Lately we have been involved with "mission critical" projects which take the word redundancy and introduces a whole new meaning for backup of building systems. Over the years, design engineers have incorporated standby equipment on a regular basis. Now we are seeing "N plus N," where every piece of equipment has a matching piece of equipment.

If design-builders were to research the various strategies facility managers apply when it comes to exercising and/or using this standby equipment, they may be surprised at the feedback they get from operators. Redundancy doesn't come without a price.

Redundancy Can Get Expensive

When determining the first cost associated with installing a standby pump, you can figure on a furnished and installed budget of $5,000 to $7,500 for this piece of equipment that will also take up space in an equipment room. If the design engineer duplicates this concept with the heating system by adding a standby heating pump, the premium increases to $10,000 to $15,000 plus the space required for these pumps in the equipment room.

Figure in the limited number of "run-hours" for this equipment and you may begin to question the merits of a standby pump vs. investing in a really good, reliable service company who could quote you a four-hour response time and a "standby fix-it" price should a pump fail. Investing in a service company may be a better investment than taking up floor space with one or two extra pumps. The bottom line to this thought is that the design-builder and the customer shouldn't automatically buy redundancy. Extra pumps and the changeover strategy is not always easy or energy efficient. Instead, consider investing in a proactive service company.

No Guarantees

Getting back to mission-critical space, redundancy doesn't automatically ensure there won't be a failure/interruption. Recently I was reading an article on the benefits of redundancy that was overlaid with building automation. The writer of the article highlighted the complexity of the system, the automatic switchover of equipment, and if all else fails, he noted that the operator could take manual control of this very complex system.

That last option is the first concern I would have with this theory. Riding a bike doesn't qualify one to drive a motorcycle. If this mission critical hvac system is so sophisticated and automated that a highly qualified person need not apply, then the customer may not feel compelled to invest in the right people to operate the building systems 24 hours a day, 7 days a week. The key word here is "people." A customer with a complex installation needs to invest in several people and not just one person.

Another concern a customer should have is finding the right people who are highly qualified to operate and maintain these critical systems. In many parts of the country, there are lots of qualified people for the job. In less populated areas, this may be a problem. When this is the situation, redundancy doesn't guarantee 24-7 without a "blip."

Outsourcing Control Of The Building

There are a couple of solutions to this problem of making redundancy a seamless process. The first option may be to contract out the operation and maintenance of the building systems. Finding a highly qualified service company may be easier than finding enough equally qualified employees. When the construction cost for mission critical facilities are running at about $400/sq ft, investing in $1/sq ft for service annually can be considered a real bargain. A combination of onsite building employees and a highly qualified service company to support the facility may be another alternative for reliable redundancy.

It is not unusual that design engineers focus on what they know best, design engineering. Unfortunately great system concepts still have to operate efficiently, reliably, and for the maximum useful life of the equipment. With mission critical systems, redundancy and the need to increase this redundancy can provide a false security without an operation and maintenance plan. ES