Different Types of Steam Coils?

There are two types of steam coils:  standard steam coil, which is used in most reheat applications, and steam distributing coils, which are used in applications where the entering air temperature is below 40 F degrees.  Many times, this type of coil is known as a “non-freeze” coil, but that name is very misleading because there is no such thing as “non-freeze”. 

Standard Steam

Standard steam coils operate a lot like hot water coils, but the construction is very different even though the coils may appear to be constructed the same.  The supply and return connections are often on the same end like a hot water coil.  But, steam is very different than hot water and the coil must be built for steam and circuited for steam.  Steam is always more erosive than hot water.  The brazing and tube wall thickness must account for steam. ALWAYS remember that even low pressure steam is more erosive than hot water and a steam coil needs to be built accordingly.

Steam Distributing (Non-Freeze)

Steam distributing coils are a completely different coil because they are built with a tube within a tube construction. Every place that you see an outside tube or header, there is an inside tube and header that you can’t see. The steam on the inner tube keeps the condensate in the outer tube from freezing.  The purpose of the Steam Coiloriginal coil design was to distribute the steam evenly along the length of the coil and to eliminate and dead spots on the coil.  A byproduct of this coil was also found.  The coils didn’t freeze nearly as easily as the standard steam coil., so the coils became known as “non-freeze”, which as mentioned, is not totally correct.  Any coil can freeze under the right conditions.  But, this design is what needs to be used when the entering air is under 40F degrees. 

Steam Coil Design

Steam coil designs can be very tricky.  Steam coils are totally a function of the system and installation while other coils operate more independently of the system.  There needs correctly designed traps, and they need to be installed in the right place and depth in the system.  Often, vacuum breakers are also needed in the system.  The piping must be installed correctly to make sure the steam in entering the coil and not the condensate.  Even with all of those factors, you need a correctly designed steam coil that matches the steam pressure, length of the coil, and the entering air temperature.  Coils can freeze easily.  Coils can be too long in length and the steam cannot travel the length of the coil and distribute evenly.  Condensate can easily be trapped somewhere in the coil and the result is water hammer. 

Capital Coil & Air has years of experience designing steam coils, and is here to answer any questions and help to design the right coil for your project! 

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HEATING SEASON WILL SOON BE UPON US

 


HEATING SEASON WILL SOON BE UPON US

The real ability and competency in selecting hot water coils or any other heating coil is to know and understand the products that are available. Our goal here is to help simplify your selection process. Just as you’d spend time researching cars before a purchase, you want to be as educated of a buyer as possible!Hot Water Coil

HOT WATER COILS

The HVAC industry classifies coils as “Hot Water” if they are (1) or (2) rows deep, and “Chilled Water” if the coil is (3) to (10) rows deep. One important fact to remember is that whether the water is hot or cold, a water coil is still just a water coil. Just because you do not need as many rows for hot water applications, all water coils are built the same. Tubes can be 5/8 ” copper or 1/2 ” copper, and water can travel through the coil’s tubes at temperatures up to 200˚F. Capital Coil’s selection program is very user-friendly and can greatly assist in your selection process.

STANDARD STEAM COILS

While steam coils look very similar to water coils, the construction and circuiting of the coil are usually very different. Specifically, the brazing for the tubes and headers has a higher percentage of silver solder in the brazing. The tubes are generally thicker (.025”), and the circuiting of the coil minimizes the passes to allow for easy condensate removal. Unless you have (2) PSI or (5) PSI steam, hot water coils and steam coils are not interchangeable! Steam pressure is extremely important to take into account.

STEAM DISTRIBUTING COILS  “NON-FREEZE”

The construction of a “non-freeze” coil is completely different than that of a water coil or standard steam coil. Steam Distributing coils are manufactured as a tube within a tube. This application should always be used when the entering air temperature on a coil is 40˚F or below. There are (2) types of designs for steam distributing coils. They can be constructed with 5/8” (outer-tube) / 3/8” (inner-tube)  &  1” (outer-tube) / 5/8” (inner-tube).  A Capital Coil sales rep is always available to help with proper selections.

HOT WATER BOOSTER COILS

Hot water booster coils are primarily used in duct applications for reheat purposes. In addition to hot water, booster coils can also be used for low pressure steam. The best part is that Capital Coil has a standard (1) week lead time for booster coils. We value speed and quality as much as you.

Capital Coil manufactures all of the above for whatever heating application you may need. All coils are also available on our quick-ship program – if you need your coil built in 3, 5, or 10 days. Capital Coil & Air welcomes the chance to work with you, and be your source for quick answers and immediate service. Please give us a call on your next project!

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Does Your HVAC Coil Selection Program Leave You With More Questions Than Answers?

At Capital Coil & Air, we have an accurate and user-friendly coil selection program to select and choose coils. Of course, making good selections is based on having years of experience working with coils of all types and sizes, and Coil Selection Programwe at Capital Coil have that necessary expertise.

When designing a coil, the object is to balance cost and performance together, and that is one area in which we can greatly assist. We do not always choose the cheapest coil because the cheapest coil in almost never the best coil. There are always pressure drops, materials of construction, performance requirements and a host of other things that all play into good or bad coil selections. These are even more relevant in the coil replacement market!

The object is not to duplicate a problem with a coil, but to instead solve the problem and make the coil perform better and last longer. This requires problem solving and making selections that are not always “in the box”.

Part of any successful selection process is having a good selection program to help you. But what makes a program good? First and foremost, you must get the correct results, or you have bad information that is also useless. But apart from that, the selection program must be easy to navigate through. There are “red lights” and “stop signs” built into the program to keep you from making bad selections. Our selection program has most, if not all, coil configurations and styles that you’re likely to run across. We are confident that you’ll find the selection program user-friendly, helpful, and one that makes you want to do business with Capital Coil & Air.

You simply have to click here to request the program, and we will send you an email in response with an activation code and a link to download the program. Of course we are always here to assist you in any selections that you make, or to give you some engineering suggestions and recommendations. Thanks for giving us the opportunity to help you!

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Stock Hot Water Coil – Quick Buyers Guide

Hot Water Coils

Depending on the specific project, selecting the appropriate Hot Water Coil can go one of two ways:  1) costly and complicated or 2) cheap and rather straight-forward. If you’re a representative or contractor reading this, you understand this fact all too well. And if you’ve dealt with us, you know that we much prefer going the second route rather than the first.  Considering the complexity of other types of coils, hot water coils should be as easy for to purchase and get delivered as they are for the manufacturer to build and keep in stock. So…why is it so hard to get your hot water coils shipped to where you need them when you need them?

Capital Coil & Air decided to create a quick buyers guide to when selecting and purchasing Stock Booster Coil Replacements :

  • First and foremost, you need to determine whether the booster coil needs to be 1 or 2 rows deep. Keep in mind that a 2 row booster coil will always generate substantially more BTU’s than a 1 row booster coil, but will also cause your air pressure drop to rise.
  • Generally speaking, booster coils are primarily installed someplace in the ductwork. If your duct size doesn’t match exactly with what we can build a good rule of thumb is to request your coils be built slightly larger than the ducts where they are going to be installed.
  • Booster coils are offered in sizes anywhere from 6” x 6” to 30” X 72”. Booster coils are 1 or 2 row coils that are available in 60 sizes.  Flanged or Slip & Drive casings are available on every size to meet your needs.
  • While most manufacturers claim they have “booster coils in stock”, and then ship in a week, we actually have (30) sizes in stock ready to ship the next day!

Whether you need (1) hot water coil or (200) hot water coils, Capital Coil & Air has the most competitive pricing in the business with the best lead times. Please see our Booster Coil Product Page. Most companies don’t want to bother with hot water coils.  No one does hot water coils better than Capital Coil & Air!

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What Does “Splitting” A DX (Evaporator) Coil Mean?

“Splitting” a DX (Evaporator) coil is one of the toughest concepts to understand in the coil business. “Splitting” the coil simply means that (2) compressors can operate off of the same coil. One obvious advantage, or reason that you might “split” a DX coil is that you can shut down (1) of the compressors when the cooling load does not require it. This in turn saves energy, which saves $ when the cooling load is not operating at maximum design conditions. For example, let’s use a coil that is designed to give you (40) tons, but the coil is split so that (2) 20-ton compressors are feeding the same coil. If you only require ½ of the maximum load on any given day, you can shut down (1) compressor completely and operate the other one at 100%. This is a money-saving feature that you need to be aware of if you deal with DX coils on a regular basis. This requires special circuiting arrangements, and this is where the confusion starts with most folks. There are three primary ways to deal with this:

FACE SPLIT

Splitting the coil is nothing more than putting (2) completely separate fin/tube packs (coils) into one common casing. When you hear the term “face-splitting” a coil, you are drawing a horizontal line from left to right across the face of the coil and dividing the coil into a top and bottom half. It is like having two separate coils in one casing in that each half is circuited by itself. You hook up (1) compressor for the top half, and (1) compressor for the bottom.

In practice, this configuration is no longer used with much frequency because this arrangement leads to air being directed across the entire face of the coil. This disadvantage is especially apparent when only one half of the coil is in use because you’ll need a complicated damper/duct system to ensure that air is only directed to that portion of the coil in operation.

Row Split

“Row splitting” a coil is dividing the coil by drawing a line vertically and putting some portion of the total rows in (1) circuit, while putting the remaining rows in the other circuit. With this configuration, the air passes across the entire face of the coil, and will always pass across the rows that are in operation.

Please be aware that this configuration also comes with certain issues in that this kind of split makes it very hard to achieve a true 50/50 split. Let’s use an (8) row coil as an example. You would like to “row split” this coil with (4) rows/circuit, which would appear to be a perfect 50/50 split. The problem here is that the first (4) rows, located closest to the entering air, pick up a much higher portion of the load than the last (4) rows. In actuality, this coil’s split is closer to 66% / 34%, which will not match the 50/50 compressors. Another option is try to split the coil between (3) & (5) rows. While not 50/50 either, this configuration is closer. However, a new challenge arises because you have now created a coil that is very difficult to build and correctly circuit. In short, you need almost perfect conditions along with a degree of luck to achieve a true 50/50 split using this method.

Intertwined Circuiting

The most common to split coils today is to “intertwine” the circuiting. This means that every alternate tube in the coil is included in (1) circuit, while the other tubes are included in the (2nd) circuit. For example, tubes 1, 3,5,7,9, etc. in the first row are combined with tubes 2, 4, 6,8,10, etc. in the second row. The same tubes in succeeding rows form (1) circuit. You are essentially including every alternate tube in the entire coil into (1) circuit, which (1) compressoDX (Evaporator) Coilsr will operate. All of the remaining tubes not included in the first circuit will now encompass the second circuit.

The advantage of this configuration is that the air passes across the entire face of the coil, and, if one of the compressors is on, there are always tubes in operation. Every split is now exactly 50/50 because it cannot be any other way. Most DX coils are now configured in this manner due to these advantages.

 

Capital Coil & Air has years of experience measuring, designing and building almost every OEM DX coil that you’ll come across, so please let us help you on your next project. We want to be your replacement coil experts and look forward to the opportunity.

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Tired Of Wondering If Quick-Ships Will Be Available When You Need Them Most?

With summer seemingly flying by, chances are that you have been getting urgent requests by customers to order replacement coils and have them installed within very tight windows. You’ll run into this with schools for example when, understandably, they’d like to handle everything during the summer break. If that happens, what next? You can call the OEM, but more times than not, they are not flexible or nimble enough to handle your request/emergency within the allotted time-frame. DX Coil

Why is this? Many manufacturers take on a glut of OEM business, or other large projects with small profit margins. In many cases they do this simply to keep the factory running during the slower periods of the year. This has the effect of delaying standard lead times, and in many cases, cancelling quick-ships altogether. It is very hard to do business with companies that make themselves unavailable when you need them the most.

Other cases may simply be logistical. For example, an OEM might be transferring plant locations. They will eventually get back online, but how does that help you in your current “emergency” situation?

Quick-ships are generally based on emergency conditions, and that is precisely the worst time to discover that your regular supplier has suspended their quick-ships. When we call Capital Coil reliable and dependable, one of the main reasons is because of our ability to keep our quick-ship program open 12 months/year. Capital Coil does not try to be all things to all customers, but quick-ships are an integral part of our business. Keeping our quick-ship program available all year is a top priority, and this has allowed us to hit 99.9% of our quick-ship requests over the last (3) years – an unfortunate forklift mistake makes up the other .1%. 5.5 months into 2019, approximately 75% of all orders have been quick-ships, and they have either all been completed on time, or are 100% on schedule.

An RFQ that sits on a desk unanswered is useless to everyone involved. If you need a quote, you’ll have your price and any required submittals that same day. It really is that simple and easy! Working with Capital Coil removes many of the annoying and unannounced shut-downs that come with other manufacturers, so please let us help you when you need it the most!

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Top 10 Tips For Measuring Coils

1. When measuring coils, performance has very little to do with accurately measuring for replacement coils. Fitting the coil in the existing space with the least amount of labor has everything to do with measuring a coil.  If you duplicate the coil in almost every respect, the performance will match and take care of itself.  New is always more efficient than old.

2.  If you’re ever in doubt about a dimension, smaller is always better than bigger. You can always “safe off” around any coil as long as you can fit it in the space.  If a coil is too big, it makes a really ugly coffee table in your shop.  Too big is the enemy of measuring coils.

Chilled Water Coil

3.  The fin height and fin length are not the determining factors in measuring a coil. The overall casing dimensions are the most important, and you work backwards to determine fin dimensions.

4.  The depth of any coil is the total casing depth in the direction of airflow. The height is the number of tubes high in any row.  Depth is a function of rows deep and height is a function of tubes in a row.

5.  Overall length (OAL) is not the fin length and it’s not the casing length. It is the length from the return bends to include the headers that are inside the unit.  Again, it is necessary to work backwards to get the other dimensions once you know this critical dimension.

6.  Circuiting is the number of tubes connected to the supply header. Generally, you just want to count the number of tubes connected to the header and that will tell you whether it’s full, half, or even a double circuit.  It does not matter how the return bends are configured.  Your goal is to count the number of supply tubes and all performance is based on that.

7.  Fins are measured in fins per inch. Hold a tape measure up to the coils and count the number of fins in one inch.  If you can’t get in to take the measurement, a safe rule of thumb is 10-12 fins/inch.  That will work on almost every coil.  The exception to that rule is a condenser coil.  14-16 fins/inch on a condenser coil is usually pretty safe.

8.  Connection locations are difficult only if you are using the existing piping in the system (which are welded). Copper piping is brazed and can be changed easily.  If a system is old and the piping is being replaced as well as the coil, the connection location is not a major deal.  It’s very easy to match up!

9.  With replacement coils, the concept of “left hand vs. right hand” doesn’t actually exist. Connections are “top left-bottom right” or vice versa.  Ideally, all coils should be counter-flow which means that the water and air flow in opposite directions.  The air hits row one first and the water is piped into row eight first.  However, there are lots of installations that are piped backwards, and they work just fine.  Just match them up, and the coil’s performance will be equal to the old coil.

10.  Connections are not measured from the top of the header! They are measured from the top of the casing to the centerline of the connection.  Or the bottom of the casing to the centerline.  You need a point of reference, and the header height can be anything just as long as it doesn’t stick above or below the casing height.

All of the above “suggestions” or “secrets” are in no particular order.  They are just things that you should know to ensure that you are selecting the correct replacement coil. While most seem like common sense, your best bet is to talk with the sales team at Capital Coil & Air, who can walk your through the entire process and help you to fill out coil drawings when trying to measure the dimensions.

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Construction Vs Performance: Need To Know Terminology

If you have ever dealt with commercial HVAC coils, you have probably come across numerous “industry terms” with little to no explanation as to what these terms actually mean. To further confuse you, some verbiage is specific to the actual construction of the coil, while others are only important when determining a coil’s performance. If you do not work with coils on a frequent basis, it is hard to decipher what exactly these terms are referring to. To help translate this industry verbiage, Capital Coil & Air has come up with a list/glossary of the most common and relevant terms that you are likely to come across on most coil jobs.

 Performance

  • AHRI (Air-Conditioning, Heating, and Refrigeration Institute): Developed industry standards for air conditioning, heating, and commercial refrigeration equipment. All of CCA’s coils are AHRI-certified, so you know you’re getting dependable quality and performance in every product.
  • Air Pressure Drop: Air Pressure Drop is a result of Flow Rate, Fin Type, Rows and Fins per Inch. In addition, on either Chilled Water or DX (Evaporator) Coils, the air pressure drop is affected by the condensate on the fin surface.
  • Airflow (CFM): Cubic Feet per Minute, which refers to the amount of air flowing across the coil. A typical cooling coil should produce between 400-500 FPM. You want to avoid exceeding 550 FPM on all Chilled Water & DX Coils. Too little airflow means your coil is not running at peak capacity, while too much airflow can result in excess water carryover.
  • Entering Air Dry Bulb Temperature: You guessed it! The sensible temperature of the air entering the coil.
  • Leaving Air Dry Bulb Temperature: The sensible temperature of the air leaving the coil. Why does this matter? If you are trying to replace and duplicate a coil’s performance, making sure that your new coil can meet or exceed the old coil’s leaving air temperature is a crucial factor.
  • Entering Air Wet Bulb Temperature: This temperature signifies the amount of moisture in the air entering the coil.
  • Leaving Air Wet Bulb Temperature: Conversely, this temperature refers to the amount of moisture in the air exiting the coil.
  • Total Capacity: The sum total of a coil’s sensible and latent capacities.
  • Steam Pressure: Only relevant to steam coils, the saturated steam pressure at the inlet of a steam coil. Steam pressure is usually relative to the steam coil’s total capacity.
  • Steam Condensate: Again, applies only to steam coils and is a measure of the condensate generated by that steam coil.

Construction

  • Casing Type: The supporting metal structure for tubes and the header. Different casing options include Flanged (standard), Slip & Drive, Inverted, Stackable, and Collared End Plates & End Plates only. Steam Coils require Pitched Casing to allow for adequate condensation drainage.
  • Casing Material: The coil’s casing can be made from a variety of different materials. Options include: 14 or 16 Gauge, Galvanized Steel; 304 or 316 Stainless Steel; Copper & Aluminum. Please contact us directly to see about options other than those listed.
  • Connection Material And Type: Standard connection types are MPT (Male Pipe Thread, threaded on the outside), FPT (Female Pipe Thread, threaded on the inside), ODS (Sweat Connections, no threads)
    • Water & Steam Coils: Copper MPT, FPT, (with options for steel MPT & FPT)
    • DX & Condenser Coils: Copper ODS normally
  • Circuiting/FeedsCircuiting is determined by the number of tubes in each row divided by the total number of tubes fed (or feeds). Feeds are also known as the number of parallel circuits in the coils. Always feel free to call Capital Coil’s sales department with any circuiting-related questions.
    • Water Coil: Enter the coil’s performance data into CCA’s coil selection program, and select the “auto” sizing option to determine the optimal number of feeds.
    • Condenser Coil: Since the condenser is a rating program only, the user must enter a value for the number of feeds. A good rule of thumb is to have approximately 8 – 15 psi refrigerant pressure drop in the condenser.
    • DX Coil: Enter coil’s performance data into CCA’s coil selection program, and select the “auto” sizing option to determine the optimal number of feeds.
    • Steam: Always a full or double circuit
  • Fin Height: FH is measured in the direction of the fins, or perpendicular to the direction of the tubes.Water Coil
    • For 5/8″ tube coils, fin heights are available in increments of 1.5”
    • For 1/2″ tube coils, fin heights are available in increments of 1.25”
    • For 3/8″ tube coils fins are available in 1.00″ increments
  • Fin Length: FL is always measured in the direction of the tubes, regardless of which direction the tubes are running.
  • Fins per Inch: Represents the fin spacing on the coil. The number of fins per inch is an essential component when ordering a replacement. Using a standard ruler, simply count the number of fins per inch on the coil.
  • Number of Rows: Rows represent the coil depth and are always counted in the direction of the air flow, regardless of how the coil is mounted. Count the number of rows by viewing the header end or the return bend end of the coil.
  • Hand (Left or Right): A coil’s hand is determined by the direction of the airflow. Look at the finned area of the coil, and if the air is hitting you in the back of the head, look to see which side of the coil the headers are located. If the header(s) are located on the right side, then the coil is right-handed. Likewise, if the header(s) is located on the left side, it is left-handed. An important point to remember is that you always want the airflow to run counter to fluids, refrigerant and steam flow.

Miscellaneous

  • Laminar Flow: Tends to occur at lower fluid velocities, below a threshold at which it becomes turbulent. In other words, laminar flow is smooth while turbulent flow is rough. Greater heat transfer occurs in a coil with turbulent flow as opposed to a calm, laminar flow.
  • Dry Weight: The estimated weight of the coil; not counting internal fluids or packaging.

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Chilled Water Coil Circuiting Made Easy

Chilled Water Coil

Circuiting a chilled water coil is one of life’s great challenges in the coil business. You’re bound to run across folks with years of experience in the industry that can not effectively explain this concept. While not the most exciting of subjects, the necessity of circuiting chilled water coils can not be overstated. Capital Coil & Air has attempted to simplify the idea of circuiting as much as possible.

For starters, circuiting a chilled water coil is ultimately up to the performance of that coil. Circuiting is really a balancing act of tube velocity and pressure drop. In other words, think of a coil as a matrix. Each coil has a specific number of rows, and a specific number of tubes within each row. For example, a chilled water coil might be 36 inch fin height and 8 rows deep. The coil has 24 tubes in each row, and multiplied by 8 rows, there is a total of 192 tubes within the coil. While you can try to feed any number of tubes, there are only a few combinations that will work.

    • Feeding 1 tube – you will be making 192 passes through the coil, which will essentially require a pump the size of your car to make that process work.
    • Feeding 2 tubes – equates to 96 passes, and your pressure drop will still be enormous.
    • Feeding 3 tubes – 64 passes, which is still too many.
    • Feeding 4 tubes – See above.
    • Feeding 5 tubes – Impossible as 5 does not divide evenly into 192 (passes).
    • Feeding 6 tubes – Still constitutes far too many passes, which again leads to additional pressure drop.
    • Feeding 7 tubes – Same rule for feeding 5 tubes.
    • Feeding 8 tubes –  Same rule for feeding 6 tubes.
    • Feeding 24 tubes – This feed consists of 8 passes, which is in the ballpark, and with a pressure drop you can live with.
    • Feeding 32 tubes – 32 tubes will see 6 passes. You might see a slight decrease in performance, but it’s off-set by a continuously better pressure drop.
  • Feeding 48 tubes – The magic combination, as 4 passes typically elicits the best performance and pressure drop simultaneously.

Rule #1: The number of tubes that you feed must divide evenly into the number of tubes in the chilled water coil.

Rule #2: The chilled water coil must give you an even number of passes so that the connections end up on the same end.

Rule #3: Based on the number of passes, you must be able to live with the resulting pressure drop. Acceptable tube velocity with water is between 2 and 6 ft. per second.

You’re bound to run into different terminologies depending on the manufacturer. More times than not, the different verbiage confuses more than it clarifies. However, understanding the basic tenets of chilled water coil circuiting will remove much of the perceived difficulty.  Check out Capital Coil’s Chilled Water Coils product page.

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Top 5 Reasons Commercial HVAC Coils Prematurely Fail

  • Commercial HVAC CoilsCoil Plugging: If you are not changing filters and/or your commercial HVAC coils are not properly cleaned in a timely manner, your coil will actually begin to act as a filter. When dirt builds up on the coil, that blockage prevents heat transfer and can cause an approximate 20% to 40% drop in performance. Dirt adds to the coil resistance and can be a primary cause for your coil to fail prematurely.
  • Vibration: When your HVAC coils are installed near a moving piece of equipment, vibration can occur and cause leaks. You can tell if vibration is the main cause if leaks are near the tube sheet and look like they are slicing through the tube. If/when that happens, the coils should be isolated from the rest of the system to prevent vibration from causing damage. One way to combat this is by oversizing the tubesheet holes, but many manufacturers will not do this. Condenser Coils are usually the most common victims of vibration.
  • Corrosive Environment: This applies to both the air in the environment and inside the tubes. For instance, if there is a corrosive element in the air, it will eat away at the copper tubes; whether you have 0.020” wall or 0.049” wall. This is very common in coastal areas where there may be salt in the air. To keep the costs down from going to a stainless steel or cupro-nickel coil, we usually suggest coating the HVAC coils. Coatings are almost always within your budget, and its application will only add about a week to the overall lead time. Steam condensate and untreated water can cause corrosion within the tubes of HVAC coils as well. If you have a steam coil that has failed before the one year warranty, there’s a great chance that corrosive agents are in the steam, and it’s eating away at the copper tubes.
  • Freeze-Ups: Most people think that when HVAC coils freeze, the water or condensate laying in the coil freezes into ice and it expands causing the tubes to bulge and eventually spring leaks. What really happens is that the coil will freeze in multiple areas simultaneously, and it’s the pressure between these areas that cause the tubes to swell and eventually burst. These are very easy to spot as the leaks will run the length of the tube rather than around the tube.  ALSO be very careful when considering “freeze-proof” coils!  If you remove 5-6 inches from the fin length to make the “freeze-proof” application fit, your coil’s performance will suffer considerably. 
  • System Design: You would be amazed to learn how many HVAC coils were never designed properly for their systems. If there is a design problem, replacing the coil will only waste time and money; while you have done nothing other than duplicate the previous problem. A little known fact in the replacement market is that a high percentage of all our projects are because the coils were built incorrectly or were never designed correctly in the first place. In some cases, owners attempt to improve the coil’s performance by adding additional rows. Most however do this without taking into account the air pressure drop or fluid pressure drop that comes with it.

When dealing with an HVAC coil manufacturer, try to partner up with one who will walk you through the engineering and explain it along the way. Capital Coil & Air has well over a decade of experience and can help you diagnose whatever problem that you are experiencing correctly the first time. We look forward to working with you on your next project!

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