While the economy takes its time turning around, each day I see more fire alarm system upgrades to replace obsolete equipment. On almost every project, I find the owner promoting a common thread. Simply put, he or she wants to know what can be done to fix the existing system with the least capital investment.

So you are caught between the owner’s price-conscious goal and ensuring the new system installation meets the requirements of the relevant building code as well as NFPA 72 2013, the National Fire Alarm and Signaling Code.

These upgrades range from a simple fire alarm control unit replacement to a complete system upgrade. Obviously, the latter seems to be easier, right? This is where the red flags appear and you should proceed cautiously.

A common mistake I see professional contractors make when upgrading a fire alarm system is planning a one-for-one replacement of all devices (smoke detectors, manual fire alarm boxes, etc.) and notification appliances (horns or speakers and strobes). Many contractors make this decision without thinking about whether the installed system they intend to replace met the code when it was originally installed or if it will meet the current one. When you provide a complete fire alarm system upgrade, you must meet the current edition of NFPA 72 enforced by the jurisdiction for the premises location.

Address the proper spacing of all detection devices, the proper mounting height of the manual fire alarm boxes and notification appliances. You should especially review the strobe placement, height and candela ratings for each strobe location. Additionally, recalculate the voltage drop to ensure the strobes and notification appliances will operate properly. For example, you may find that, even if you can replace strobes on a one-for-one basis, you may still need additional power supplies to operate the new units.

You also should take the extra time to investigate the wiring to ensure the installation meets the requirements of NFPA 70, the National Electrical Code (NEC). Never assume the existing fire alarm system works correctly or that the original wiring installation has no issues.

When upgrading the fire alarm control unit, ensure the powered devices and appliances are compatible with and will work properly when connected to the new control unit.

Before you agree to only change out the fire alarm control unit, verify that the smoke detectors on the system have not become obsolete. If you don’t, and one of the smoke detectors fails after you replace the control unit, the owner may find that all the smoke detectors must be replaced, and the owner will rightly feel you did not do your due diligence to review the system. Keep in mind that, although the owner told you to only replace the fire alarm control unit (often on the recommendation of the fire official), he or she still expects you to know your business well enough to advise what is really needed. The owner presumes that you have the proper expertise to offer thorough advice, so accept the responsibility to perform due diligence with every system you propose to upgrade.

When you plan to simply replace the fire alarm system control unit, consider if the existing system uses conventional technology or addressable technology, which will markedly affect the compatibility of devices and appliances with a new control unit. Sometimes, upgrading a conventional system to an addressable system has distinct advantages. If the owner plans to upgrade the system in phases, using an addressable control unit makes sense.

However, exercise caution in this scenario. You now have a control unit that will need programming, so consider all of the significant issues regarding addressable systems. For example, you will need to obtain the fire official’s approval to allow the new addressable points to have the same labels as the previous zones.

As with a full system upgrade, if you plan to reuse the existing wiring, determine if it meets the wire and cable specifications for the new fire alarm control unit. And again, ascertain that the installed wiring meets the NEC requirements.

When you attempt to meet the owner’s price goals, remember that, once you touch the system, you own it. Before assuming responsibility for the system, many professional contractors often require a complete system test to ensure it has no operational faults. If you intend to accept responsibility for the system, ensure you know what liabilities you will inherit. Protect your profits by exercising diligence in your review of any existing equipment you intend to replace.