There are five popular gas control types for gas fireplaces and gas logs
- Manual Control Valve - Manual control log sets are just that; manually controlled. You turn the burners on and can adjust the flame height by a control knob on the gas appliance. This adjusting ability is usually very desirable in a vented log, because the action of a vented log wider and has more of a range of flame height to adjust. (No Standing Pilot) (Natural gas Only)
- Safety Pilot Control Valve - The safety pilot control is a manual control valve with a standing pilot. You turn the burners on and can adjust the flame height by a single control knob on the log set. On an unvented appliance, you manually adjust the flame height in order to control temperature in the room. (Minimum requirement for LPG or Propane gas)
- Millivolt Control Valve - A control valve that allows for the use of a remote control, a wired or wireless wall thermostat or a simple on/off switch. Because they offer this high level of functionality, they are more expensive. Use of a wall-mounted or hand held thermostat cycles the gas on and off, in order to maintain temperature. These are very popular controls for logs. Not too expensive, good accessories available. Flame height is adjusted by turning a knob on the gas appliance only. They can also be used manually. Millivolt (or remote-ready) offers the most overall flexibility as more different types of remote units and switches are available than for any other gas system.
- Variable Control Valve - A Hi/Lo valve control offers flame height control by remote only and usually includes the proper remote. You systematically depress and release the "on/hi" switch on a hand held remote (or remote receiver box) until the flame reaches the desired height. If you want to turn the log set off, you depress and release the "off/lo" switch until the flame turns off. You cannot easily control the log set manually, but it can be done. It does, however, allow flame height control via remote.
- Electronic Ignition Control Valve - Electronic ignition valve systems are the latest technology. These types of systems turn the gas on and off electronically and do not have a standing safety pilot. There is no wasted gas or noise from a gas pilot when the logs are not burning. This is the most expensive type of system, but the most desired. Most electronic ignition systems are packaged with a remote control.