GAS FIRE PIT
MANUAL IGNITION SYSTEMS
This is the most basic of the Ignition Systems. The user opens the gas valve manually using the gas valve key and lights the burner with a long match or taper. To turn off you simply close the gas valve.
A step up from the match lit system. An ignitor probe is installed next to the burner. It is connected by electrical cable to a push button place on the outer surface of the fire pit structure. The user turns on the gas using the gas valve key and then pushed a button causing the probe to spark igniting the burner. No electrical supply is necessary, the spark is either generated by a Piezo style ignitor or a battery powered system. In most cases, the battery is located inside the button itself for easy replacement.
MANUAL SAFETY PILOT SYSTEM
These safety systems have various names depending on the manufacturer. In essence, it is a failsafe system which cuts off the gas supply in the event that the fire pit place goes out. It can be either match lit or use a spark ignition system.
The pilot and thermocouple are installed close to the burner and to the gas valve. The user depressed and turns the knob to the pilot position. This opens the pilot valve allowing gas to flow. The burner is then lit by a match or spark ignition, and the flow engulfs the thermocouple.
Electricity which is generated by the heat flows to an electromagnet which holds open the pilot valve. The knob is held in until the pilot light remains alight by itself and then it is turned to the on position. The gas then flows to the burner and is lit by the pilot flame.
If the flame should be extinguished, the thermocouple cools (very quickly) the electrical current is no longer generated and the pilot valve snaps shut, cutting off the gas supply to the system. Some systems use the thermocouple directly with the main burner flame, forgoing the pilot altogether.
ELECTRONIC IGNITION SYSTEMS
These are the top of the range of ignition systems. A simple on/off switch is all that is required to light the fire pit, it can even be done via remote control. The sophisticated electronics do the rest. Most systems require a mains electrical feed to the fire pit, but a few use battery power.
There are many different variations of these systems on the market. Some utilize a pilot others do not, some use a thermocouple or thermopile others use a different type of flame sensing system. There are also a variety of ways the burner is lit, for example, Hot Surface and Hot Wire ignitions use an element/wire that heats up to a temperature sufficient to ignite the gas. Spark ignitions use an electrode to do the same thing.
Despite the variety, all these systems basically work in the same way. The user operates the system using a remote control, timer or wall switch. Once ignited the burner will light and as long as a flame is present it will burn until turned off by the user. However, if the flame is extinguished, the system will close off the gas and after about 15 secs. it will start the ignition sequence to relight the burner. If the burner does not relight after about 4 or 5 attempts then the unit will shut off the gas completely.