How to Use a Stove Manometer

Manometers can indicate whether a leak is present in your stove's gas system.

Though gas stoves offer more control and efficient operation than electric stoves, the threat of a natural gas leak can create a serious safety hazard for occupants. Manometers are measuring devices that gauge air pressure in stoves and ensure that combustion gases are exhausting properly. While most people do not own manometers, these devices are handy for gas stove owners living in rural areas or for technicians who fix gas stoves as part of their profession. The most basic type of manometers feature u-shaped tubes filled partly with water, oil or mercury.

Things You'll Need

• Manometer
• Protective goggles
• Protective gloves
• Wrench
• Soap solution

Instructions

1. Turn off all gas appliances in the kitchen, including your refrigerator. Switch off the pilot light. Be sure to wear protective eyewear and gloves if your stove is using a high-pressure or high-temperature system.

2. Open the valve on the gas tank and use a wrench to pressurize the system. Close the valve.

3. Disconnect the gas line to the stovetop range. Securely connect the manometer hose fitting onto the burner’s gas pressure tap.

4. Gradually open another stovetop burner, which will release initial pressure and provide a more accurate measurement. Keep releasing the pressure until the manometer needle is slightly below full pressure. This will release trapped pressure between the gas tank and regulator.

5. Record the initial reading on the manometer. Note the difference in height between the side where pressure is applied versus the side where liquid is forced up the tube. The sum of the readings below and above the zero mark indicates the pressure level.

6. Wait approximately 20 minutes and return to take a second reading. If the manometer reveals a leak, spray a soap solution consisting of ammonia-free dishwashing liquid and water along joints on the gas supply system. Observe whether bubbles form at the connections; if they do, this confirms that leaks are present.

Tips & Warnings

• Check with your stove’s manufacturer to find out the recommended draft pressure. The manufacturer should also be able to tell you where you should use the manometer to measure pressure levels.

• Because mercury is significantly heavier than water, mercury manometers have low vapor pressure. Likewise, vapor pressure in mercury manometers can usually be ignored except for readings showing extremely low pressure, according to Davidson College.

• Do not use manometers with gas tank systems that exceed the instrument’s maximum pressure specifications.

• Never use the manometer to measure highly flammable, corrosive or hazardous fluids and gases.

• Be sure that the manometer is secured tightly, as loose connections can result in air leakage and possible injury.

References

• RV Mobile Inc: Gas Pressure and the Manometer
• Energy Efficiency Asia: Energy Efficiency Guide for Industry in Asia
• TSI: Hydronic Manometer
• Davidson College: Gas Laws