based on the temperature of the media on the hot side of the valve. Comfort Valve allows for maintaining a desired hot side temperature at Comfort Valve. The temperature is completely regulated by the valve with the pump driving the flow of the supply line with hot water from the heat source.
- When using ALPHA COMFORT SYSTEM on very large systems (pipe 1" and above), it is recommended to make a tee by installation for the pump to avoid a flow restriction through the pump.

Mechanical Installation:

Mounting the product: The arrows on the pump housing indicate the flow direction through the pump.
1. Fit the two gaskets supplied, if applicable, with the pump when you mount the pump in the pipe. Make sure to install the pump with a horizontal motor shaft within ± 5°.
2. Tighten the fittings.
Changing the control box position: The control box can be turned in steps of 90°.
1. Loosen and remove the four screws.
2. Turn the pump head to the desired position.
3. Insert and cross-tighten the screws.
Installation of Comfort Valve:
1. Do not use Teflon tape, pipe joint compound or pipe dope on the valve threads.
2. Tighten the flex hose connections, plus 1/4 turn with a wrench. Overtightening the flex hose connections can result in valve damage, causing the valve to leak and/or localized water damage.
3. When making pipe connections, be sure to follow the pipe manufacturer’s recommendations and all code requirements for pipe material.
4. By plumbing convention, the hot water is on the left side and the cold water on the right side, when looking at the sink. Your pipes may be different.
5. For the greatest effect, Comfort Valve must be located at a faucet with the greatest pipe distance from the hot-water heater. If a household consists of more than one hot-water pipe string, one Comfort Valve must be mounted in each string.
6. Close both the hot-water and cold-water angle stop valves below the sink.
7. Disconnect the risers.
8. Correct installation of thermal bypass valve (mounting hardware not included).
9. Connect the 1/2" x 3/8" flex hoses to the ports on the thermal bypass valve marked HOT IN and COLD IN.
10. Connect the 1/2" hose fitting from the HOT OUT port on the thermal bypass valve to the left side of the faucet.
11. Connect the 1/2" hose fitting from the COLD OUT port on the thermal bypass valve to the right side of the faucet.
12. Connect the 3/8" hose fitting from the HOT IN port on the thermal bypass valve to the left angle stop valve.
13. Connect the 3/8" hose fitting from the COLD IN port on the thermal bypass valve to the right angle stop valve.
14. Open both hot-water and cold-water angle stop valves. Check for leaks.
15. The thermal bypass valve may be mounted to the wall with screws if desired.
Checking for proper pump and bypass valve operation:
1. Close the angle stop valve for the cold water below the sink.
2. Open the cold-water faucet.
3. Check that when you turn on the cold-water faucet, the flow of cold water gradually decreases and stops as the bypass valve closes.
4. Check that when you turn on the hot-water faucet, hot water will flow within seconds.

Electrical Connection:

WARNING: Electric shock. Death or serious personal injury.
- Switch off the power supply before you start any work on the product. Make sure that the power supply cannot be switched on accidentally.
- Connect the product only to a properly grounded receptacle.
- All electrical connections must be carried out by a qualified electrician in accordance with local regulations.
- Use of the product on a circuit equipment with a GFCI can cause improper operation of the GFCI. Consult an electrician and observe all national, state, and local electrical regulations, as applicable.
The pump is electronically protected and therefore requires no external motor protection.
Check that the supply voltage and frequency correspond to the values stated on the nameplate.
Connect the pump to the power supply with the power connector supplied with the pump.

Fault Finding: The ALPHA CS provides fault indications on the pump operating panel via the Grundfos mini Eye, which turns either yellow or red and displays an error code.

Warning indication: Yellow light.
Alarm indication: Red light.

Fault Chart: | Grundfos mini Eye | Code in Grundfos GO | Fault | Remedy The ALPHA CS is a hot-water recirculation pump designed for domestic hot-water systems. It provides instant hot water at the faucet, eliminating the wait for hot water and saving water. The system utilizes the existing cold-water supply line as a return line, removing the need for a dedicated return line and simplifying installation. It also operates without requiring electrical power under the sink.

Function Description

The ALPHA CS is a sophisticated hot-water recirculation pump that ensures immediate hot water availability at all taps in a domestic setting. Its core function is to continuously circulate hot water through the existing cold-water supply line, which effectively transforms into a return line. This innovative approach negates the necessity for a separate, dedicated return line, significantly simplifying the installation process and reducing plumbing complexity. Furthermore, the pump's design allows it to operate without requiring an electrical outlet directly under the sink, offering greater flexibility in placement.

A key feature of the ALPHA CS is its built-in digital timer. This intelligent timer enables users to program specific operating schedules for the pump. By activating the pump only during periods when hot water is typically needed, the system optimizes energy consumption, preventing unnecessary circulation and heat loss. This contributes to both energy savings and reduced utility bills.

The system incorporates a bypass valve and a thermal actuator. These components work in conjunction to regulate the flow and temperature of the circulating water. The bypass valve ensures that cold water is not inadvertently drawn into the hot water line, while the thermal actuator monitors water temperature and adjusts circulation as needed to maintain desired hot water levels.

The ALPHA CS is specifically designed for indoor use and is suitable for hot-water recirculation applications where the pump is lubricated and cooled by the water it circulates. This ensures efficient and reliable operation.

The product offers several advanced features to enhance user convenience and system efficiency:

Integrated digital timer: This eliminates the need for external, physical programmable timers, streamlining the system's control.
Homeowner scheduling via the Grundfos HOME app: Users can easily set and modify pump operating schedules directly from their smartphone or tablet, providing intuitive control and flexibility.
Plug and play control mode with AUTOADAPT: This feature simplifies initial setup and ongoing operation. The AUTOADAPT function intelligently learns the household's hot water usage patterns and adjusts pump operation accordingly, optimizing comfort and energy efficiency without manual intervention.
Easier selection with the Grundfos GO app: The Grundfos GO app facilitates product selection and ensures compatibility checks, making it easier for installers and users to configure the system correctly.
Reduced risk of flow accelerated corrosion with flow limit: The system incorporates a flow limit mechanism that helps prevent excessive water velocity, thereby reducing the risk of flow-accelerated corrosion within the plumbing system and extending its lifespan.
Reduced fluctuation in shower temperatures with FLOWSENSE: The FLOWSENSE technology helps maintain consistent water temperatures, particularly in showers, by intelligently managing water flow and preventing sudden temperature changes. This enhances user comfort and satisfaction.

Important Technical Specifications

The ALPHA CS boasts robust technical specifications designed for reliable and efficient performance in domestic hot-water recirculation systems:

Flow rate (Q): The pump can deliver a maximum flow rate of 13.6 gallons per minute (gpm) or 3.1 cubic meters per hour (m³/h). This ensures sufficient hot water delivery for typical household demands.
Head (H): It can achieve a maximum head of 18 feet (5.5 meters), indicating its ability to overcome resistance in the plumbing system and circulate water effectively.
Supply voltage: The pump operates on a single-phase alternating current (AC) supply of 115 volts (V), with a tolerance of ±10%, at a frequency of 60 Hertz (Hz).
Motor protection: The pump features integrated electronic motor protection, eliminating the need for external motor protection devices and simplifying installation.
Power usage (approximate): The power consumption is highly efficient, ranging from a minimum of 2 watts (W) to a maximum of 38 watts (W), depending on the operating mode and demand.
Enclosure class: It is designed for indoor use only and has an enclosure type of 2, indicating its level of protection against solid foreign objects and water ingress.
Insulation class: The pump has an insulation class of F, signifying its ability to withstand higher operating temperatures.
Ambient temperature: The permissible ambient temperature range for operation is 32-131 °F (0-55 °C), making it suitable for typical indoor environments.
Liquid temperature: The pump can handle liquid temperatures ranging from 36-203 °F (2-95 °C), accommodating standard domestic hot water temperatures.
Relative humidity: It can operate in environments with a maximum relative humidity of 95%.
Max. outlet pressure: The maximum outlet pressure is 175 psi (12 bars) or 1.2 MPa, ensuring the system can handle typical domestic water pressures.
Sound pressure level: The pump operates quietly, with a sound pressure level of less than 25 dB(A), minimizing noise disturbance in the home.
Approvals: The ALPHA CS holds cULus and FCC approvals, confirming its compliance with relevant safety and electromagnetic compatibility standards. Specifically, it complies with Class B digital device limits as per Part 15 of the FCC Rules.
Port-to-port length: The physical length of the pump from port to port is 5.31 inches (135 mm), which is important for plumbing layout and installation.
Pump housing: The pump housing is constructed from stainless steel, ensuring durability and resistance to corrosion.
Connection type: The standard connection type is 3/4" NPT(M) × 3/4" NPT(F), facilitating easy integration into existing plumbing systems.
Connections: The system includes specific connections for the Comfort Valve (½" NPS(M)) and flexible hoses (½" NPS(F) × ½" NPS(F) × 12"), providing comprehensive installation components.

Inlet pressure: The maximum permissible inlet pressure varies with liquid temperature:

At 167 °F (75 °C), the maximum inlet pressure is 0.75 psi (0.05 bar).
At 203 °F (95 °C), the maximum inlet pressure is 7.25 psi (0.5 bar).
At 230 °F (110 °C), the maximum inlet pressure is 15.7 psi (1.08 bar). These specifications are crucial for ensuring safe and effective operation under varying system conditions.

Usage Features

The ALPHA CS is designed with user-friendliness and intuitive operation in mind, featuring a clear control panel and smart app integration.

Operating Panel: The pump's operating panel is equipped with a touchscreen interface that allows users to easily view system information and adjust settings.

Grundfos mini Eye: This indicator light serves as a visual cue for the pump's operational status. Different colors or patterns may indicate normal operation, warnings, or alarms.
Connect: When this indicator is lit, it signifies that the pump is successfully connected to the Grundfos GO app via Bluetooth, enabling remote control and monitoring.
Settings for control modes: Dedicated arrow buttons allow users to navigate through and select different control modes, tailoring the pump's operation to their specific needs.
Control mode: This section displays the currently active control mode, such as COMFORT SYSTEM AUTOADAPT, providing immediate feedback on the pump's operational strategy.

Light Fields Indication: The control panel features various LED indicators that provide detailed information about the pump's status, selected settings, and active control modes.

Active light fields:
- Grundfos GO: When the pump is configured and controlled through the Grundfos GO app, this icon illuminates, and the physical buttons and settings on the operating panel are automatically deactivated to prevent conflicting inputs.
- Valve opening: This indicator lights up when the pump is actively operating with the Comfort Valve installed in the pipe system. It signifies that the pump is running in constant curve III mode, circulating water at 1 gpm until the Comfort Valve closes upon reaching the desired temperature.
- Setting 1/2" - constant curve III with 1.5 gpm max. flow rate: This specific setting indicates operation in constant curve III mode with a maximum flow rate of 1.5 gallons per minute, typically used for smaller pipe diameters.
- Setting 3/4" - constant curve III with 2.3 gpm max. flow rate: This setting denotes operation in constant curve III mode with a maximum flow rate of 2.3 gallons per minute, suitable for medium pipe diameters.
- Setting 1" - constant curve III with 3.8 gpm max. flow rate: This setting corresponds to operation in constant curve III mode with a maximum flow rate of 3.8 gallons per minute, designed for larger pipe diameters.
- The pump is running: A dedicated indicator confirms that the pump is actively circulating water.
- Warning: This light illuminates to signal a minor issue or condition that requires attention but does not immediately halt pump operation.
- Alarm: This light indicates a more critical fault that may require immediate intervention and could lead to pump shutdown.

Control Modes: The ALPHA CS offers a variety of control modes to suit different household needs and preferences, configurable via the operating panel or the Grundfos GO app:

AUTOADAPT: This intelligent mode is the cornerstone of the ALPHA CS's efficiency. It ensures optimal comfort through temperature-controlled Comfort Valve actuation. It is ideal for all hot-water recirculation applications that do not have a dedicated return line. During the initial startup phase, the pump operates at its maximum curve with a flow limit of 1.2 gpm for at least one hour. Over this period, the pump executes several learning cycles, each consisting of 20 minutes (5 minutes on and 15 minutes standby). Through these cycles, the pump learns the unique "signature" of a closed Comfort Valve based on changes in power and flow. After this initial learning phase, the pump automatically turns off when it detects a closed valve, leading to significant energy savings.
Continuous operation - 24/7: This mode provides constant comfort by ensuring continuous operation in constant curve III with predefined flow limits. These flow limits are based on pipe diameters and are designed to reduce flow-accelerated corrosion and minimize noise in the system. The predefined flow limits can be customized via the Grundfos GO app for 1/2" (1.5 gpm), 3/4" (2.3 gpm), and 1" (3.8 gpm) pipe sizes.
Cycle time control: In this mode, the pump operates at its maximum curve, but its activation and deactivation are governed by programmed time parameters. The default settings are 5 minutes on and 15 minutes off, but these can be adjusted through the Grundfos GO app to match specific schedules.
Constant curve: This mode maintains a constant pump speed or power, meaning the pump's performance follows a selected constant curve. This mode is recommended for systems replacing older three-speed circulators where a known performance level is desired.
Constant pressure: The pump maintains a constant pressure regardless of changes in the system's head. Its performance adheres to a selected constant pressure curve. This mode is particularly suitable for systems with multiple risers and thermally actuated balancing valves, ensuring consistent water pressure throughout the house.
Constant flow: In this mode, the pump maintains a constant flow rate irrespective of the system head. This is recommended when the pump is externally controlled, for example, by an aquastat, to ensure a steady flow of hot water.

Connecting to Grundfos GO: The Grundfos GO app provides advanced control and monitoring capabilities for the ALPHA CS.

Open Grundfos GO: Launch the app on your smartphone or tablet.
Access settings: Tap the gear icon located in the top right corner of the screen.
Factory reset (if needed): Navigate to the Factory reset menu and press Reset to clear previous settings.
Activate pairing on pump: On the pump's operating panel, press and hold the unit icon for 5 seconds.
Connect in app: In the Grundfos GO app, press CONNECT. Once a successful connection is established, the LED on the pump will illuminate steadily. The app will then proceed to load the product's data.

Guided Setup: The Grundfos GO app offers a guided setup process to help users optimize system settings.

Follow the step-by-step instructions within the Grundfos GO app.
If Use default settings is selected, the pump will automatically configure itself to the factory settings, including the AUTOADAPT valve mode.

Flow Limitation: Users can set both minimum and maximum flow rates via the Grundfos GO app. A minimum flow limit helps prevent the boiler from overheating, while a maximum flow limit can be set to reduce noise in the system.

Trend Data: The Grundfos GO app allows users to view historical trend data for the last 10 or 100 on-cycles. An "on-cycle" is defined as the period from when the pump starts until it stops. If the pump runs continuously for more than 24 hours, a new on-cycle is registered. The 100-cycle view displays 10 observations, each representing the average of 10 on-cycles. The following data points are available:

Duration of each on-cycle
Flow
Head
Estimated media temperature This data can be used for system optimization and fault finding.

Updating the Software: Keeping the pump's software up to date ensures optimal performance and access to new features.

Ensure device power: Make sure your smart device has sufficient battery power.
Internet connection: Verify that your smart device is connected to the internet. If there's no internet connection at the pump's location, proceed to step 3 and follow the instructions in Grundfos GO.
Connect to Grundfos GO: Connect your product to the Grundfos GO app if it's not already connected. The app will automatically check for the latest software. If an update is available, the text New software available will appear on the dashboard. Software updates can also be checked in the Settings menu.
Follow update guide: Follow the instructions in the Grundfos GO app to install the software update.

Maintenance Features

The ALPHA CS is designed for durability and minimal maintenance, but adherence to specific procedures during installation and troubleshooting is crucial for its long-term performance and safety.

Receiving the Product: Upon delivery, a thorough inspection of the product is essential to identify any potential damage or discrepancies.

Crushing of feet: Be cautious of potential minor or moderate personal injury from crushing hazards. Always wear safety shoes when handling the product to protect your feet.
Sharp element: Watch out for sharp edges or components that could cause minor or moderate personal injury. Wear protective gloves during handling to prevent cuts or abrasions.
Order verification: Confirm that the delivered product matches the specifications of your order to avoid installation issues.
Electrical compatibility: Verify that the pump's specified voltage and frequency are compatible with the electrical supply at the installation site. This prevents electrical damage and ensures safe operation.

Installation Requirements: Proper installation is critical for the ALPHA CS to function correctly and safely.

Radio frequency radiation exposure information (for Canada and US only): This device complies with FCC and ISED regulations regarding radio frequency radiation exposure. To ensure compliance and minimize exposure, the equipment must be installed and operated with a minimum separation distance of 20 cm (0.66 ft) between the radiator (the pump) and any person's body.
Optimal installation and operation:
- System head loss: For effective circulation, the pump must first overcome any existing system head loss before it can generate flow.
- Shaft orientation: When mounting the pump, ensure that the motor shaft is positioned horizontally within a ±5° tolerance. This prevents air from becoming trapped inside the pump and reduces wear on the bearings, extending the pump's lifespan.
- Electrical wiring: Confirm that the electrical wiring is correct: black for phase, white for neutral, and green or bare copper for ground. Incorrect wiring can lead to electrical hazards or pump malfunction.
- Multi-valve systems: In ALPHA COMFORT SYSTEM installations with multiple Comfort Valves, ensure that the pipe resistance is uniform across all loops. Uneven resistance can lead to imbalanced flow and inefficient operation of some loops. If using 1/2" hoses, install the supplied 3/8" x 1/2" adapters on the Comfort Valve.
- Comfort Valve function: The Comfort Valve is a thermal valve that regulates its opening based on the temperature of the water on the hot side. It maintains a desired hot side temperature by adjusting flow, with the pump driving hot water from the heat source.
- Large systems (1" pipes and above): For larger systems, it is recommended to install a tee connection for the pump to prevent flow restriction through the pump itself, ensuring optimal performance.

Mechanical Installation: Precise mechanical installation is key to the pump's efficiency and longevity.

Flow direction: The pump housing has arrows indicating the correct flow direction. Ensure the pump is installed in alignment with the system's flow.
1. Gasket installation: Before mounting the pump in the pipe, install the two supplied gaskets. Ensure the pump's motor shaft is horizontal within ±5° to prevent operational issues.
2. Fittings: Securely tighten all fittings to prevent leaks.
Changing the control box position: The control box can be rotated to optimize visibility and access.
1. Loosen screws: Unscrew the four retaining screws on the control box.
2. Rotate pump head: Carefully turn the pump head to the desired orientation in 90° increments.
3. Secure screws: Reinsert and cross-tighten the four screws to secure the control box in its new position.
Installation of Comfort Valve:
1. Thread sealant: Do not use Teflon tape, pipe joint compound, or pipe dope on the valve threads. These can interfere with the valve's operation.
2. Flex hose connections: Tighten flex hose connections with a wrench, then add an additional 1/4 turn. Over-tightening can damage the valve and cause leaks.
3. Pipe connections: Follow the pipe manufacturer's recommendations and all local code requirements for pipe material.
4. Hot/cold water orientation: By plumbing convention, the hot water line is typically on the left, and the cold water line on the right when facing the sink. Verify your specific plumbing configuration.
5. Comfort Valve placement: For maximum effectiveness, the Comfort Valve should be installed at the faucet furthest from the hot-water heater. In multi-string households, each string should have a Comfort Valve.
6. Shut-off valves: Close both the hot-water and cold-water angle stop valves located under the sink.
7. Disconnect risers: Disconnect the existing risers from the faucet.
8. Thermal bypass valve installation: Ensure correct installation of the thermal bypass valve (mounting hardware not included).
9. Hose connections (Hot In/Cold In): Connect the 1/2" x 3/8" flex hoses to the ports marked HOT IN and COLD IN on the thermal bypass valve.
10. Hose connections (Hot Out/Cold Out): Connect the 1/2" hose fitting from the HOT OUT port to the left side of the faucet and the 1/2" hose fitting from the COLD OUT port to the right side of the faucet.
11. Angle stop valve connections: Connect the 3/8" hose fitting from the HOT IN port to the left angle stop valve and the 3/8" hose fitting from the COLD IN port to the right angle stop valve.
12. Open valves and check for leaks: After all connections are made, open both hot-water and cold-water angle stop valves and thoroughly check for any leaks.
13. Wall mounting: The thermal bypass valve can optionally be mounted to the wall using screws.
Checking for proper pump and bypass valve operation: After installation, perform these checks:
1. Close cold water angle stop valve: Close the angle stop valve for the cold water under the sink.
2. Open cold water faucet: Open the cold-water faucet.
3. Observe flow: The flow of cold water should gradually decrease and stop as the bypass valve closes.
4. Check hot water flow: Open the hot-water faucet; hot water should flow within seconds.

Electrical Connection: Electrical connections must be performed with utmost care to ensure safety and prevent damage.

WARNING: Electric shock.
- Power supply: Always switch off the main power supply to the pump before performing any work. Ensure it cannot be accidentally switched back on.
- Grounding: The product must be connected to a properly grounded receptacle to prevent electric shock.
- Qualified electrician: All electrical connections must be carried out by a qualified electrician in accordance with local and national regulations.
- GFCI compatibility: If the product is used on a circuit equipped with a Ground Fault Circuit Interrupter (GFCI), consult an electrician to ensure proper operation and compliance with all applicable regulations.
Motor protection: The pump has integrated electronic protection, eliminating the need for external motor protection devices.
Voltage and frequency: Verify that the supply voltage and frequency match the specifications on the pump's nameplate.
Power connector: Connect the pump to the power supply using the power connector provided with the pump.

Fault Finding: The ALPHA CS incorporates a fault indication system to help users identify and resolve issues.

Fault indication on the pump operating panel: The Grundfos mini Eye indicator light will turn yellow for warnings or red for alarms, displaying an error code.
- Warning indication: A yellow light indicates a minor issue.
- Alarm indication: A red light signifies a more critical fault that may require immediate attention.

Fault Chart: The manual provides a comprehensive fault chart with specific codes and remedies:

| Grundfos mini Eye | Code in Grundfos GO | Fault | Remedy ALPHA CS Installation and operating instructions

ALPHA CS

English (US)

Installation and operating instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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