Reading an article recently about a school that faced a mandatory shutdown as a result of a boiler malfunction, it occurred to us that the reporter may have been fed inaccurate information, or misunderstood the information presented. Though, it could simply have been too early in the investigation to know exactly what caused gas to ignite, resulting in a very audible explosion, which knocked out roof exhaust fans and damaged multiple boiler units. The school was forced to close until temporary replacements could be installed and approved.
Worse than the damage done is what could have happened during such an explosion. The school was fortunate that no one was injured as a result of the malfunction. Fortunately, no injuries were reported and students were able to enjoy a couples of days off.
Based on the facts presented, the problem likely could have been a result of an improperly operating gas ignition system. If the installed safeties were not operating as they should have been, it could have caused the dangerous malfunction.
In most cases, larger commercial boilers, piped in series, like the ones described in the article, do have a mechanical flue gas system that operates in conjunction with the boilers. The exhaust system must match a predefined pressure set point before the system will allow the gas and ignition to operate.If the set point is not met than the ignition system and gas system will not operate.
In order to prevent problems like this in the future, the school could install a No Shok621/622 Series Explosion Proof Pressure Transmitter. This would take the place of what was very likely a faulty (or bypassed) safety device, already installed. Used in conjunction with the boiler control module, the No Shok device would prevent the gas and ignition system from operating until proper pressure conditions were detected.