Novus N321S NTC Differential Temperature Controller for Solar Heating 12-24v (80321S3014)

Intelligent & Reliable Control for Solar Water Heating Systems

Efficient solar heating relies on precise control to ensure the pump only circulates water when the solar collector is hotter than the storage tank. Without a dedicated differential controller, you risk inefficient operation, wasted energy, and potential damage to your system from freezing or overheating. You need a purpose-built solution that provides intelligent, reliable control.

The Novus N321S NTC Differential Temperature Controller (80321S3014) is a purpose-built instrument designed to optimise the performance of solar heating systems. It utilises two NTC-type temperature sensors (one for the collector and one for the tank) to continuously measure the temperature difference. When the collector is warmer, the controller activates a water circulation pump via a powerful 16 A SPDT relay output, ensuring maximum energy transfer.

Beyond simple differential control, the N321S provides critical safety features. It includes configurable functions to protect the piping from damage due to freezing in winter and to prevent overheating that could harm your system. With a wide power supply range of 12-24 Vac/dc, a bright 3½-digit LED display, and robust front-panel protection (IP65), the N321S is a reliable and durable solution for managing your solar heating application.

Key Features & Benefits

• Differential Control for Solar Heating: Specifically designed to manage a water circulation pump based on the temperature difference between a solar collector and a thermal storage tank or swimming pool.

• Dual NTC Sensor Inputs: Comes with two high-accuracy NTC thermistor sensors ($10k\Omega$ @ 25∘C) to provide real-time temperature readings from both the collector and the tank.

• Integrated Safety Functions: Includes configurable anti-freezing and anti-overheating setpoints to protect your system's piping and components from damage.

• High-Power Relay Output: Features a robust 16 A / 1 HP relay (SPDT) to directly control a water circulation pump, eliminating the need for an external contactor in many applications.

• Wide Power Supply Compatibility: Operates on a versatile power supply range of 12 to 24 Vac/dc, making it suitable for a variety of installations.

• Durable & Protected Design: The front panel has an IP65 rating, protecting it from dust and water splashes, while the polycarbonate housing ensures longevity.

• Easy-to-Read Display: The 3½-digit LED display provides a clear and bright indication of temperatures and parameters.

Technical Specifications

• Product Type: Differential Temperature Controller

• Model: N321S

• Part Number: 80321S3014

• Application: Solar Water Heating

• Sensor Inputs: 2 x NTC Thermistor ($10k\Omega$ @ 25∘C)

• Measurement Range: $-50$ to 120∘C ($-58$ to 248∘F)

• Accuracy: ±0.6∘C

• Measurement Resolution: 0.1∘C

• Power Supply: 12 to 24 Vac/dc

• Output: 1 x SPDT Relay, 16 A Resistive ($1$ HP / $250$ Vac)

• Display: 3½-digit LED

• Panel Cutout: 70 x 29 mm

• Dimensions (WxHxD): 75 x 33 x 75 mm

• Weight: 100 g

• Protection Rating: IP65 (Front Panel)

• Operating Temperature: $0$ to 40∘C

• Included Accessories: 2 NTC sensors with 3m cables.

Ideal Applications

The Novus N321S is an essential component for any system requiring precise temperature differential management, including:

• Solar Water Heaters: Activating pumps to transfer heat from collectors to tanks.

• Swimming Pool Heating Systems: Maintaining a consistent pool temperature using solar energy.

• Thermal Storage Systems: Controlling heat transfer between a primary and secondary tank.

• Air Destratification: Can be used to activate fans to circulate air and eliminate heat trapped at the top of a building.

Important Installation & Safety Notice

Installation of this electrical component must be performed by a qualified electrician or technician in strict accordance with all local electrical codes, safety regulations, and the heater manufacturer's instructions. Always ensure the system is disconnected from the main power supply before any work is carried out. Improper wiring or installation can lead to electrical shock, fire, or equipment damage.

Q1: What does "differential temperature control" mean?

A1: Differential temperature control is a method of activating a device (like a pump) only when the temperature difference between two points (e.g., a solar collector and a water tank) reaches a specific, user-defined value.

Q2: Are the temperature sensors included with the unit?

A2: Yes, the Novus N321S (80321S3014) typically comes bundled with two NTC thermistor sensors with 3-meter cables.

Q3: Can I extend the sensor cables?

A3: Yes, the sensor cables can be extended up to 200 meters. Novus recommends using shielded, twisted-pair cables to prevent electrical interference.

Q4: Does this model include RS485 communication?

A4: No, this specific part number (80321S3014) does not include the optional RS485 communication feature. A different part number would be required for that functionality.

Optimise your solar heating system's performance and protect your investment. Order your Novus N321S NTC Differential Temperature Controller today!