14
P a g e
WHEN REPLACING THE PRESSURE – TEMPERATURE RELIEF VALVE
• DO NOT
install anything less than a combination pressure–temperature relief valve certified
by a nationally recognized testing laboratory that conducts periodic inspections of such
products and certifies them as meeting the requirements for Relief Valves and Automatic Gas
Shutoff Devices for Hot Water Supply Systems, ANSI Z21.22. Valve must have a maximum set
pressure not to exceed 150 psi.
• Install valve into opening provided and marked for this purpose on water heater.
• Installation must conform with local codes or in the absence of local codes, American National
Standard for Recreational Vehicles, ANSI A119.2/NFPA 501C
Functional Description
We include here additional information needed to identify the various components of the system
in order to facilitate communications of the user with Girard Products or an authorized Service
Center for any questions regarding the proper operation of the water heater. The model GSWH-
1M consists of the following main sub-systems and components:
1. Water Sub-System:
1.1. Flow Switch
1.2. Heat Exchanger
1.3. Limit Switch / Emergency Cut-Off (ECO): (Normally closed; open T>131°F)
1.4. P/T Valve: to provide pressure relief in case of overheating
2. Gas Sub-System
2.1. Gas Control Regulator.
2.2. Gas Modulator Valve
2.3. Burner (Blade type; high efficiency)
3. Flue Sub-System
3.1. Flue Collector
3.2. Exhaust Blower
3.3. Flue outlet
4. Electrical Sub-System
4.1. 12VDC connection wires
4.2. Power switch
4.3. Blower Motor
4.4. Microprocessor based Circuit Board (Spark Igniter, Safety and Diagnostics)
4.5. Spark Igniter
4.6. Sail switch to detect air flow at the exhaust.
4.7. Gas Modulator Control (GMC) connection wire
In the following pages we present:
1. Figure 9:
Shows an exploded view of the GSWH-1M water heater with identification labels for
all components.
2. Figure 10:
A wiring diagram with all electrical components showing all interconnections
and the wire colors adopted.
3. Figure 11:
A Circuit Ladder Diagram to illustrate the Control logic and functionality of
each electrical component
