#hvacsystem Archives - United CoolAir

May 4, 2022 by Matt Hanson

BTUs in Air Conditioning

When it comes to air conditioning, calculating BTUs is an essential part of determining the size of the unit. A BTU or British Thermal Unit is the measure of heat energy that comes from a thermal unit and an Imperial Gallon is 10 pounds in weight. Therefore, a BTU is 1/10 of an Imperial Gallon or one pound of water at sea level and a BTU will raise water temperature one degree Fahrenheit. However, in air-conditioning, we are not changing water temperature, but the temperature of the air. While the metric system has taken over most industries, BTUs in air conditioning remains the standard due to their significance in heating and cooling.

What does a BTU do?

Simply put, a BTU measurement shows how much energy an AC unit uses to remove heat from a space within an hour. This allows HVAC techs to determine what size HVAC units should be installed. When an HVAC tech determines BTU usage, they must account for many factors. Every BTU has a corresponding tonnage, which has nothing to do with weight but is in reference to a unit’s cooling capacity.

A ton of cooling known as refrigeration is the amount of heat it takes to melt a pound of ice in a 24-hour period. Furthermore, 12,000 BTUs is equal to one ton of cooling and there are guidelines for how many BTUs are needed for the square footage of a space. Also, heat in air conditioning is referring to energy and not temperature. Air conditioning systems simply move energy from one place to another.

Square Fee	BTUs
100-150	5,000
150-250	6,000
250-300	7,000
300-350	8,000
350-400	9,000
400-450	10,000
450-500	12,000
500-700	14,000
700-1,000	18,000
1,000-1,200	21,000
1,200-1,400	23,000
1,400-1,500	24,000
1,500-2,000	30,000
2,000-2,500	34,000

Here is a resource to quickly calculate the BTUs needed.

Calculator

Conclusion

Many factors go into choosing an HVAC system and BTUs are just one factor in this calculation. It also helps in determining kilowatts which has a direct impact on energy costs. Equally important are room size, aspects of insulation, humidity levels, ceiling height, window size, and room occupancy. Being informed of all these factors make sure the perfect sized HVAC unit is installed to serve the cooling needs.

December 29, 2021 by Matt Hanson

Improving Indoor air hygiene

Since the onset of the novel corona virus that has become a pandemic, there is emphasis placed on improving indoor hygiene. People across the globe now realize that prevention of illness needs to be part of the strategy to control infection. Although mask wearing and social distancing may reduce transmission it is not enough to solve the problem.

Keeping building occupants healthy begins with making sure we are combating indoor air pollution. The Environmental Protection Agency (EPA) recommends fresh air standards for commercial buildings. Probably due to the fact the average American spends up to 90% of their time indoors and the workplace is one such instance.

To ensure fresh air is at satisfactory levels the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62.1 has established guidelines. These guidelines give building or facility managers a baseline for acceptable Indoor Air Quality and ventilation.

Identifying pollutants

Besides Corona there are other airborne pathogens that contribute to poor health. Indoor pollutant includes microorganisms, germs, spores, molds along with carbon dioxide and carbon monoxide. Since many pollutants have no smell and cannot visibility they can be potentially dangerous.

Combined together these variables come together to make indoor space unhealthy hence the term sick building syndrome. During the Summer of 1976 a new ailment named Legionaries disease during a convention of the American Legion in Philadelphia, PA. This was due to a strain of bacteria called Legionella found in the cooling tower of the AC system.

Symptoms of poor Indoor air

When buildings contain too much humidity people will describe them as being muggy. Then symptoms such as congestion, dizziness, fatigue, nausea along with irritation of the eyes nose and throat can set in. However, many of these problems can be identical to a cold or allergic reaction. Only a medical professional can diagnose the true source of these symptoms.

Solutions for Improving Indoor air

While providing us cooling and heating our air conditioning units can be made to be healthier. Fortunately, we have many ways in which to diminish poor indoor air quality and actually improve the air we breathe. The first way to improve indoor air is with a Dedicated Outdoor Air System (DOAS) to continually bring in fresh air and circulate it in spaces.

Fortunately, we have many ways in which to diminish poor indoor air quality and actually improve the air we breathe. The first way to improve indoor air is with a Dedicated Outdoor Air System (DOAS) to continually bring in fresh air and circulate it in spaces. A DOAS system will remove humidity from the room and help the AC unit operate more efficiently. Additionally, filtration and air sanitization are helping to make buildings safer for occupants.

January 6, 2020 by Kevin Stepp

Recovering Energy from Class 2 Exhaust Air

The Problem

Providing a healthy environment must be the top priority for any air conditioning design. This can be difficult though, especially in spaces that generate less-than-ideal breathing conditions. Nail salons, health clubs, and bathrooms are just a few examples of spaces where processes or people taint the air with undesirable chemicals or odors. In these spaces, building designers are missing an opportunity to save valuable energy while providing healthy buildings.

ASHRAE 62.1 – 2019 designates air in these spaces as Class 2 air and stipulates that it must be exhausted. Fresh, but expensive to treat, outside air must be brought into the building to replace the exhaust. Here, designers are dropping the ball if they simply throw away the exhaust air. It contains valuable heat energy that should be recovered and used to reduce the energy needed to condition outside air.

The Solution

United CoolAir’s Alpha Aire utilizes two energy recovery devices to extract heat energy from the exhaust and pre-cool (in summer) and pre-heat (in winter) outside air before it reaches a coil. The unit design reduces the load on the cooling and heating coils to as little as 1/3rd that of a standard outside air unit. At a fraction of the operating cost, Alpha Aire delivers room-neutral (roughly 73° and 50% RH), fresh air to a building.

One common concern with Class 2 applications is whether the exhaust air will be transferred back into the building by way of the energy recovery wheel. United CoolAir utilizes a molecular sieve enthalpy wheel with a rated EATR of 0.5% or less. This means that less than one half of one percent of air leaving the building will be trapped in the wheel and recirculated into the space, a rate undetectable to humans and one far lower than the 10% allowed by ASHRAE 62.1 – 2019.
Designers should not hesitate to use all of the energy at their disposal. Alpha Aire gives them the opportunity to do just that. Call or click the link above to find out more.

Applications

Toilet rooms	Nail salons	Museums
Locker rooms	Pet shops	Hotels
Shower rooms	Barber shops	Health clubs
Science labs	Restaurants	Laundry rooms
Libraries	Bars	Pharmacies
Art classrooms	Bowling alleys	Churches

October 25, 2019 by Matt Hanson

Industrial Grow Room Units

As cannabis becomes legalized or decriminalized throughout the United States, Grow Room units are in high demand. Medical applications of the plant alone have led to further community acceptance and therefore more facilities have emerged for growth and distribution. In order for this up-and-coming industry to thrive, HVAC companies have developed specialized equipment that promotes indoor plant growth.

Growing cannabis indoors on a massive scale is an elaborate process. To start with, optimal growth conditions require stable temperatures both day and night. When the plants are in the early stages of development they need oxygen-rich air for vigorous growth. Grow room unit development leads to the control of both temperature and humidity in the various stages of plant growth. In particular, the heat stress on developing plants can quickly ruin a crop.

The two-stage humidity problem

When the humidity levels rise too high, conditions become such that mold can develop. Likewise, when levels of humidity fall too low this can add additional stress to the plants. The cannabis plants thrive best when relative humidity is kept within a manageable range.

Grow Room Units by United CoolAir

When it comes to Dedicated Indoor Agricultural System (DIAS) AKA, Grow Room units, United CoolAir is on the cutting edge. Starting in the Spring of 2018 we began producing equipment for Cultiva Systems. This is a complete system unlike the conventional approach that utilizes a standard air conditioner to control temperature and a separate dehumidifier to control humidity. The DIAS has the required capacity for late flower loads and enough turn down to maintain conditions during the earliest stages of the plant. Powerful moisture removal capability and full condensing modulating hot gas reheat keep the room conditions on target. Integral controls and advanced components maximize energy efficiency while achieving the desired conditions; therefore, lowering the operating cost to the grower. Furthermore, these units range from 10 – 45 tons and come in both horizontal and vertical configurations.

September 13, 2019 by Matt Hanson

All about packaged units in air conditioning

Since the invention of the air conditioner in 1902, engineers have developed various ways of handling the HVAC process. The evaporator and condenser sections are the two major components of Heating, Ventilation and Air Conditioning (HVAC). This is the case as it applies to Direct Expansion (DX) type systems. At the same time, the indoor air absorbs heat inside the evaporator section. The condenser converts the vapor to a liquid by cooling it down. This section is usually located outside on the roof or on the ground. Because the two sections are located in different areas we call this a split system.

A packaged unit is when the heating and cooling components are contained in the same unit. This type of system can be beneficial when space is minimal. Many times, the placement of this type of HVAC is located outdoors but can also be installed completely indoors. Connected to both the supply and return air ducts; these operate similar to a central air system. The delivery of these packaged units can occur as both air-cooled or water-cooled systems.

The Refrigeration Cycle

In the refrigerant cycle, air-cooled or water-cooled liquid travels through an expansion valve where it converts to a vapor. The vapor then absorbs heat inside the evaporator before moving on to the compressor. After the compressor, the vapor then goes to the condenser where the refrigerant is air or water-cooled. The application of a heat exchanger component is installed with shell and tube; plate and frame, or coil.

The cooling effect is achievable by means of a continuous supply of water added to the system. Sometimes building codes do not permit an HVAC system to be installed outside. In this case, packaged units are installed as a solution. United CoolAir produces these all-indoor packaged systems. By the way, the self-contained HVAC units and are available with multiple air path configurations.