News | United CoolAir

August 1, 2019 by Matt Hanson

R22 Refrigerant is Set to Expire Beginning in 2020

What to consider for the coming year

Blog HVAC Pic R22

As we approach 2020, R22 (Freon) will be set to expire or use in the USA. Many facilities with outdated equipment won’t be able to purchase R22 to replenish a leaky system. For many years R22 was the HVAC industry standard until manufacturers began switching over R410a. The R22 refrigerant has been phased out due to the negative effect it as on the ozone layer. The scientific community has known since the 1970’s that Freon has a negative impact on the planet. The US Environmental Protection Agency has set the date of January 1, 2020, for R22 to longer to be manufactured or imported in the US. This poses a problem for how this will impact your commercial HVAC system.

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July 3, 2019 by Matt Hanson

The Thermal Expansion Valve (TXV) Explained

What you need to know about refrigerant flow

The Thermal Expansion Valve (TXV) is an important piece of equipment in the HVAC industry. The valve is used to control the amount of refrigerant released to the evaporator section. In this way it controls the difference between superheat and the current refrigerant temperature at the evaporator outlet. Therefore, This in turn keeps its saturation temperature at the current evaporating pressure stable. The Thermal Expansion Valve function is the control the flow of refrigerant into the evaporator in response to the cooling load. Additionally, TXV’s measure the superheat at the outlet and react to this by increasing or decreasing the amount of refrigerant flowing into the evaporator to try and maintain a constant superheat.

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June 18, 2019 by Matt Hanson

Commercial vs Residential HVAC Units

Learn the similarities and differences between commercial and residential units

Commercial and Residential HVAC units share many similarities but contain many differences as well. While some HVAC manufacturing companies produce units for both markets, others specialize in one or the other. The biggest differences have to do with size, and also whether the unit is a packaged or split system. Commercial systems are typically modular in nature, which makes them more flexible and expandable. These units are for business applications and can serve very large office buildings to small shops.

Many times, HVAC units are installed while the building is under construction which presents a problem later on. Eventually the unit will be in need of replacement. Commercial units because of their size and complexity usually require more highly trained technicians to install and service the equipment. These types of HVAC units are designed to serve multiple zones and is capable of providing heating as well as cooling to the building. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) sets Minimum Ventilation Rates in Breathing Zone standards as to how much fresh air must be delivered for the number of occupants in a given room. HVAC units are based on tonnage or CFM (Cubic Feet per Minute). While ASHRAE advises 20 CFM per person in a health club, libraries only require 5 CFM per each individual.

The Common HVAC Installation

HVAC systems usually contain an outdoor condenser section along with an indoor evaporator section. In a residential installation, condenser sections are mostly located on the ground and duct connected. Alternatively, in commercial applications the condenser section is usually placed on rooftops while the evaporator section is placed indoors. Both commercial and residential outdoor units can be susceptible to weather damage and vandalism. Residential units are also usually much smaller than commercial units but cannot be expanded. If more cooling capacity is needed, the unit must be replaced with a new unit. Companies that install HVAC equipment usually include both commercial and residential installs. Installers have a product line card where they sell HVAC units from several different brands.

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May 24, 2019 by Matt Hanson

Sick Building Syndrome and what to do about it

Sick or tight building syndrome is a term that describes from the ill effects building occupants suffer due to poor indoor air quality. Although not attributed to any specific disease (SBS), leads to a loss of employee productivity.

An extensive list of symptoms related to (SBS) include:

headache
cough
dizziness
nausea
eye, nose or throat irritation
dry cough, dry or itching skin
difficulty in concentration
fatigue
sensitivity to odors
hoarseness of voice
allergies
cold, flu-like symptoms
increased incidence of asthma

shortness of breath on mild exertion
edema
palpitations
nosebleeds
cancers
pregnancy problems and miscarriages
Legionnaire’s disease
humidifier fever
pneumonia and occupational asthma
chest pain

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April 9, 2019 by Matt Hanson

Business Owners Guide to Commercial HVAC

When business owners are in need of a new or replacement HVAC system, there may be many questions that arise. First and probably most importantly is the cost. However, cost not only pertains to the price of the equipment, but to the installation cost as well. Equipment cost will vary from one brand to another and between companies performing the install. Since most buyers are usually not HVAC experts, they often defer to the expertise of the engineer or contractor and may not search or understand that there are alternatives.

When it comes to Commercial HVAC systems many can be quite large. Furthermore, in many cases they were installed when the building was under construction. Typically, an HVAC system consists of condenser section placed on the rooftop or outside the perimeter on the ground. While outdoors these units are susceptible to weather damage and vandalism. Next, the installation of an evaporator section takes place, usually inside a mechanical room where it cannot be easily relocated.

How Replacements can be Made Easier

Generally, HVAC units need to be replacement after just a few decades. However, replacing an existing unit can be a very involved process. Installers routinely tell building owners that replacing the unit would be a daunting task. To complete the retrofit installation, it is often recommended to remove some of the walls or part of the roof. The reason is although the old unit can be chopped up and removed, it is very difficult to get a replacement unit in the space. Additionally, a crane is often needed to hoist the replacement unit into place, especially if the height of the building is several stories.

The total cost of an installation is broken down into separate categories; labor materials, and tasks. Installation companies will compute hourly wage times how many laborers it will take to complete the change out. Other expenditures could include permits, insurance, supervision, warehouse, crane rental, and delivery.

The selection of the proper HVAC system is yet another consideration. Owners, architects, engineers, and contractors have the choice of chilled water, refrigerant direct expansion, packaged, air-cooled, water-cooled, and VRF systems. Will the system be a central or floor-by-floor method? Each of these will have pro and cons and can be one of the more difficult decisions to be made. Sometimes decisions are based on building codes. Historic districts usually have restrictions on placing units outdoors or on the rooftop.

There is a better way!

For retrofit installations, the design of United CoolAir (UCA) products helps avoid all of the unnecessary costs that can occur. This is due to United CoolAir’s design that involves a complete indoor installation. This factor alone saves the unit from weather damage and potential vandalism. Additionally, UCA units are built as modular units that fit through doorways, meaning there is never a need for expensive rigging or demolition of the building. UCA units can also fit into historic buildings, thus avoiding the aggravation of code restrictions. Additional permits or non-allowance for outdoor equipment. United CoolAir HVAC units not only save in installation cost but their units last longer over the competition.

February 27, 2019 by Matt Hanson

Choosing a Dedicated Outdoor Air System (DOAS)

In order to comply with current strict ventilation standards in the HVAC industry, manufacturers’ are introducing innovative new equipment to improve indoor air quality. Dedicated outdoor air systems (DOAS) are one such methods used to help regulate temperature and humidity. Schools, hospitals, offices, and other commercial spaces can all benefit from a DOAS unit. As these systems become more popular throughout the USA and Canada, technicians and end users need to understand the operation and importance of these units.

Although DOAS units are not the primary source of cooling, they help the main HVAC unit work more efficiently. These units function by bringing in fresh air independently of other cooling and heating equipment. This pretreated air will ultimately save fan energy on the main HVAC unit and improve the overall indoor air quality. These units can be air-cooled, water-cooled and chilled water and may include variable capacity compressors.

How to Get Started

Specifying a DOAS unit usually begins with selection software. This takes the basic parameters of the installation and focuses on the specific needs and requirements for fresh air. The software will calculate the performance expectations and recommend additional modifications to the basic package. A variety of fresh air units handle a range of CFM and tonnage and include options such as water-source heat pumps and modulating hot gas reheat.

Other fresh air units could include direct expansion with an energy recovery enthalpy wheel. The unit should be able to handle the large latent ventilation load and deliver “neutral” air of 72°F to 75°F @ 50% RH. By separating the sensible load from the latent load, the unit will remove moisture from the primary source of fresh outside air. What this does is reduce the load on the primary AC unit that will be used in cooling the space. Ultimately, this leads to greater efficiency and better indoor air quality with a lower overall cost.

Why Install Equipment Indoor?

Many HVAC manufacturers provide outdoor rooftop equipment as DOAS units, but occasionally a customer might require an all indoor packaged unit. This is the case when the building topography does not allow for outside mounting. Furthermore, codes that affect historic buildings often don’t allow for HVAC equipment to be installed outdoors. This is the case even if there were ample room on the roof or outside. The indoor packaged solution typically realizes a smaller footprint. This aides in new installations as well as for retrofitting as part of a VRF or conventional DX air conditioning project.

Ideally, the performance of your DOAS unit should meet or surpass the ASHRAE 90.1 standards of ISMRE 11.1 and ISCOP 8.0 and adhere to a sound rating of less than NC-40. Dedicated Outdoor Units also include options such as the installation of MERV 8 or 13 filters. Units can also include special coil coatings to prevent rust and corrosion when installed in harsh conditions. Some examples would include Marine or paper mill applications. Lastly, units may also include a manual on/off override switch and meet the power requirements of 208/230 single or three phase or 460/3 phase power.

When calculating the need for a DOAS unit it is important to understand all the benefits.

By removing outdoor contaminants before they enter the building the indoor air quality will be greatly improved. Additionally, this will allow the main cooling unit to run more efficiently.
The dehumidification process removes moisture from the entering air which helps prevent the formation of mold. These elements can negatively affect the health of the building occupants.
Energy savings are also achieved by separating the ventilation requirement from the main cooling or heating unit.

Dedicated Outdoor Air Systems have become an integral component to an overall approach to HVAC installation. As concerns about climate change drive governments to enact more stringent energy requirements in the manufacturing process; DOAS units will continue to grow in importance. Ongoing developments will ensure that these types of units will become even more efficient and used well into the future.