491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

United CoolAir has been designing and fabricating highly flexible light commercial “niche” type air conditioning units since 

1988. This is a family-owned and operated American business with HVAC industry ties going back long before United 

CoolAir was formed. The company employs approximately 100 people and has a fabrication facility that comprises 80,000 

sq. ft. and an off-site warehouse of 20,000 sq. ft. located in York, PA.

United CoolAir commercial air conditioner units are applied systems that are specified by engineers, architects and 

design/build contractors to solve specific application requirements. Units are built-to-order and are not a commodity type 

of unit. We start with a basic model and add options or modify the sheet metal as needed to meet the specific application.

These units include a variety of styles, configurations and capabilities. Units are distributed through a network of 

approximately 60 independent representatives throughout the US, Canada and Puerto Rico.

In order to serve our “niche” of the market, a large inventory of parts and components are always kept on hand. A high 

percentage of our parts are sourced from US companies, as is all of our steel. While we attempt to handle all the design 

and fabrication in-house we out-source some specialty areas, such as paint for the cabinets.

Our “niche” in the market is that we provide an all-indoor modular system. There are many benefits to the end user for our 

type of products. The modularity means that the units typically can be taken into the structure without making building 

modifications. Systems arrive fully charged with refrigerant, thus lowering the installed cost and helping to insure a high 

quality system. Additionally, United CoolAir has designed and fabricated unique one-of-a-kind units for specific 

applications or OEM requirements, such as cooling controls on baggage X-ray units used at air ports.

Our systems are particularly well suited for renovation projects, add-on cooling, tenant fit out and replacement situations. 

United CoolAir units are typically used for:

Offices

Restaurants

Conference Rooms

Retail Spaces

Hotels

Bars

Fitness Centers

Laboratories

Lobbies

Communication Facilities

Plus other forms of commercial spaces needing air conditioning.

In addition to the commercial air conditioners United CoolAir also designs, fabricates and distributes portable / temporary 

cooling and heating units. These units are used for hospitality tents, temporary process cooling in manufacturing, spot 

cooling for computer rooms, dehumidification for ships in dry dock, shelters for first responders, and ground support for 

regional jets plus many other applications.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Double-Duct Air Conditioners

1. Have been around since mid-1950’s.

2. Units can be described as a “niche” product.

3. Entire system is located inside the building structure

4. Can be installed as a single package or as a split system

5. Primarily used for renovation or replacement applications.

6. Units are typically installed above drop ceilings (limited space). Competing for space in this 

area with duct work, water piping, wiring, communication cables, fire systems, etc. This 

application may be identified by some as being “space constrained”. However, the use of this 

term is not limited solely to the singular confine of the space the units get applied in, but also 

the doorways, elevators, hallways, etc. that the units must fit through in order to get the units 

into an existing building space.

7. Reference Sketch 2 for a graphic on typical application for a single package unit. Reference 

Sketch 3 for a graphic on typical application for a split system.

8. Applied only as commercial units (both single phase and 3 phase).

9. Units are built-to-order and are not stocked in any location.

10.Air for the condenser is ducted to and from the outside with field supplied extended ducting 

and louvers for the condenser air (inlet and outlet).

11. Description:

a. Factory made

b. Cooling Only or Heat Pump Configuration

c. Belt Drive Centrifugal Evaporator Blower

d. Belt Drive Centrifugal Condenser Blower

e. Evaporator Coil

f. Condensing Coil

g. Single or Multiple Compressor Circuits

h. Expansion Valve

12.All regulations have been defined with “outdoor units”. Outdoor units typically are configured 

and constructed using direct drive propeller fans. The units do not have to operate against any 

static pressure. The double-duct units typically utilize belt drive centrifugal blowers for the 

condenser air movement. They must overcome the pressure drop associated with the inlet and 

outlet louvers, ductwork, coil pressure drop and cabinet air pressure drop. Therefore, the 

horsepower to move the air is substantially higher.

13. Outdoor type units will typically have coils that have two or three rows. A double-duct 

condenser coil may be eight (8) rows deep. This means that the pressure drop across the coil 

alone is substantially more than the typical outdoor unit coil. 

14. Since the units are ducted on the condenser side there are limitations imposed by the 

structures as to the size of the duct work and louvers. Industry recommended installation 

guidelines dictate the velocity of air across louvers and in ducting. These help to establish what 

the coil size face area and other design parameters are to be. This size limitation affects the 

heat exchanger effectiveness directly and thus the size of the cabinet.

15. The testing standards are defined for units with propeller fans and no static pressure 

requirement. This means that the double-duct units must be tested at a point where they will 

never be operated.

16. The original product family encompassed thirteen (13) models that went from 1-ton up through 

15-tons. The requirement to achieve 13 SEER in the units forced the cabinet sizes to grow and 

diminished substantially the utility of the units. The new product family contains only six (6) 

models that range from 2 –tons up to 8-tons. Refer to Sketch 1 for a comparison of cabinet 

sizes. Outdoor condensing sections or rooftop units are not restricted by space limitations and 

can grow as needed to achieve higher efficiencies.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

17. The move to the higher efficiency models has reduced sales approximately 80 to 90%. Should 

ASHRAE 90.1-2013 be enacted, for the single package units at the higher 14 SEER efficiency 

level, an additional 45% of the sales will be lost. This loss of sales and unit utility we feel 

represents special hardship, inequity and unfair distribution of burdens.

18. The total sales for these type of units does not have any measurable impact on the national 

energy usage.

19. Due to the elimination of capacities and with the larger cabinet sizes there are no longer any 

like-for-like unit replacements for the end users. 

20.Since the original units are no longer available it is more likely that an end user may opt to 

repair an old unit rather than replace it with a more efficient model. This defeats the purpose of 

having more efficient equipment available.

21. United CoolAir has pursued higher efficiency components to aid in gaining efficiency while 

retaining the utility of the units. 

a. Some coil technologies are not available for small manufacturers, such as microchannel 

coils. Microchannel coil selection software does not model the performance very well. 

Our experience has been that multiple coil samples must be tested to achieve an 

acceptable selection. As a small manufacturer, that does not have a test lab, this testing 

becomes too expensive to justify for development of an entire product family. 

Additionally, most of the microchannel coil vendors want orders at quantity levels that 

far exceed our annual demand.

b. Smaller tube coils are just now becoming available from our vendors. We are looking at 

this technology, but it is new for UCA and remains to be seen if it will accomplish what 

needs to be achieved.

c. High efficiency motors have been used where available.

d. Currently looking at higher efficiency blowers / motor combinations. Unfortunately these 

are not available from any US manufacturer. The lead-time is very long to get the 

blowers from Germany. The cost will add even more (several hundred dollars) to the 

already bloated price for the current models.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Sketch 1 Unit Size Comparison

 Standard Efficiency High Efficiency

Tons

Compr. 

Qty H W L

Cu. 

Ft. Tons

Compr.

Qty H W L Cu. Ft.

1 1 16 35-15/16 51-5/8 17.18 1 NLA

1.5 1 16 35-15/16 51-5/8 17.18 1.5 NLA

2 1 22 47-3/8 66-5/16 40.21 2 1 22 56 76 54.19

3 1 22 47-3/8 66-5/16 40.21 3 1 22 56 76 54.19

4 1 22 47-3/8 66-5/16 40.21 4 1 25 64 86 79.63 

5 1 22 47-3/8 66-5/16 40.21 5 1 25 64 86 79.63

4 2 27 55-3/8 71-3/4 62.08 4 NLA

5 2 27 55-3/8 71-3/4 62.08 5 NLA

6 2 27 55-3/8 71-3/4 62.08 6 2 32 70-1/2 108-1/2 141.65

8 2 27 55-3/8 71-3/4 62.08 8 2 32 70-1/2 108-1/2 141.65

10 2 29 70-5/8 80-3/4 95.71 10 NLA

12 3 29 70-5/8 80-3/4 95.71 12 NLA

15 3 29 70-5/8 80-3/4 95.71 15 NLA

High Efficiency

Tons Compr. Qty

1 NLA

1.5 NLA

2 1

3 1

4 1

5 1

4 NLA

5 NLA

6 2

8 2

10 NLA

12 NLA

15 NLA

Standard Efficiency

Tons Compr. Qty

1 1

1.5 1

2 1

3 1

4 1

5 1

4 2

5 2

6 2

8 2

10 2

12 3

15 3

Size Diff.

Cu. Ft. %

13.98 134.8

13.98 134.8

39.42 198.0

39.42 198.0

79.57 228.2

79.57 228.2
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Operating Cost Analysis

A 5-Ton single compressor air-cooled system was selected for the analysis. This was done because there was a 

5-ton unit in the standard efficiency and also in the high efficiency product families. The 5-ton unit also represents 

a high percentage of the product family sales mix.

HVACOPCOST software was selected from the internet. This is software available to all people and companies 

and therefore does not provide any bias on the part of United CoolAir. The software is designed to handle 

analysis based on SEER ratings, unit tons, electric rates and cooling hours. The software provides the cooling 

hours based on the city location.

Electric rates were obtained from ELECTRICCHOICE.COM. Commercial values for 2013 were selected for a 

number of cities.

The comparison was made based on the current 13 SEER minimum rating and a 10 SEER rating. The 10 SEER 

rating was an arbitrary selection, but it is close to what the requested energy efficiency level is. It should be noted 

that this efficiency level is higher than the original Standard Efficiency level unit. The operating cost software only 

allows determination based on SEER levels.

A cost difference of $2,500 has been used as this is the price difference between the old Standard Efficiency 

model and a High Efficiency model with an anticipated mark-up from the Distributor to the purchaser.

A 3 year period was selected as the target payback period for the end user to re-coup the additional cost.

Chart 1 below plots the cooling hours based on the various electric rates against the 3 year operating cost 

savings. This chart illustrates that only at higher electric rates and high cooling hours is there any opportunity to 

recover the added first cost.

Chart 2 below plots the selected cities against cooling hours and operating savings. Even Miami with the highest 

cooling hours cannot achieve a payback in 3 years based on operating cost savings.

Table 1 tabulates the operating cost savings for the first three years. An average increase of 2% in electric rates 

was used for years 2 and 3. Additional rates above the 2013 levels are also listed.

The operating cost savings when going from a 10 SEER model to a 13 SEER model do not provide enough 

savings based on current electric rates and cooling hours. The added cost (approximately $2500 for a 5-ton 

model) for the higher efficiency cannot be justified based on operating savings.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Chart 1 – Cooling Hours vs. 3-Year Operating Savings
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Chart 2 – Cooling Hours vs. Operating Savings
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Orig. SEER 10

Hours New SEER 13

Location Cents / KWH Yr 1 Yr 2 Yr 3 Total

1320 11 $249 $254 $259 $762

Washington, DC 12 $271 $276 $282 $829

13 $295 $301 $307 $903

14 $317 $323 $330 $970

15 $339 $346 $353 $1,037

2127 9 $329 $336 $342 $1,007

Charleston, SC 10 $364 $371 $379 $1,114

11 $401 $409 $417 $1,227

12 $437 $446 $455 $1,337

13 $474 $483 $493 $1,451

1089 15 $280 $286 $291 $857

New York, NY 16 $298 $304 $310 $912

17 $318 $324 $331 $973

18 $336 $343 $350 $1,028

19 $354 $361 $368 $1,083

683 7 $82 $84 $85 $251

Chicago, IL 8 $94 $96 $98 $288

9 $106 $108 $110 $324

10 $117 $119 $122 $358

11 $129 $132 $134 $395

1215 8 $166 $169 $173 $508

St. Louis, MO 9 $187 $191 $195 $572

10 $208 $212 $216 $637

11 $229 $234 $238 $701

12 $250 $255 $260 $765

2209 7 $265 $270 $276 $811

Houston, TX 8 $303 $309 $315 $927

9 $341 $348 $355 $1,044

10 $378 $386 $393 $1,157

11 $417 $425 $434 $1,276

282 7 $33 $34 $34 $101

Seattle, WA 8 $38 $39 $40 $116

9 $43 $44 $45 $132

10 $48 $49 $50 $147

11 $53 $54 $55 $162

379 8 $52 $53 $54 $159

Portland, OR 9 $59 $60 $61 $181

10 $65 $66 $68 $199

11 $71 $72 $74 $217

12 $78 $80 $81 $239

1530 14 $367 $374 $382 $1,123

Los Angeles, CA 15 $393 $401 $409 $1,203

16 $420 $428 $437 $1,285

17 $446 $455 $464 $1,365

18 $472 $481 $491 $1,445

2141 9 $330 $337 $343 $1,010

Phoenix, AZ 10 $367 $374 $382 $1,123

11 $404 $412 $420 $1,236

12 $441 $450 $459 $1,350

13 $477 $487 $496 $1,460

3931 9 $607 $619 $632 $1,858

Miami, FL 10 $674 $687 $701 $2,063

11 $741 $756 $771 $2,268

12 $808 $824 $841 $2,473

13 $876 $894 $911 $2,681

Average Electric Price Increase 2% (Years 2 & 3)

Table 1 – Summation of Operating Cost Savings
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Impacts of Higher Efficiency Levels on Double-Duct Air Conditioners

A. The cabinet sizes have grown substantially (Ref. Sketch 1). This means that the units, defined by capacity size, 

can no longer fit into the same space. The tabulation associated with Sketch 1 shows that the cabinets have 

grown from 134% to 228% of the comparable unit capacities of the Standard Efficiency models. The 6 & 8 ton 

cabinets are more than double the older cabinet size and exceed the old 15 ton cabinet size.

B. Like-for-like units can no longer be provided due to the larger cabinet sizes.

C. Capacity sizes have been lost: 1, 1-1/2, 10, 12 and 15-ton models.

D. End users are more likely to repair a unit, rather than replacing with a more efficient system. The desire for energy 

savings will not be achieved.

E. Unit prices have increased substantially. A 5-ton unit now costs approximately $2,500 more.

F. Operating cost savings for a 10 SEER unit versus a 13 SEER unit cannot re-coup the increased unit cost in 3 

years or less. In some areas of the U.S. the operating cost savings may not be re-couped during the life time of 

the equipment.

G. Sales of the double-duct units have dropped substantially.

H. The ASHRAE 90.1-2013 standard will erode more sales because of the higher efficiency levels. The requirement 

for the single package units to achieve 14 SEER, for units < 65 MBH, will eliminate another 45% of the market.

I. United CoolAir is aware of one manufacturer that stopped producing these units several years ago because they 

could not engineer units to achieve the higher efficiency levels.

J. A high majority of the impact on double-duct air conditioners falls on small businesses.

K. Technology to achieve the higher efficiency levels will raise the cost substantially more. Some technology means 

going outside the U.S. for components.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Standard vs. Burdens

The following is a summary of “litmus test” questions that are to be analyzed to determine if a standard is justified. 

Comments listed are relative to the energy efficiency requirements only for horizontal double-duct type air conditioners.

(I) The economic impact of the standard on the manufacturers and on the consumers of the products subject to such 

standard

a. Manufacturing costs have been raised and thus the end price to the consumer. 

b. Costs, relative to high production volume units, went up proportionately more for the same efficiency level 

achievement.

c. Sales and revenues for the small manufacturers have been substantially reduced.

d. The cost for compliance for small manufacturers must be spread out across a substantially less unit 

volume (less than a hundred units) compared to high volume (thousands of units) type units.

(II) The savings in operating costs throughout the estimated average life of the product in the type (or class)

compared to any increase in the price of, or in the initial charges for, or maintenance expenses of, the products 

which are likely to result from the imposition of the standard

a. The increased cost cannot be recovered in a reasonable period of time (3 years) based on current electric 

rates from around the country and the amount of cooling hours.

b. In many locations the recovery of the higher costs may take 10 to 15 years or more on a unit with a 

projected lifetime of 15 years. It must be noted that due to the nature of commercial unit applications, a 

unit lifetime may actually be before any recovery of the energy cost savings is achieved.

(III) The total projected amount of energy savings likely to result directly from the imposition of the standard

a. The estimated total market of the horizontal double-duct type air conditioners represents approximately 

< 0.01% of the total air conditioner market. 

b. The increased efficiency level for these units does not have any measurable impact on the national 

electrical energy consumption.

(IV) Any lessening of the utility or the performance of the products likely to result from the imposition of the standard

a. The size of the equipment has grown substantially due to the higher efficiency requirements and the 

available technology to achieve the efficiency. (See sketch 1)

b. The larger size means that the units cannot fit into the same space where they once did. 

c. Like-for-like replacement is not possible in many situations.

d. The renovation and replacement market, which is where a high majority of these units are applied, have 

more stringent / restrictive application parameters versus new construction.

e. The larger sizes of units above 8-ton are no longer available. The smaller 1 and 1-1/2 ton models are also 

no longer available.

f. A categorization of “space constrained” should be considered. These units when placed above a drop 

ceiling are competing for space with duct work, water piping, electrical services, communication cabling, 

fire sprinkler systems, etc. Additionally, getting the units into the space is also an additional parameter 

under space constrained considerations.

(V) The impact of any lessening of competition, as determined in writing by the Attorney General, that is likely to 

result from the imposition of the standard

a. United CoolAir is aware of one manufacturer that stopped producing the horizontal double-duct units 

because of the higher energy efficiency requirements.

b. The increased cost of these units versus other types of equipment, that is not as well suited to the 

application, reduces the competitive nature of business.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

c. No major manufacturer makes these types of products so the entire customer base is dependent upon 

small manufacturers to fulfill the needs.

d. Small manufacturers do not have their own test facilities. As a result, they are limited as to what testing 

they can get accomplished based on available resources versus what the major suppliers can accomplish 

using their in-house testing capabilities and resources.

(VI) The need for national energy conservation

a. See (III) above

(VII) Other factors the Secretary considers relevant

a. Cabinet size limits, condenser coil size requirements and the use of a centrifugal blower on the 

condenser air side represent the key items that differentiate these units from other air conditioners and 

what makes it difficult to achieve parity of efficiency.

b. Need to consider that due to the loss of specific capacities and the inability to get replacement units into 

the same space, repairs are more likely to result rather than a replacement with a unit that is more 

efficient.

c. Small manufacturers typically do not have the access to newer technology required to make the units 

more efficient at a reasonable price. Thusly, the small manufacturers are more dependent upon vendors 

to be able to provide the components required to achieve the performance levels.

d. Some of the newer technologies, such as one type of heat exchanger, require more testing of more units 

due to the lack of accurate computer performance modeling. As noted above, the small manufacturers 

have fewer testing resources available and the costs would go up even more for outsourced testing.

e. One of the newer technologies required to achieve the higher efficiency levels and keep the unit size 

small, is not currently available from any US manufacturers.

f. Vendors that provide a key component to the small manufacturers could not justify the new technology 

until 2014.

g. Commercial units are typically used more (higher run hours) during the year than residential models. 

Therefore, there is less of a seasonality consideration. Having a rating standard for these types of units 

as an EER target instead of the SEER type target would lessen the amount of testing required for the 

small manufacturers.

h. Standards have been developed or created based on the high volume type units that are configured with 

outdoor propeller air movement for the condenser / condensing section. The indoor condenser / 

condensing sections must use a centrifugal blower to handle the increased pressure drop of the coil 

configuration, louvers and duct losses associated with this type of product. This difference in technology 

has not been taken into account when establishing “one size fits all” efficiency levels.

i. All the existing test standards for the industry are based on the outdoor propeller technology. This forces 

the centrifugal technology type units into being tested at a point where they were not designed to operate.

j. Max-Tech refers to the maximum technology that can be employed to achieve the highest energy 

efficiency. The actual level of efficiency is below the max-tech level. It is our belief that for the horizontal 

double-duct units the max-tech level where the unit size and character changes and utility is lost, is less 

than 11 EER. We would propose an EER level of 10 be set for the horizontal double-duct systems (single 

phase and three phase). 

k. Some might argue that this would represent back sliding for efficiency. Our position on this is that the 

rules and standards have all been written around an “outdoor” unit. A single all inclusive rule does not and

cannot encompass all the unit types. Since these units are located indoors, a separate product category 

should have been created to support this product type. Efforts are under way to get the testing standards 

updated to include these types of units.

l. Similar type units currently exist as vertical, floor mounted, ducted condenser, style configurations in the 

SPVAC Product Classification with Energy Efficiency Levels of 9.0 EER (< 65 MBH), 8.9 EER (≥ 65 MBH 

and < 135 MBH) and 8.6 EER (≥ 135 MBH and < 240 MBH). ASHRAE 90.1-2013 has proposed raising 

the efficiency level of these units to 10 EER for all capacities.
491 E. Princess Street • York, PA 17403 • 717-843-4311 • Fax: 717-854-4462 • www.unitedcoolair.com

Request for Double-Duct Air-Cooled Air Conditioners

A. Exempt the double-duct units until:

a. The applicable industry standards are changed to include the ducted condensing sections.

b. The verbiage in all the Federal rules and regulations is changed from describing systems solely with or as 

“outdoor units”.

c. Establish a new product class – “Horizontal Double-Duct Air-Cooled”:

1.Capacity range should cover all units < 180 MBH.

2.Product class should include both single phase and three phase units.

3.Units are horizontal indoor configuration only.

4. Efficiency level should be the same for the single package and the split systems.

5.Set the efficiency level at 10 EER for all sizes and electrical power source.

B. Target 1/1/2016 to have the above accomplished.