As mentioned earlier, a blue flame is produced when the burner gets the right amount of primary air mixed in with gas. This actually indicates that the burner is operating at maximum efficiency. In contrast, when not enough primary air is supplied to the burner, there is incomplete combustion and so the flame will exhibit what’s known as Yellow-Tipping (or Yellow Flames). Yellow Flames do not burn hot enough and so burner efficiency is actually reduced. This condition produces soot which can blacken surfaces that the flames touch (like pots and pans) or even clog a furnace’s flues or exhaust channels. This clogging can add to further incomplete combustion. Yellow-Tipping can be corrected by adjusting the air shutter until a pure blue flame is produced.

It should be noted that when adjusting the flow of primary air to eliminate the problems previously discussed (Lifting Flames, Flashback, or Extinction Pop), the technician needs to closely observe the color of the burner flame so that correcting one problem doesn’t create a new one, in this case, Yellow-Tipping. Likewise, when adjusting the primary air flow to eliminate Yellow-Tipping make sure that it does not cause Lifting Flames, Flashback or Extinction Pop.

Unstable or Wavering Flames may just be caused by an external draft blowing across the burner which usually affects the pilot or igniting flame. Adding adequate protection or shielding will remedy the situation. However, if the burner’s main flame is unstable, this leads to incomplete combustion. There could also be a crack in the heat exchanger through which the draft passes. Such damages may be detected visually. Maintenance personnel will often look for soot and other types of discoloration to reveal these cracks. In this case, the heat exchanger needs to be repaired or replaced immediately.

An oven or furnace operator should be able to recognize the signs and symptoms of burner problems as this will help a great deal during troubleshooting and repair by maintenance personnel and qualified service technicians.

In this series we will discuss burner problems, their associated symptoms, and possible effects if not properly addressed. Almost all of these symptoms can be recognized by observing flame behavior, shape, color, and distinct sounds, during operation. The recommended procedures to correct these burner problems are also included for reference.

Lifting Flames, as the name suggests, describes how part of the flame seems to lift or “dance” at a considerable distance above a portion of the burner. Normally, a cone of flame will stabilize near the burner port. However, when the velocity of gas-in-air flow is greater than the flame velocity, this lifting will occur, accompanied by a roaring sound. If left unchecked, the cones of flame could break completely, allowing unburned gas to escape, thus reducing the efficiency of the burner. Decreasing the burner’s primary air will usually solve Lifting Flames. Keep in mind that when the burner gets enough primary air, it will produce a conical blue flame.

Flashback is the igniting of the gas-air mixture while still inside the burner orifice or opening. This premature combustion produces a blowtorch-like noise and should be addressed immediately because it will produce carbon monoxide, a colorless, odorless, tasteless and highly toxic gas, as well as other aldehydes. Over time, a Flashback problem will cause the over-accumulation of soot inside the burner and will lead to irreparable damage. As with Lifting Flames, decreasing primary air in the burner will correct the problem. When Flashback occurs in multi-section furnaces that use an array of burners, check the size of the troublesome burner’s orifice against those of the others. If there is some difference, then the burner needs to be replaced. Valve leaks may also cause Flashback. Check and replace them if needed.

Have you been experiencing problems with your electrical equipment and appliances lately?

If your business uses electrical equipment, do circuit breakers trip frequently?

Do motors and other components overheat and burn out?

Do you notice that lights flicker and dim when you start using other electrical appliances at home?

Electrical loads have to be balanced based on the power that they require. The objective of balancing electrical load within a particular circuit is to achieve stability throughout the entire system.

Replacing a blown fuse or resetting a tripped breaker might seem to be all that needs to be done to fix your problem. However, use of these quick fixes is only a band aide solution, you need to have your electrical system checked for proper load balancing. If there is a prevailing imbalance or overload in the circuit, affected devices will continuously exhibit some sort of abnormal behavior and will eventually break down or have a shortened service life.

Left unchecked, you incur relatively larger losses because of electrical overloads. Again, if you are in business, this may be in terms of production downtime and the eventual need to replace damaged equipment. As a homeowner, the replacement of a single blown fuse may not amount to much but it will become a big deal when appliances become damaged.

If you believe that your equipment, devices and tools are in good working order then you might have a problem with how these loads are distributed. Load distribution pertains to how electrical equipment and devices are located with respect to the actual design of an electrical circuit.

Consider the electrical installation for your plant, office building or home. The size of wires for distributing power should be such that, even at full load, they will deliver a steady flow of current to each piece of equipment or device within your circuit. Similarly, the placement of loads should be such that, even during simultaneous operation, each receives an adequate amount of power to keep it running smoothly.

A professional electrician will use proper equipment to check power consumption for each load in the system. Ideally, there should be almost equal or identical consumption for each branch of the circuit when all loads are operational. Note that a good rule of thumb is that a full load should not be more than 80% of the rated capacity of a particular circuit.

Balanced distribution should be applied to ensure that loads are correctly grouped and distributed within each circuit of the entire electrical system. The good news is that original equipment manufacturers (OEMs) always specify power consumption ratings on their products. This provides a good reference so that electrical load balancing can be done properly.