Rheem RTEX-18 Manual: A Comprehensive Guide
This comprehensive guide details the Rheem RTEX-18‚ covering installation‚ operation‚ maintenance‚ and safety—ensuring efficient‚ on-demand hot water for various applications.
Overview of the Rheem RTEX-18
The Rheem RTEX-18 is a powerful 18kW‚ 240V tankless electric water heater designed for point-of-use or multiple applications. It delivers a consistent 4.4 GPM flow rate of hot water on demand‚ eliminating standby heat loss associated with traditional tank water heaters.
This unit is ideal for situations requiring instant hot water‚ such as under-sink applications‚ showers‚ or supplemental heating. Its compact design facilitates easy installation‚ while robust copper immersion heating elements with brass tops ensure durability and simplified replacement. The digital temperature display allows for precise temperature control‚ enhancing user convenience.
The RTEX-18 provides endless hot water‚ making it a reliable and efficient solution for residential and light commercial settings. Understanding this manual is crucial for safe and optimal performance.
Key Features and Specifications
The Rheem RTEX-18 boasts several key features‚ including its 18kW power rating and 240V electrical requirement. It delivers a flow rate of 4.4 GPM‚ providing a substantial temperature rise. Robust copper immersion heating elements‚ coupled with brass top connections‚ ensure longevity and ease of maintenance through threaded replacement.
A prominent feature is the digital temperature display‚ allowing precise adjustments for customized comfort. The unit supports multiple applications‚ making it versatile for various needs. Its compact size simplifies installation in tight spaces.
Specifications: Voltage – 240V‚ Power – 18kW‚ Flow Rate – 4.4 GPM‚ Heating Element – Copper Immersion‚ Inlet/Outlet – ¾” NPT. This tankless design offers on-demand hot water‚ eliminating standby losses and promoting energy efficiency.
Applications of the RTEX-18 Water Heater
The Rheem RTEX-18 excels in diverse applications requiring on-demand hot water. It’s ideally suited for single point-of-use scenarios like under-sink installations‚ providing instant hot water to kitchens or workshops. Its capacity also extends to multiple applications within a home‚ supporting showers‚ handwashing stations‚ and other fixtures.
This unit is particularly effective for supplemental heating‚ boosting the temperature of existing water heaters during peak demand. It’s a great solution for remote locations or areas where a traditional tank water heater isn’t practical.
Considerations include its suitability for shower applications‚ offering endless hot water when properly sized for the climate and flow rate. The RTEX-18 is a versatile choice for both residential and light commercial settings.
Installation Process
Proper installation is crucial for optimal performance. This involves pre-installation checks‚ electrical and plumbing connections‚ and secure mounting of the RTEX-18 unit.
Pre-Installation Considerations
Before beginning the Rheem RTEX-18 installation‚ carefully review the included manual for crucial details. Assess your existing electrical capacity; this unit requires a dedicated 240V circuit. Confirm adequate water supply pressure‚ as tankless heaters demand a minimum flow rate for activation.
Consider the placement of the unit – proximity to both the electrical panel and the point of use is vital to minimize heat loss and ensure efficient operation. Evaluate the existing plumbing; copper or PEX piping is recommended.
Important: Verify local codes and regulations regarding tankless water heater installations. Some areas may require permits or specific installation practices. Ensure sufficient space around the unit for maintenance and access to components. Finally‚ gather all necessary tools and materials before commencing the installation process to streamline the workflow.
Electrical Requirements & Wiring
The Rheem RTEX-18 demands a dedicated 240V electrical circuit with a minimum amperage rating of 30 amps‚ utilizing a properly sized breaker. Incorrect wiring can lead to malfunction or safety hazards. Refer to the wiring diagram within the manual for precise connection instructions.
Employ appropriately gauged wiring – typically 10 AWG copper wire – to handle the 18kW load. Ensure a secure and compliant grounding connection‚ adhering to local electrical codes. The unit requires a NEMA 6-50R receptacle or direct wiring to a dedicated breaker.
Caution: Always disconnect power at the breaker before commencing any electrical work. Double-check all connections for tightness and proper insulation. If you are uncomfortable with electrical work‚ consult a qualified electrician for safe and correct installation.
Plumbing Connections – Inlet & Outlet
The Rheem RTEX-18 features standard ¾-inch NPT inlet and outlet connections. Before connecting‚ flush the lines to remove debris that could damage the unit. Use Teflon tape on all threaded connections to ensure a watertight seal. The manual specifies bottom inlet/outlet for 18kW models.
Install dielectric unions to prevent galvanic corrosion‚ especially when connecting to copper piping. Ensure proper pipe support to avoid strain on the unit. A pressure relief valve is crucial for safety and should be installed on the outlet side‚ directed towards a safe drain location.
Important: Verify water flow direction‚ indicated by arrows on the unit. Avoid over-tightening connections‚ as this can damage the threads. Regularly inspect plumbing connections for leaks.
Mounting the RTEX-18 Unit
The Rheem RTEX-18 is designed for wall mounting. Ensure the chosen location can support its weight‚ even when filled with water. Use appropriate screws and anchors suitable for the wall material – consult a professional if unsure. Maintain minimum clearances around the unit for service access and ventilation‚ as detailed in the manual.
Mount the unit level to ensure proper operation and prevent internal damage. Avoid mounting in areas exposed to freezing temperatures or direct sunlight. Ensure adequate space for plumbing and electrical connections.
Important: Securely fasten the unit to prevent vibration and noise during operation. Regularly inspect the mounting hardware for tightness and stability.
Operation and Control
The RTEX-18 features a digital temperature display for precise adjustments‚ offering convenient control for single or multiple application usage with power settings.
Digital Temperature Display & Adjustment
The Rheem RTEX-18 boasts a user-friendly digital temperature display‚ allowing for precise and convenient water temperature control. This feature simplifies operation‚ enabling users to easily set their desired hot water temperature. Adjustments are made directly through the unit’s interface‚ providing real-time feedback on the selected temperature.
The digital display clearly shows the current water temperature‚ ensuring accurate monitoring. This is particularly useful for optimizing comfort and energy efficiency. Users can fine-tune the temperature to suit their specific needs‚ whether it’s for a comfortable shower or efficient handwashing. The intuitive controls make temperature adjustments straightforward‚ even for those unfamiliar with tankless water heaters.
Consistent temperature delivery is a key benefit‚ eliminating the temperature fluctuations often associated with traditional tank-style heaters.
Understanding the Power Settings
The Rheem RTEX-18 operates on a 240V electrical supply and features an 18kW power rating‚ delivering substantial heating capacity for on-demand hot water. Understanding the power settings is crucial for optimal performance and preventing electrical overload. The unit doesn’t typically have adjustable power levels in the traditional sense; its high power rating is designed for quick heating.
However‚ the draw of 18kW necessitates a dedicated circuit with appropriate amperage and breaker size – typically a 30-amp breaker. Proper electrical wiring is paramount‚ and consulting a qualified electrician is strongly recommended during installation. The unit’s performance is directly tied to the incoming water temperature and flow rate; higher flow rates may result in a slightly lower output temperature.
Efficient operation relies on matching the heater’s capacity to the application’s demands.
Multiple Application Usage
The Rheem RTEX-18 excels in providing on-demand hot water for various point-of-use applications. It’s suitable for single sinks‚ showers‚ or even multiple fixtures‚ though simultaneous high-demand usage may impact temperature consistency. This unit is often utilized for under-sink hot water heaters‚ offering instant hot water without the standby losses of a traditional tank.
Its compact size makes it ideal for installations where space is limited. While capable of supplying multiple applications‚ consider the combined flow rate requirements. For instance‚ running a shower and a sink concurrently will reduce the available hot water volume at each fixture.
The RTEX-18 is a versatile solution for supplemental heating‚ enhancing convenience in various areas of a home or business.
Maintenance and Troubleshooting
Regular maintenance ensures optimal performance; this section details routine procedures‚ common issue resolutions‚ and instructions for replacing heating elements when needed.
Routine Maintenance Procedures
To maintain peak efficiency and prolong the lifespan of your Rheem RTEX-18‚ regular maintenance is crucial. Periodically inspect the unit for any signs of leaks or corrosion around the plumbing connections.
Flush the unit at least once a year to remove mineral buildup‚ especially in areas with hard water. This prevents scaling on the heating elements‚ ensuring consistent performance. The manual provides detailed flushing instructions.
Check the electrical connections to ensure they remain secure and free from damage. Inspect the wiring for any fraying or loose connections.
Clean the exterior of the unit with a damp cloth to remove dust and debris. Avoid using abrasive cleaners. Following these simple procedures will help keep your RTEX-18 operating reliably for years to come.
Troubleshooting Common Issues
If your Rheem RTEX-18 isn’t heating‚ first check the circuit breaker and ensure it hasn’t tripped. Verify the unit is receiving power. No hot water could also indicate mineral buildup; flushing the unit may resolve this.
Low water flow can be caused by partially closed valves or a clogged inlet filter. Inspect and clean the filter regularly. Insufficient incoming water pressure can also contribute to this issue.
Error codes displayed on the digital temperature display indicate specific problems. Consult the manual for a complete list of error codes and their corresponding solutions.
If issues persist‚ avoid attempting complex repairs yourself. Contact a qualified plumber or electrician for assistance. Always prioritize safety and refer to the manual for detailed troubleshooting guidance.
Replacing Heating Elements
The Rheem RTEX-18 features robust‚ threaded copper immersion heating elements designed for easy replacement. Before starting‚ always disconnect power at the breaker. Drain the unit completely‚ following instructions in the manual.
Using a specialized wrench‚ carefully unscrew the old heating element. Inspect the opening for any mineral buildup and clean thoroughly. Apply Teflon tape to the threads of the new element to ensure a watertight seal.
Screw in the new element‚ tightening securely but avoiding over-tightening. Reconnect the plumbing and restore power. Test the unit to confirm proper operation and check for leaks.
Refer to the wiring diagram in the manual for correct electrical connections. If uncomfortable with electrical work‚ consult a qualified electrician. Proper installation is crucial for safety and performance.
Safety Information
Prioritize safety by adhering to all precautions‚ grounding instructions‚ and warranty guidelines detailed within this manual for the Rheem RTEX-18 water heater.
Important Safety Precautions
Before installing or operating the Rheem RTEX-18‚ carefully read this entire manual. Improper installation or operation can lead to hazardous situations. This unit must be installed by a qualified technician adhering to local codes.
Always disconnect electrical power at the breaker before performing any maintenance or troubleshooting. Never operate the unit if it shows signs of damage. Ensure proper grounding to prevent electrical shock – see grounding instructions.
Hot water can scald; set the temperature to a safe level‚ especially when children or elderly individuals are present. Do not use this water heater for potable water if it has been used with non-potable fluids. Regularly inspect connections for leaks.
This appliance is not intended for use by persons (including children) with reduced physical‚ sensory or mental capabilities‚ or lack of experience and knowledge‚ unless they have been given supervision or instruction concerning use of the appliance by a person responsible for their safety.
Grounding Instructions
Proper grounding is essential for the safe operation of the Rheem RTEX-18. This unit must be connected to a grounded electrical circuit‚ adhering to all local electrical codes. The unit is equipped with a grounding terminal; never connect to a non-grounded outlet.
Verify the electrical supply provides a reliable ground connection. If unsure‚ consult a qualified electrician. Incorrect grounding can result in electrical shock hazard. Use appropriately sized grounding wire as specified in the electrical requirements section of this manual.
Do not attempt to modify the grounding plug or adapter. If an extension cord is necessary‚ use a heavy-duty‚ three-wire cord with a grounding plug. Regularly inspect the grounding connection for corrosion or damage. A faulty ground renders safety features ineffective.
Failure to properly ground this appliance voids the warranty and increases the risk of serious injury or property damage. Always prioritize electrical safety during installation and maintenance.
Warranty Information
Rheem provides a limited warranty on the RTEX-18 tankless electric water heater‚ covering defects in materials and workmanship. The standard warranty period for the tank and heating components is typically ten years‚ while other parts are covered for one year from the date of installation.
Warranty coverage is contingent upon proper installation by a qualified technician‚ adherence to installation instructions‚ and regular maintenance as outlined in this manual. Damage resulting from misuse‚ abuse‚ improper water conditions‚ or unauthorized repairs is not covered.
To make a warranty claim‚ retain your proof of purchase and contact Rheem customer support. Rheem may require inspection of the unit or replacement of defective parts. This warranty gives you specific legal rights‚ and you may have other rights which vary by location.
Please refer to the separate warranty document included with your RTEX-18 for complete details‚ terms‚ and conditions. Registering your product online can streamline the warranty claim process.
Technical Details
This section provides detailed schematics‚ wiring diagrams‚ and performance data for the Rheem RTEX-18‚ aiding qualified technicians in installation and service.
RTEX-18 Wiring Diagram
The RTEX-18 requires a dedicated 240-volt electrical circuit‚ typically utilizing a double-pole breaker with a minimum amperage rating of 30 amps‚ though local codes may dictate higher requirements. Proper wiring is crucial for safe and efficient operation; always disconnect power before commencing any electrical work.
The diagram illustrates the connection points for the incoming power lines (hot‚ neutral‚ and ground)‚ as well as the internal wiring of the unit’s heating elements and control board. Pay close attention to the grounding instructions‚ ensuring a secure connection to prevent electrical shock. Incorrect wiring can lead to malfunction‚ damage to the unit‚ or pose a serious safety hazard. Consult a qualified electrician if you are unsure about any aspect of the wiring process. Refer to the full manual for a detailed‚ color-coded wiring schematic.
Flow Rate and Temperature Rise
The Rheem RTEX-18 boasts a maximum flow rate of 4.4 gallons per minute (GPM)‚ making it suitable for single-fixture applications like point-of-use sinks or showers. However‚ the achievable temperature rise—the difference between the incoming water temperature and the desired hot water temperature—is directly affected by this flow rate.
A higher flow rate will result in a lower temperature rise‚ and vice versa. For example‚ with a typical incoming water temperature of 60°F‚ the RTEX-18 can raise the temperature to approximately 116°F at a flow rate of 4.4 GPM. Reducing the flow rate will increase the temperature rise‚ but may limit the amount of hot water available. Understanding this relationship is key to optimizing performance and ensuring comfortable water temperatures for your specific needs. Refer to the performance charts in the manual for detailed data.