What Are HVAC Rooftop Units, And How Do They Work?

Roof top units, or RTUs, are a common fixture of commercial buildings. Nearly half of all commercial buildings across the nation take advantage of RTU technology, including office buildings, manufacturing facilities, hospitals, retail venues, and schools. Providing heating, cooling, and ventilation, RTUs have been servicing the comfort needs of large buildings since the early days of electro-mechanical air conditioning in the early 1900s.

Why Rooftop HVAC Systems?During the early 20th century when these systems were introduced, most large businesses were located in crowded urban areas, where no room existed between buildings for the large outdoor units necessary to provide adequate cooling. To get around this issue, manufacturers designed systems that could access ventilation and operate from the roof.

Plentiful Benefits
Newer, albeit more efficient versions of RTUs are still in use today, remaining at the top of building where they take up less space, require less maintenance in the form of weed, grass and debris removal, and keep the grounds more attractive. This location also makes the systems less prone to theft and tampering, and allows for easier commercial HVAC maintenance without interfering with daily work routines. Because there are few space and design concerns with RTUs, expanding the heating, cooling, and ventilation capacity of these systems is also much easier due to their out-of-sight, limited use locale.

How Do Rooftop HVAC Systems Work?Far more flexible in design today than they were just a generation prior, RTUs work a little differently than the standard home HVAC system. When cooling is necessary, RTUs draw warm air from within the building, cooling it with the help of a cooling coil, and redistribute it to the space below. When the outside air is cooler than the air inside, however, RTUs have the capability to save energy, taking advantage of outdoor conditions with the help of a specialized control system called an economizer. The economizer system opens up an air damper when outdoor air is cooler, reducing the need for the system to cool indoor air mechanically, and taking a 15-80% bite out of energy use depending on outside climate conditions. In addition, if a building requires added ventilation, outside air is always available. When paired with an occupancy or CO2 sensor, the system can bring in necessary fresh air on demand, responding to ventilation changes on an as-needed basis.

How Efficient are Rooftop Units?
While older RTUs are notoriously inefficient, newer RTU tech and retrofits offer far more reliable and efficient operation. With heating and cooling accounting for over 25% of the average commercial building’s energy use, such improvements in efficiency have a lot to offer in helping businesses cut energy costs, reduce their carbon footprint, and meet regulatory standards, not to mention in boosting productivity and protecting workers against temperature extremes.

Looking for opportunities to improve the efficiency of your rooftop unit? Contact the experts at H&H Commercial Services to schedule a system evaluation and learn more about opportunities for savings today.

This post originally appeared on: https://hhcommercialonline.com/hvac-rooftop-units-work/

What are Water Cooled Chiller Systems

An alternative to air-cooled systems and rooftop units, water cooled chiller systems are typically used for industrial and commercial applications for their significant energy savings benefits, and to aid companies in their attempts in reducing carbon emissions.

How Do They Differ From Air-Cooled Systems?

Though water and air cooled systems share many components in common – evaporator, condenser, compressor, expansion valve - unlike air-cooled systems, which disperse heat via an air-cooled condenser coil, water cooled chiller systems use water to absorb heat, dispersing it into the air through a cooling tower. It is this component that gives water cooled systems an efficiency advantage over air-cooled and rooftop systems, from 10-100% depending on the setup.

Why Are They So Much More Efficient?

Water is more energy dense than air, providing more efficient cooling than traditional air-cooled options. However these systems come with one main drawback: A higher equipment cost. They are typically used in locations larger than 200,000 square feet, where cooling needs will quickly offset the added cost of equipment. Other applications include industrial use, such as the cooling of plastics and metals, and the cooling of small and large multi-storied structures like universities, hospitals, and large office buildings, as the systems don’t require ducts to push air through multiple stories. With system sizes ranging from 20 tons to several thousand, applications are wide and varied.

Choosing a Water cooled System

Operation and function of water cooled systems will vary based on your choice of system type. Chillers are typically chosen by application and cooling capacity required in relation to the trade-off between initial investment and operating costs. Make sure to consult with a Commercial HVAC Mechanical Contractor before deciding on the System. Styles include:

Centrifugal Compressors

The most efficient of water cooled system choices, this system type includes magnetic-bearing compressors, which generate less noise and vibration than other styles and offer significantly improved part-load efficiencies in certain applications compared to screw and scroll style compressors. Centrifugal compressors are typically used in applications requiring 300 tons or more of cooling capacity, though some newer models offer variable-frequency operation.

Screw Compressors

Dominating the upper end of the capacity range, screw-style compressors are typically used for applications requiring less than 300 tons of cooling capacity.

Scroll Compressors

Scroll compressor are common in applications requiring less than 300 tons of cooling capacity.

A Difficult Decision

Due to the complexities of each application, in-depth analysis is essential to maximize efficiency opportunities with water cooled chiller systems. Various equipment options, load factors, and operating strategies must be considered by professionals in-the-know to ensure a solid investment and lasting performance, such as chiller efficiency, the efficiency of pumps and fans, full/partial load operation, variable frequency versus constant speed compressors, interaction between components, and operating techniques.

Considering an upgrade or experiencing issues with your existing water cooled system? The professionals at H&H Commercial have skills beyond the typical residential or business installation. Contact us to learn more about our trusted commercial services today.

This post originally appeared on https://hhcommercialonline.com/water-cooled-chiller-systems/

How Does An Industrial Chiller System Work?

Upgrading the air-conditioning unit in your commercial building to an Industrial Chiller system is an excellent way to both make your building more green while reducing your energy expenses. Chillers work extremely efficiently in creating a comfortable environment for employees and visitors, as well as doing a good job cooling products, computer systems or machinery as well.  

What are Industrial Chillers?

Water cooled chillers and air cooled chillers are two types of refrigeration systems that can both cool and dehumidify air in industrial or commercial buildings. Vapor-Compression Chillers are a third technology. Chilled water can be used both for space cooling and also for processing. Chillers can use a variety of types of compression systems and fluids but have the same four basic components:

• Evaporator
• Condenser
• Compressor
• Expansion Valve

How an Industrial Chiller System Works

Each type of chiller works using a similar cycle:

1. Liquid refrigerant starts in the evaporator and goes over an evaporator tube, absorbing the heat and evaporating into a gas.
2. The compressor draws the gas out of the evaporator and moves it into the condenser which raises the temperature and pressure.
3. The condenser tubes absorb the heat in the vapor.
4. Then the pressurized liquid refrigerant goes through the expansion valve which causes the temperature and pressure to reduce.
5. Finally, the liquid refrigerant again flows across the chilled evaporator tube, beginning the cycle again.

Which Chiller is Best?

No one chiller is best in all situations. Each building is unique and to determine the best type of industrial chiller for your particular building, you need to consult a company which has extensive experience in a variety of different types of buildings. They can determine what your needs are and which sort of chiller would meet those needs most effectively.

Industrial Chiller Maintenance

In order to function efficiently, chillers need to have expert inspection and maintenance by an experienced chiller repair contractor. Basic checks include:

• Inspecting the chiller for refrigerant leaks.
• Making sure compressor pressures are in the correct range.
• Checking motors, starters, relays, and contactors.
• Examining unloader operations and hot gas.
• Using superheat and subcooling temperature readings and discharge line readings to check for maximum efficiency.

H&H Commercial Services, Inc. is Your Best Choice for Chiller Services

With well over 30 years of experience in providing top quality industrial chiller systems in the Philadelphia City area, H&H can handle your chiller needs, no matter how complicated. If you are considering replacing your current system, our HVAC system experts are trained to assess your needs and customize a solution which takes into account your budget and your particular industrial cooling situation. Furthermore, if you need repair of your current chiller system, H&H repair services have the expertise to tackle any repair job and the connections to top manufacturers to make sure we get the parts quickly so that your job is done in a timely manner.


This post originally appeared on: https://hhcommercialonline.com/industrial-chiller-system-work/

Why You Should Not Hire A Residential HVAC Contractor For Your Commercial Building

Keeping your building at a comfortable temperature is important for your business to run efficiently. When something goes wrong, or you need to consider a new installation, you might be tempted to hire a residential HVAC contractor. However, there are many significant differences between residential and commercial systems. In truth, hiring a commercial HVAC contractor is a better choice for repair, maintenance, and installation of a new system. Here is why you should not hire a residential HVAC contractor for your commercial building:

Commercial HVAC Contractors Are Certified Technicians
Because of the complexity of commercial HVAC systems, major manufacturers have training and certification programs to make sure that technicians understand how to install and repair them correctly. Residential HVAC contractors generally don't have these certifications, which means they may not:

• Have the training to understand how to correctly install or repair systems.
• Be able to balance the temperature needs of different areas of your building such as a computer room.
• Have easy access to parts for servicing.
• Be able to offer you the best warranty.
• Offer regularly scheduled inspections and maintenance that can extend your equipment life and make sure it continues to perform at maximum efficiency year round.

Commercial HVAC Contractors Understand Business Building Needs
With larger spaces, more people and specialized room needs, commercial buildings require different equipment and more complicated systems analysis than residential properties. Not only does your building need heating and cooling, it also needs dehumidifying. Moreover, special areas like computer rooms or natatoriums require unique HVAC solutions and equipment. Commercial HVAC mechanical contractors have:

• Expertise in analyzing room sizing.
• Understanding of effective design and engineering of commercial HVAC systems.
• Access to a variety of types of products for unique situations.
• Experience in quality installation and adjustment of systems.

Commercial HVAC Contractors Can Save You MoneyRunning your HVAC system is a significant expense for your business. While a residential contractor might be able to keep your system running, they probably don't have the experience to help you optimize efficiency and reduce energy use.H&H mechanical repair services have the knowledge to make sure your system:

• Runs at the highest level of efficiency so that you save money on electrical bills.
• Is not overburdened so that it lasts as long as possible and doesn't require extra repairs.
• Maintains your building temperature at a safe level for your computers and equipment.
• Keeps your employees, clients, and guests comfortable in an energy efficient way.

H&H Commercial HVAC Mechanical Contractors Offer Superior Services
With over three decades of experience, you can trust H&H Commercial Services to do the best job in helping you choose the best system for your building and to keep it running as efficiently and effectively as possible. Our technicians are factory trained in all of the major brands of commercial equipment, including:

• Dunham-Bush
• Semco
• The Whalen Company
• Desert Aire

With our expert technical support and troubleshooting assistance, you can be assured we will quickly diagnose and service any problems you encounter. Most importantly, our commitment to customer service, integrity and honesty mean that you will get fast and efficient service on your commercial property, whether large or small.