Dadanco Blog

New Rep for Southern California!

Mon, 23 Apr 2018 16:21:00 GMT

Dadanco has chosen Zaretsky Engineering Solutions (ZES) as their new distributor for Southern California. They will start carrying the Dadanco line effective May 14^th, 2018.

“We are excited to add Zaretsky Engineering Solutions to our family of distributors. They will make a great addition, as ZES is a specialty engineering and sales organization,” said Cassidy Bowman, Operations Manager, Dadanco Inc. “The customers in ZES’s region can now get the best chilled beam and induction products available. We look forward to bringing the unequaled benefits of Dadanco products across ZES’s region.”

“ZES has always participated in the state-of-the-art projects where chilled beams are applied,” added Andrew Beggs, COO of ZES, ”Having Dadanco products to offer alongside our other premier products such as Aircuity, Phoenix Controls, and Cylon-Automatrix means we be will be of even greater value to sophisticated design engineers, building owners and contractors.”

Zaretsky Engineering Solutions began in 2012 by Roman Zaretsky, a respected mechanical engineer with vast experience in HVAC solutions. The Fountain Valley-based company’s focus and goal from the start was to provide the highest quality of technical expertise and support, as well as exceptional customer satisfaction and service. Phoenix Controls was the first product line that ZES distributed, but soon after ZES added a full suite of critical space solutions including Aircuity and MK Plastic. ZES also provides BMS integration services with their Cylon-Automatrix controls products, as well as other HVAC products.

Dadanco, a leading manufacturer in today’s modern HVAC industry, was founded on innovation. Born in Australia, the initial breakthrough centered around a new nozzle design that allowed perimeter induction systems to operate more quietly and efficiently than ever before. Later, as popularity for Dadanco advancements grew in North America, more solutions followed to answer specific concerns resulting from rapidly rising energy costs as well as stricter environmental standards. Continually adapting to the evolving needs of specific customers remains an accepted challenge to our technology team and the source of our continuing development.

Contact: Andrew Beggs, Chief Operating Officer

Zaretsky Engineering Solutions

714-640-3530

abeggs@zaretskyengineering.com

www.zaretskyengineeringsolutions.com

Condensing vs Non-Condensing Chilled Beams

Wed, 31 Jan 2018 14:37:43 GMT

Condensing vs non-condensing chilled beams.

Active Chilled Beam (ACB) systems were first introduced as an alternative to radiant cooling systems that allowed for greater cooling capacities and lower capital costs. The two systems have many design philosophies in common, including humidity control strategies.

Early ACB applications, and the majority of recent ones, have utilized the same basic approach to humidity control as radiant systems. All latent cooling (space and ventilation) is done centrally at one or several air handling units. These AHUs are sized such that they have sufficient latent capacity to keep all zones they serve at or below a design absolute humidity level at all times. Dehumidification is 100% handled by the primary air delivered to the chilled beams, and the chilled water coils in the ACB units are used to do sensible cooling (temperature control) only.

As in radiant cooling systems, the chilled water delivered to the ACB units is maintained at a temperature slightly above the dew point temperature of the spaces they are in, which typically works out to be 56 - 58°F. This ensures that condensation never forms on the coils of the ACB units. Due to the insulating of the air film on the coil fins the apparent dew point is 2-3F lower, thus 52 – 53F in a typical zone.

Recently, some ACB systems have been designed with a very different approach to humidity management. Rather than keeping coils dry, these systems are designed to do latent cooling with the ACB unit cooling coils. With this strategy, the ACB system has much more in common with a fan coil unit (FCU) system than a radiant cooling system. This design approach (Condensing ACB systems) has some advantages to traditional non-condensing ACB systems, but also has a number of drawbacks.

As the name suggests, condensing chilled beams accumulate moisture during their normal operating conditions. As a result, these systems and the beams themselves must be designed with condensate removal in mind. The units require vertical coils and drain pans, and the systems need drainage lines and potentially condensate pumps. Condensate lines & pumps increase first costs, and the type of ACBs do as well. ACB models suitable for condensing operation are usually much more expensive than basic ACB models without drain pans. These costs are typically offset by other savings. Condensing designs only require one chilled water temperature, so there is no need for a heat exchanger, dedicated chiller, or mixing valve & associated controls. AHUs can be less expensive because they do not need to do nearly as much dehumidification, and they may require less airflow in sensible load driven applications. The number & size of ACB units can be reduced since lower water temperatures allows the beams to have more cooling capacity, but this is often not the case because the beams have to do a lot of extra (latent) cooling that is done at the AHU in non-condensing systems. This allows the AHU to be sized for only the outdoor air requirement needed, in certain cases.

Non-condensing ACBs are a very low maintenance, long lifecycle system. When run dry, ACB coils need only to be vacuumed occasionally, the frequency depending on the building. In low-lint environments such as most offices, it is common to require cleaning only once every several years. In spaces such as hospital patient rooms, vacuuming may be required every several months due to lint accumulation that can occur. No filters are required, and more intensive coil cleaning is never needed. In condensing ACB systems, significantly more maintenance is required. Condensation on the coils causes dust and dirt to get stuck to them, so a lot of the debris cannot just be vacuumed or dusted off. Most of this can be avoided by using a filter on the coils. Dust and other particles will be captured before depositing on the fins, which cuts down on required coil cleaning but is a significant maintenance cost in itself, since typical projects contain hundreds of ACB units which will each need at least one filter replaced every few months. Coils are not the only maintenance issue, the drain pans and drainage lines will need to be periodically checked for blockage and cleaned. If condensate pumps are used, they too will need to be maintained. Lower water temperatures also mean that more chilled water pipe insulation is required, and there is a much greater chance of having insulation get wet from condensation and failing over time. There is also the issue of moisture or standing water in the drain pans and lines that can lead to mold and other health concerns.

Filters also impose a significant penalty to induction rates and therefore cooling capacity of the beams. Brand new filters cause large performance decreases, and that only increases as filters get dirty. There is also a loss of efficiency due to water droplets collecting on the coil and blocking much of the free area needed for airflow, between both of these effects, much of the increased capacity gained from lower temperature water is lost.

Use of lower temperature water also means that condensing ACB systems will have much fewer water-side economizer hours in most climates, and they cannot take advantage of the higher chiller efficiencies that come with generating higher chilled water temperatures. Other green technologies can be used in conjunction with these higher temperatures including high efficient cooling towers, geothermal loops, district CHW loop and energy saving heat pumps.

Yang, Li; Braun, James E.; and Groll, Eckhard A/, "Te Impact of Fouling on the Performance of Filter-Evaporator Combinations"

(2004).International Refigeration and Air Conditioning Conference.Paper 630.

htp://docs.lib.purdue.edu/iracc/630

Chilled Ceilings in Parallel with Dedicated Outdoor Air Systems: Addressing the Concerns of Condensation, Capacity, and Cost -Stanley A. Mumma, Ph.D., P.E.

VRF REJECTED!

Wed, 03 Jan 2018 17:58:00 GMT

VRF Rejected by the US Military? DoD has placed special requirements on these systems due to their inherent risks.

Three primary risk areas have been identified:

1) VRF systems currently contain proprietary hardware and software in conflict with 10 USC 2867,

2) VRF systems increase the risk of adverse mission impacts due to new EPA leak-rate rules on HFC refrigerant systems (if 50 lbs or greater of refrigerant) and the challenge of locating and repairing a leak in often hard to access areas

3) VRF systems have uncertain lifecycle costs (LCC) making comparisons with traditional HVAC systems difficult.

Benefits of using a 6-Way Valve

Wed, 20 Dec 2017 19:16:31 GMT

In the past, active chilled beams needing to perform both cooling and heating in a space were installed in a 4-pipe system. This meant that, due to the construction of the chilled beam coil, approximately 75% of the tubes used will be circuited for cooling only and the remaining 25% of the tubes will be circuited for heating only. By creating these two circuits the coil is unable to produce the same capacity as a coil using all of the tubes for heating or cooling. To combat this, a 6-way valve can be used allowing all of the tubes in the coil to be used for heating and cooling. This allows for the flexibility of a true 4-pipe system with the performance of a 2-pipe system, at a lower first cost than a 4-pipe system.

A 6-way valve is essentially two three way valves in a single valve body with a common actuator that controls the water is being delivered to the beams. Supply and return pipes from the chilled and hot water systems are connected to four of the six ports on the valve while the other two ports are for the supply and return to a zone of beams. During the summer the valve is signaled by the Building Automation System (BAS) to open the chilled water sequence. When the season changes to winter the valve is signaled to flip shutting off the chilled water sequence and opening the hot water sequence. The valves change over between hot and chilled water and modulate flow rates to control temperature, rather than using mixing for control. However, because of the common zone piping, water in the two loops does mix together over time, so both loops must have the same chemical treatments, such as glycol percentages.

As mentioned earlier, by using a 6-way valve the chilled beam is now able to utilize all of the tubes of its coil and produce a higher capacity. This opens up the potential to use less primary air, less secondary water, and even less or smaller beams. The valve also saves money on the cost of installation. Since two pipes are used to supply water to a zone of beams the extra pipes from the 4-pipe system are no longer needed saving on the cost of copper and the labor to install them.

Active Chilled Beams in Humid Climates

Thu, 30 Nov 2017 14:01:01 GMT

A common concern when considering chilled beams in any application is the potential for condensation forming on the coils causing droplets of water to fall in the conditioned space. This fear has resulted in the hesitation of some engineers to specify chilled beams, particularly in humid climates. Chilled beams can be applied successfully in all climates, regardless of outside air conditions. The humid outside air is dehumidified by the air handling unit(s) before it is delivered to the chilled beams, so the only sources of moisture that would concern the chilled beams are those within the conditioned space, typically the people occupying the space.

As with any HVAC system, there are parameters that must be considered when designing a project to include active chilled beams. According to the Active and Passive Beam Application Design Guide by ASHRAE “The implementation of an adequate chilled water control system, together with the supply of an adequate amount of correctly conditioned primary air, is sufficient to avoid the occurrence of condensation on the beams.” As long as the dew point temperature (a measure of humidity) of the room air is kept below the entering chilled water temperature it is impossible for condensation to form on the chilled beam.

In order for condensation to form on the chilled beam coil, the HVAC system would need to be performing well outside of the design parameters for an extended period of time. The Building Automation System (BAS) would sense this and take corrective actions before it becomes a problem by: 1) sending more primary air to the chilled beam by either opening an upstream VAV box or motorized damper (if applicable), 2) further dehumidifying the primary air at the air handler, 3) or raising the entering chilled water by several degrees so it is no longer below the room dew point. An additional level of protection can be gained by installing pipe condensation sensors at each chilled beam zone which close the control valve if condensation starts to form on the supply water of the chilled beam zone.

Air “leaking” into a building through a poor envelope or coming in through operable windows in perimeter zones is not ideal, but there are steps that can be taken to prevent condensation. In cases of buildings with a bad envelope, make sure to positively pressurize the inside of the building while assuming some infiltration in the load calculations for each room. Controls, such as window switches or room dew point sensors, can be used to stop the flow of chilled water or take other actions, when conditions warrant, in buildings with operable windows.

Why LEED Certified has more value than ever in the construction industry.

Wed, 08 Nov 2017 19:15:53 GMT

Leadership in Energy and Environmental Design (aka LEED), is a green building rating system that is the most widely used in the world. For those who are not familiar with LEED, “LEED provides a framework to create healthy, highly efficient and cost-saving green buildings. LEED certification is a globally recognized symbol of sustainability achievement.” (LEED is green building, 2017).

Buildings that obtain LEED certifications are attractive to more than just building owners that want to go green or save on energy costs, going green is gaining momentum within the construction industry considering that according to USGBC, “buildings account for almost 40 percent of national CO2 emissions and out-consume both the industrial and transportation sectors, but LEED-certified buildings have 34 percent lower CO2 emissions, consume 25 percent less energy and 11 percent less water, and have diverted more than 80 million tons of waste from landfills.” (Benefits of Green Building, 2016). There are also several tax incentive rebates available for energy efficient buildings that are appealing to building owners and the ROI for more efficient systems in a building, such as HVAC, is usually within 3 years.

LEED can also help to boost a buildings public image as being environmentally sensitive by reducing the amount of energy it uses. Additionally, LEED is very attractive to tenants that are seeking a comfortable, more energy efficient establishment. The US Green Building Council states, “LEED buildings have faster lease-up rates and may qualify for a host of incentives like tax rebates and zoning allowances. Not to mention they retain higher property values.” (Knox, N. 2015) It’s no wonder LEED has been booming throughout the construction industry.

To achieve LEED status, the Green Building Council uses a 110 point system (100 base points and 10 additional points) to award a Certified, Silver, Gold or Platinum status to a building. A breakdown of levels by points awarded is below:

Certified 40–49 points

Silver 50–59 points

Gold 60–79 points

Platinum 80 points and above

(USGBC , 2009)

LEED uses a Project Checklist to give credit toward certification that is broken down by specific categories. Each category is worth a maximum number of points and includes areas such as Water efficiency points, Atmosphere and Energy, and Materials and Resources used in the construction of a building. Points are given when a building provides documentation/proof of what they claim to have achieved under such categories and in the end the points are tallied up to determine a buildings eligibility for LEED Certification (Example of Project Checklist in Exhibit A).

Exhibit A (USGBC , 2009)

LEED is the international standard of excellence in green building. With recent Energy Star score ratings in place and environmental considerations, attractive rebates and energy yearly energy savings, becoming LEED certified has more value than ever in the construction industry.

What made Dadanco a LEED Gold facility

Wed, 01 Nov 2017 18:22:00 GMT

Dadanco’s LEED-GOLD headquarters is designed to showcase products while educating visitors on Dadanco technologies and applications. From the thermal test chamber to the demonstration rooms – our facility is designed to provide live product demonstrations of real world applications in order to aid in the decision-making process.

Leadership in Energy and Environmental Design (aka LEED), is a green building rating system that is the most widely used in the world (LEED is green building, 2017). To reach LEED GOLD, a facility must be awarded 60-79 points. Dadanco is proud to have achieved 69 points.

Here are just some of the areas Dadanco excelled in:

Exhibit A

Additionally, Dadanco was also awarded 6/6 points for innovation and design, including construction waste being 96% recycled. Dadanco’s Active Chilled Beams and Perimeter Induction Units played a large role in energy efficiency in achieving LEED status being awarded 34/37 points under “Energy and Atmosphere” including, 10/10 points for Optimize Energy Performance HVAC (Exhibit A).

Schedule a tour at Dadanco and learn the benefits of our energy efficient products and how they can help achieve LEED status for your next HVAC project.