This New Years weekend I received a telephone call from a customer who purchased an alternative ventless glass gas fireplace from us a little over a year ago. Her pilot light was burning but she could not get the fireplace to light. She called her installer and he also could not get the fireplace to light. This gas fireplace has an on-off remote controlled valve made by Rasmussen.
Some older gas fireplaces used to have a toggle switch attached to the control valve inside the fireplace. Some more recent fireplaces by R.H. Peterson and Vanguard, Majestic and Superior fireplaces also had toggle switches. The on-off remote control combination of a receiver-transmitter use the same idea as a toggle switch and it is common to replace an old style toggle switch with a receiver box in order to convert a gas log fireplace to a remote controlled unit.
A receiver box acts like the toggle switch turning the fireplace on or off and the hand held transmitter or any other kind of transmitter flips the toggle switch to the “on” or “off” position. The receiver is hard-wired to the fireplace burner control valve and most people leave their receiver inside the fireplace. There is a real danger to overheating a receiver box because the receiver box holds batteries that can be damaged by heat. Often if a fireplace with a remote control will not be controlled by a remote the problem is either low batteries or batteries damaged by heat. If the batteries are damaged by heat while inside the receiver box, inside the fireplace the receiver box is usually irreparably damaged.
The other problem with unvented gas fireplace has to do with the safety features that must be used in every vent-free gas log. The ODS (oxygen depletion sensor) is a very simple function that leaves a thermocouple in the pilot light so the thermocouple will cool and turn off the control valve if the pilot light begins to raise up looking for oxygen to keep it burning. On the sides of any pilot tube are small holes in the pilot light tube that allow oxygen to be sucked into the tube to mix with gas and allow the pilot to burn. Ventless gas fireplaces should be cleaned as part of typical maintenance but when they are not properly cleaned these tiny holes are small enough to be severly clogged by tiny bits of dust, pet hair and pollen in the air.
Usually when our service technicians are called to a home because a vent-free gas fireplace will not properly light this maintenance issue is the problem. We bring a small but powerful vacuum and leave it lying against the pilot assembly to cause flowing air to pull anything from these small air holes. Once it has been vacuumed we may also use a can of compressed air. We do not go to the compressed air can first because we do not want to blow the foreign substance into the pilot assembly.
If the batteries are fully charged or new and the receiver box is not damaged by overheating but the fireplace will not light the next thing to check is the receiver codes. A receiver box will have a “Learn” button on it and sometimes when the batteries are changed or if the power is interrupted by heat the code for the transmitter will need to be relearned. Most received boxes are very versatile and will learn tens of thousands of varying transmitting codes. Hold the Learn button for about 5 seconds until a series of beeps indicates the box is wiped clean and “listening. Then press any button on the transmitter for the receiver to remember the proper code for that transmitting controller.
Finally, this specific fireplace valve uses a solenoid control.
Sometimes it is possible the solenoid has become too strongly attached inside the control valve. This could be caused by over tightening at the original factory, by constant heating an expanding and by a combination of these two causes. The solenoid can be removed with a flat head screwdriver. Reinstall the solenoid “hand-tight” so it is not over tightened in the valve.
The solenoid triggers the switch like an internal toggle switch.
Vent free gas fireplaces have always been a popular commodity but with the alternative gas fireplace that display crushed reflective glass colors, stones, shapes and fireballs ventless gas fireplaces are more popular than ever. The limited BTU’s, control options like the ODS and flame patterns are as important as properly maintaining the fireplace with clean materials and fully charged batteries.
The process for lighting a vent-free gas log fireplace involves holding the control valve open manually until the thermocouple is transferring enough of a charge to pull the control valve magnet into the open position. Soon we will explain the process of the thermocouple to help understand the safety features in your vent free gas fireplace.