Grundfos 595444 3/4-inch Clip-on Aquastat Kit Instruction Manual

1. Introduction

The Grundfos 595444 3/4-inch Clip-on Aquastat Kit is designed to enhance the efficiency of hot water recirculation systems. This control unit automatically manages the operation of a circulator pump by monitoring the temperature of the hot water line. It activates the circulator when the water temperature falls below 85°F and deactivates it when the temperature exceeds 105°F, ensuring hot water availability while minimizing pump run-time and energy consumption. This aquastat can be used independently or in conjunction with a timer control.

2. Safety Information

WARNING: Electrical Shock Hazard. Always disconnect power before installing or servicing this device.

• Read all instructions carefully before installation and operation.
• Installation must be performed by a qualified electrician or plumber in accordance with local codes and regulations.
• Ensure the power supply to the circulator pump is disconnected before beginning any work.
• Do not operate the device if it appears damaged.
• Keep children away from the installation area.

3. Package Contents

Verify that all components are present before proceeding with installation:

• Grundfos 595444 Clip-on Aquastat Control
• Mounting hardware (if applicable)
• Instruction sheet

4. Setup and Installation

The Grundfos 595444 Aquastat is designed for easy clip-on installation directly onto a 3/4-inch hot water pipe. Follow these steps for proper setup:

1. Identify Installation Location: Select a suitable location on the hot water supply line, typically near the water heater or where the recirculation line returns. Ensure the pipe is clean and free of insulation at the mounting point.
2. Prepare the Pipe: For optimal temperature sensing, ensure the pipe surface where the aquastat will be clipped is clean and free of debris or excessive paint.
3. Attach the Aquastat: Open the clip mechanism on the aquastat. Position the aquastat firmly onto the 3/4-inch pipe, ensuring good contact between the sensor and the pipe surface. Close the clip securely to hold the aquastat in place.
4. Wire the Aquastat: Connect the aquastat's electrical leads to the circulator pump's control circuit. Refer to the wiring diagram provided with your circulator pump and the aquastat for specific connections. Typically, the aquastat acts as a switch in series with the circulator's power supply or control wiring.
5. Restore Power: Once all connections are secure and verified, restore power to the circulator pump system.

Note on Pipe Temperature: The aquastat senses the external temperature of the pipe. Due to heat transfer, the external pipe temperature may be slightly lower than the internal water temperature. This is accounted for in the design, but heavily insulated pipes or specific system configurations might affect perceived temperature readings.

5. Operating Instructions

The Grundfos 595444 Aquastat operates automatically once installed and wired correctly. There are no user-adjustable settings on the device itself.

• When the temperature of the hot water line, as sensed by the aquastat, drops below approximately 85°F, the aquastat will close its internal switch, allowing power to flow to the circulator pump.
• The circulator pump will run, moving hot water through the recirculation loop, until the temperature at the aquastat's location reaches approximately 105°F.
• Once the temperature reaches 105°F, the aquastat will open its internal switch, interrupting power to the circulator pump and turning it off.
• This cycle repeats as needed to maintain hot water in the recirculation line within the specified temperature range.

The aquastat can be used in conjunction with an external timer. If a timer is used, the circulator will only operate when both the timer allows operation AND the aquastat senses a temperature below 85°F.

6. Maintenance

The Grundfos 595444 Aquastat is designed for maintenance-free operation. However, periodic checks are recommended to ensure optimal performance:

• Visual Inspection: Annually inspect the aquastat and its wiring for any signs of physical damage, corrosion, or loose connections.
• Secure Mounting: Ensure the aquastat remains securely clipped to the pipe, maintaining good thermal contact.
• System Performance: Monitor your hot water recirculation system's performance. If you notice inconsistent hot water availability or excessive pump run-time, check the aquastat and circulator for proper function.

CAUTION: Do not attempt to disassemble or repair the aquastat. Refer all servicing to qualified personnel.

7. Troubleshooting

If your hot water recirculation system is not performing as expected with the Grundfos 595444 Aquastat, consider the following:

• Circulator Not Running:
  • Check if the circulator pump has power.
  • Verify that the aquastat is correctly wired to the circulator.
  • Ensure the pipe temperature at the aquastat's location is below 85°F. If the pipe is already warm, the aquastat will keep the circulator off.
  • If using a timer, ensure the timer is in an 'ON' cycle.
• Circulator Running Continuously or Too Long:
  • Check if the aquastat is securely clipped to the pipe and making good thermal contact.
  • Verify that the pipe temperature is reaching 105°F. If the system cannot reach this temperature (e.g., due to poor insulation or insufficient heat input), the aquastat may not turn off the pump.
  • Consider the difference between internal water temperature and external pipe temperature. In some systems, the external pipe may not reach 105°F even if the water inside is hotter, leading to longer run times.
  • Ensure there are no short circuits in the wiring bypassing the aquastat.
• Inconsistent Hot Water:
  • The aquastat's fixed temperature range (85-105°F) may not perfectly suit all system designs or user preferences. If you desire hotter water or a different control range, this aquastat may not be the ideal solution for your specific needs.
  • Check for air in the recirculation lines, which can impede flow and temperature sensing.

If problems persist after checking these points, contact Grundfos customer support or a qualified professional.

8. Specifications

9. Warranty and Support

For specific warranty information regarding your Grundfos 595444 Clip-on Aquastat Kit, please refer to the documentation included with your purchase or visit the official Grundfos website. Grundfos products are typically covered by a manufacturer's warranty against defects in materials and workmanship.

If you require technical assistance, troubleshooting, or have questions about your product, please contact Grundfos customer support:

• Grundfos Official Website: us.grundfos.com
• Refer to your product packaging or the Grundfos website for the most current contact information, including phone numbers and email support.