1. Introduction
This manual provides detailed instructions for the installation, operation, maintenance, and troubleshooting of the Hicello 700 Series Millivolt Gas Valve. This valve is designed as a replacement part for various gas fryers and griddles, offering reliable control over gas flow to the main burner and pilot.
The Hicello 700 Series Millivolt Gas Valve is compatible with Robertshaw 700 series millivolt safety gas valves, including models 700-506, 700-503, 700-502, and 700-504. It is suitable for use with Natural, Manufactured, Mixed, LPG, and LPG/Air Mixtures, making it a versatile component for commercial kitchen equipment.
Figure 1: Hicello 700 Series Millivolt Gas Valve with included reducer bushings.
2. Specifications
The Hicello 700 Series Millivolt Gas Valve features robust specifications designed for reliable performance in demanding environments.
Figure 2: Detailed product specifications.
| Feature | Specification |
|---|---|
| Pressure Regulation | 4" WC Natural Gas |
| Inlet/Outlet Size | 3/4"-14 NPT Female Thread |
| Pilot Outlet | 1/4" Tubing |
| Ambient Temperature Range | -40°F to 175°F |
| Maximum Inlet Pressure | 13.8" WC (0.5 PSI) |
| Valve Opening Style | Fast |
| Capacity | 300,000 BTU |
| Maximum Usage | 720,000 BTU |
| Constant Flame Outlet Thread | 7/16"-24UXS |
| Wireless Functionality | No |
| Battery Included | No |
| Dimensions (L x W x H) | 29 cm x 20 cm x 18 cm |
| Weight | 0.999 kg |
Figure 3: Product description highlighting intake and outlet ends.
3. Package Contents
Upon opening the package, ensure all items listed below are present and undamaged:
- 1 x 700 Series Millivolt Gas Valve Replacement Part
- 2 x Additional 3/4" x 1/2" Reducer Bushing Kits
Figure 4: Contents included in the package.
4. Installation and Setup
WARNING: Installation of gas appliances should only be performed by qualified and licensed professionals. Improper installation can lead to gas leaks, fire, explosion, or serious injury. Always shut off the main gas supply before beginning any installation or maintenance.
4.1 Safety Precautions
- Ensure the main gas supply to the appliance is turned off.
- Disconnect electrical power to the appliance.
- Wear appropriate personal protective equipment (PPE).
- Have a gas leak detector or soap solution readily available for leak testing.
4.2 Replacing the Gas Valve
- Disconnect Old Valve: Carefully disconnect the gas lines (inlet, outlet, pilot) and electrical wiring from the existing gas valve. Note the orientation and connections for proper reinstallation.
- Remove Old Valve: Unmount the old gas valve from the appliance.
- Prepare New Valve: The Hicello 700 Series valve has 3/4"-14 NPT female threads for inlet and outlet. If your appliance requires 1/2" connections, use the provided 3/4" x 1/2" reducer bushing kits. Apply appropriate thread sealant to all pipe connections.
- Install Pilot Outlet: Insert the 1/4" tubing for the pilot gas line into the designated pilot outlet on the valve. Ensure a secure, leak-free connection. Refer to Figure 5 for visual guidance.
- Mount New Valve: Securely mount the new Hicello 700 Series Millivolt Gas Valve in the same position as the old valve.
- Connect Gas Lines: Connect the main gas inlet and outlet lines to the valve. Connect the pilot gas line. Ensure all connections are tight and properly sealed.
- Connect Wiring: Connect the millivolt wiring from the appliance's thermostat and thermopile to the designated terminals on the valve (TH, TP, TH/TP). Refer to Figure 6 for terminal locations.
- Leak Test: Turn on the main gas supply. Apply a soap solution to all gas connections and check for bubbles, which indicate a leak. If leaks are detected, immediately shut off the gas supply and tighten connections until no leaks are present.
- Restore Power: Reconnect electrical power to the appliance.
Figure 5: Installation of pilot outlet and reducer bushings.
Figure 6: Close-up view of the pilot outlet connection.
5. Operation
The 700 Series Millivolt Gas Valve operates with a simple three-position dial: OFF, PILOT, and ON.
Figure 7: Top view of the gas valve showing the control dial.
5.1 Lighting the Pilot
- Ensure the main gas supply is on.
- Turn the control dial to the PILOT position.
- Press and hold the control dial down to allow gas to flow to the pilot.
- While holding the dial down, use a long lighter or match to ignite the pilot flame.
- Continue to hold the dial down for approximately 30-60 seconds after the pilot lights to allow the thermopile to heat up and generate sufficient millivoltage.
- Release the dial. The pilot flame should remain lit. If it extinguishes, repeat the process.
5.2 Turning On the Main Burner
- Once the pilot is lit and stable, turn the control dial from the PILOT position to the ON position.
- The main burner should now ignite when the appliance's thermostat calls for heat.
5.3 Turning Off the Appliance
- To turn off the main burner, set the appliance's thermostat to its lowest setting or turn it off.
- To turn off both the main burner and the pilot, turn the control dial on the gas valve to the OFF position.
6. Maintenance
Regular maintenance ensures the longevity and safe operation of your gas valve.
- Periodic Inspection: Regularly inspect all gas connections for signs of leaks using a soap solution. Check for any visible damage or corrosion on the valve body and gas lines.
- Pilot Filter: The valve includes a pilot gas filter. If the pilot flame becomes weak or inconsistent, the filter may need cleaning or replacement. This should be done by a qualified technician.
- General Cleaning: Keep the exterior of the gas valve clean and free from grease or debris. Do not use harsh chemicals that could damage the valve's components.
7. Troubleshooting
Here are some common issues and their potential solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Pilot will not light or stay lit | No gas supply; Clogged pilot orifice/filter; Faulty thermopile; Insufficient holding time during pilot lighting. | Check gas supply; Clean or replace pilot orifice/filter; Test/replace thermopile; Hold dial down for 30-60 seconds. |
| Main burner does not ignite | Pilot not lit; Thermostat not calling for heat; Faulty main burner solenoid; Insufficient millivoltage from thermopile. | Light pilot; Check thermostat setting; Test/replace main burner solenoid; Check thermopile output. |
| Inconsistent or weak flame | Low gas pressure; Partially clogged lines/orifices; Incorrect pressure regulation. | Verify gas pressure (4" WC for Natural Gas); Clean lines/orifices; Check pressure regulator setting. |
| Gas leak detected | Loose connections; Damaged seals. | Immediately shut off gas supply. Tighten all connections. Replace damaged seals or components. Re-test. |
7.1 Gas Type Compatibility
This valve is designed for use with Natural Gas, Manufactured Gas, Mixed Gas, LPG (Liquefied Petroleum Gas), and LPG/Air Mixtures. Always ensure the gas type supplied to your appliance matches the valve's capabilities and that any necessary conversions or adjustments are made by a qualified technician.
7.2 Voltage Requirements
The 700 Series Millivolt Gas Valve operates on a millivolt system, which generates its own electrical power from the heat of the pilot flame acting on a thermopile. Therefore, no external voltage supply is typically required for the valve itself. Ensure all millivolt wiring connections are secure and free from corrosion.
8. User Tips
- Professional Installation: For safety and optimal performance, it is highly recommended to have this gas valve installed by a certified gas technician.
- Check Package Contents: Upon receiving your order, carefully inspect the package and its contents to ensure everything is present and undamaged.
- Gas Type Verification: Before installation, always confirm that the gas type (Natural Gas, LPG, etc.) used in your appliance is compatible with this valve.
- Millivolt System Awareness: Remember that this is a millivolt system. The valve generates its own power from the pilot flame, so do not attempt to connect external high-voltage power directly to the valve's control terminals.
9. Warranty and Support
9.1 Limited Warranty
This product comes with a 12-month manufacturer's limited warranty for defective items, starting from the date of receipt. This warranty does not cover items damaged due to misuse, improper installation, or unauthorized modifications after receipt. Accessories included with the product are covered by a 3-month warranty.
Defective items must be reported and returned within the warranty period, in their original packaging if possible. You must provide details of the defect and your order number. Repairs or replacements will not be provided for items with an expired warranty.
9.2 Technical Support
For technical assistance, questions, or warranty claims, please contact the seller directly through the platform's messaging system. Support is typically available during business hours, Monday to Saturday, 9:00 a.m. to 6:00 p.m. (GMT+8).