Water Heater Models 305 and 505 Service Manual

A technical service manual for Water Heater models 305 and 505, providing troubleshooting guides, error code definitions, wiring diagrams, and component…

Brand: Unknown
Category: Water heater
Document type: Service Manual
Language: English
Pages: 2
File format: PDF
File size: 665 KB
Published: 31 October, 2026
Updated: 31 October, 2026
MD5 checksum: 1DE28ED07DD237E8218EE7D2F6EC254E
PDF: Water Heater Models 305 and 505 Service Manual PDF

About this manual

This document serves as a technical guide for servicing Water Heater models 305 and 505. It details troubleshooting procedures for various error codes, including power interruptions, flame failures, and sensor faults. The manual provides specific diagnostic steps for issues such as no ignition, thermal fuse activation, and combustion fan failure.

What's inside

Error Codes
Troubleshooting
Wiring Diagram
Component Specifications
Safety Notes
Dip Switch Settings
Gas Pressure Settings
Thermistor Resistance
Frost Protection
Flame Rod Testing

Specifications

Default Maximum Temperature	120 °F (49 °C)
Maximum Temperature Option	140 °F (60 °C)
Surge Protector Voltage	108 ~ 132 VAC
Remote Controls Voltage	10 ~ 13 VDC
Combustion Fan Motor Voltage	5 ~ 10 VDC

Frequently asked questions

What are the troubleshooting steps for a power interruption during bath fill?

Turn off all hot water taps and press ON/OFF twice.

How do I set the altitude for the dip switches?

Set switches 2 and 3 in the bank of 8 depending on your altitude according to the table provided.

What is the resistance reading for the frost protection heater on the heat exchanger piping?

The resistance reading should be 156-180 ohms.

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