4 tips on HVAC
1. Boiler Control Upgrades Plus Regular Maintenance Can Improve Energy Efficiency
Today's tip comes from James Piper, contributing editor for Building Operating Management and Maintenance Solutions magazines: Focus on boiler controls to reduce energy use.
New boiler controls can provide major gains in energy efficiency, performance, and safety at a much lower cost than replacing boilers. Older-generation boiler controls used mechanical linkages. With age and use, linkages wear and go out of adjustment, reducing the unit's efficiency. Older-generation controls also suffer from offset, which occurs when the system operates close to, but not exactly at, the desired setting.
Today's boiler controls incorporate microprocessors, solid-state sensors, and independent servo motors, which give managers accurate and reliable operation, eliminating problems such as offset.
When evaluating control options, it is important to remember boiler controls perform three basic functions: combustion control; water-level control; and flame safeguarding. If a facility uses multiple boilers, the control system must perform a fourth function: sequencing. Facility managers must factor all of these issues into their control decisions. Three types of boiler controls to consider upgrading are flue gas trim, sequencing and automatic blowdown.
Getting the proper controls installed is only the first step in achieving efficient and reliable boiler operation. To keep things operating that way over the life of the system, technicians must properly maintain controls. But the importance of proper maintenance goes far beyond efficiency and reliability issues. It also incorporates safe boiler operation.
Technicians must keep logs for boiler operations, recording operating parameters frequently enough to identify trends. Equally important, they must review those logs regularly to actually detect the trends.
At least once each month, technicians must test a boiler's safety equipment, such as the safety-relief valve, water-level control, and low-water fuel cutoff, according to the boiler manufacturer's recommendations. Larger boilers require more frequent testing.
They also should test all controls for proper operation and calibration at least once annually, and they should inspect, clean, and lubricate mechanical linkages according to manufacturer directions.
2. Replacing Rooftop Units Before They Fail Can Bring Significant Benefits
Today's tip comes from Building Operating Management: Look at the big picture to persuade top management it's worthwhile to replace rooftop HVAC units before they fail.
If your organization has made a practice of replacing rooftop HVAC units only when they fail, there are several arguments that you can use to try to persuade top management to replace them proactively instead.
The biggest consideration is the impact on business. Rooftop units often fail on the most extreme temperature days. Suppose one fails in the midst of a heat wave. Depending on the building, the indoor environment will be anywhere from unpleasant to unbearable.
How important is that? The extent of the impact will depend on the type of organization. An office building may be able to stay open and put up with grumbling from employees. But in a retail facility, customers can't be told to stay. And even with office space, if it's a leased building, the tenants aren't likely to forget the inconvenience.
Getting a replacement in as quickly as possible will be a top priority, of course. But that may mean having to accept a less than optimal replacement unit because it is the first one available.
When making the case to top management, remember to focus on business issues. Talk to department heads or other business leaders whose functions will be affected by failure of a rooftop unit. Find out if they can provide any estimates of cost to the organization. Talk to contractors about how long it would take them to install a new unit and what impacts a rush order might have on choices, then translate all of that into business terms such as higher first costs, overtime costs, or higher long term energy costs.
3. Optimize the Life Cycle of Motors and Drives
This is Chris Matt, Managing Editor of Print & E-Media with Maintenance Solutions magazine. Today's tip is specification strategies for motors.
The complexity of motor specifications might lead managers to unknowingly compromise energy efficiency by installing a replacement unit that is not designed for the job. For this reason, managers need complete information and critical spares before the need arises. This tactic will help managers avoid possible mistakes and expedite the installation. Also, ensuring the vendor maintains an inventory of critical motors and drives for quick delivery saves space in the facility's storeroom and reduces inventory costs.
Managers can optimize the life cycle of a motor or drive by following a few basic rules:
• Make sure the motor or drive is the right size for the application by having the component's nameplate information and involving the vendor in recommending solutions.
• Implement an inspection program that incorporates regular PM inspections, including visual, audible, and heat checks.
• Keep equipment and drives clean, dry, and tightly sealed.
• Establish a preventive or predictive program that includes cleaning and lubrication at regular intervals, oil analysis of gearboxes to check for wear particles, thermal imaging for electrical and mechanical hot spots, and vibration analysis.
By following these rules, managers will be able to identify problem equipment early. And if technicians perform indicated repair and replacement in a timely way during regularly scheduled shutdowns, then unscheduled downtime, maintenance time, and inventory costs will decrease, and energy efficiency will increase.
4. MSCA Star Certifies Non-Residential Mechanical Service Contractors
Today's tip from Building Operating Management: For facility managers looking to hire HVAC contractors, one certification program to check out is the MSCA Star certification.
The Mechanical Service Contractors of America created the MSCA Star designation in 2003 for mechanical service contractors that serve industrial, commercial and institutional facilities. Among the requirements for the MSCA Star designation:
• Contractors must have been involved in the heating, ventilating, air conditioning and refrigeration industry for at least five years.
• At least 25 percent of the contractor's service techs must hold the UA Star certification, an HVACR service technician certification from the United Association of the Plumbing, Pipefitting and Sprinklerfitting Industry of the United States and Canada.
• Employees have to attend at least one national or local program sponsored by MSCA or its parent group, the Mechanical Contractors Association of America each year.
• Inventory control programs for trucks and tools are required for contractors.
• Contractors must have documented service safety and health programs and must maintain what MSCA calls an "outstanding" safety record.
• All field personnel must be required to wear photo ID cards.
• Contractors must maintain a high-level of customer service. The MSCA Star qualification process checks contractor references with customers. To receive UA Star certification, technicians have to pass an exam designed to ensure that they are qualified to service, repair, maintain or retrofit a wide range of mechanical systems. Technicians also have to complete a 5 year apprentice training program and have work experience.
A third-party personnel certification agency, National ITC Corporation, administers the MSCA Star program, as well as the UA Star program and a wide variety of other industry certifications. NITC is certified under the ISO 9001 quality management standard and is ANSI-accredited.
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