Guidelines For Air Velocities

The height, length and resulting air velocities greatly figure in everything in determining the size and performance of a coil. Step # 1 in determining the size and performance of a coil is dependent upon understanding face & air velocities of air across the coil. Whether you use CCA’s coil selection program to help size the coil, or you are replacing an existing coil; the height, length and resulting velocity determine everything.

Hot Water Booster Coils

air velocities

Every coil has a specific, optimum velocity, so you want to make sure you are within 30% (+ or -) of that number. For example, booster coils have an optimum velocity of 800 ft/minute. That means that you can drop your velocity to 600 ft/minute, or conversely, increase the velocity to 1,000 ft/minute. The duct velocities are almost always higher, which means that you will need to transition to a larger coil. Try to get to as close to 800 ft/minute as possible, while sizing your coil to make the transition as easy as possible. Everything with coils is a balancing act.

Hot Water & Steam Coils

Like booster coils, hot water and steam coils should also have face velocities at approximately 800 ft./minute. Both steam & hot water coils have only sensible heating, which is why their face velocities can be the same. Face velocities ultimately control the coil’s cost, so 800 ft./minute really is a heating coil’s “sweet spot”.

If you are purchasing an air handler unit, oftentimes the heating coil is smaller than the cooling coil because the face velocities on heating coils can exceed those of cooling coils. Due to water carry-over, cooling coils cannot exceed 550 ft/minute, while heating coils only deal with sensible heat.

Chilled Water & DX Coils

Due to the limited face velocities of cooling coils, your choices are more limited. With cooling coils, your face velocity must be somewhere between 500 ft./minute-550 ft./minute. Remember that when dealing with cooling coils, you are dealing with both sensible and latent cooling, so the coil is wet. When you exceed 550 ft./minute, water carry-over occurs past the drain pans.

If you are purchasing an air handler unit, you probably will not have worry about the coil’s face velocity as most coils come pre-sized at the acceptable face velocities. Fan coils also come pre-sized with the correct CFM’s. However, if you are replacing an existing cooling coil, the face velocity must remain at or below 550 ft/minute!!

 Air Stratification Across The Coil

Air does not travel equally across the face of a coil. If you were to divide a coil into (9) equal sections, like a tic-tac-toe board, you would see a high percentage of air travelling through the center square, rather than the corner squares. In a perfect air flow scheme, 11% of the air would travel through each of the 9 squares, but that is not what happens. Because more air travels through the center of the coil, you want to avoid putting a fan too near the coil. Due to central air flows, most systems are draw-thru, rather than blow-thru. This is also why you want to avoid installing your coil near any 90 degree angles/turns in the ductwork. Avoid any situations that contribute more than the “natural” air stratification to help ensure your coil is at maximum efficiency.

In some situations involving cooling coils, you will have water carry-over even when the coil is sized correctly. How can this happen? Think about the tic-tac-toe board again. Air velocities are exceeding 700 ft./minute in the coil’s center, while the corners are around 300 ft./minute. This cannot and will not work.

Coils do not have any moving parts. They simply react to the air across the outside of the coil and whatever is running through the inside of the coil. Coils are 100% a function of your entire system, as well as the installation in general.

Capital Coil & Air is here to help with any coil selections that will help avoid costly missteps that lead to wasted time and money. Call us on your next project, we greatly look forward to working with you!

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How to make your HVAC OEM Replacement Coil Buying Process Easier??

Roughly 100% of HVAC OEM replacement coil shipments use some kind of trucking company or common carrier. There are occasions when the shipment is small enough to use UPS or FedEx, but the vast majority of HVAC shipments are sent by way of truck. Anyone who has frequently used freight companies has experienced damaged shipments and/or late arrivals. In our industry, these annoyances and inconveniences are typically written off as “the cost of doing business”. Think of the airline industry as an example. Our expectations have been reduced to point where we expect something to go wrong and are pleasantly surprised when the trip is smooth from start to finish.

Many folks might not know this, but even before the pandemic struck, the trucking industry in general had been experiencing a gross shortage of drivers throughout the country. Some estimates have put this shortage of drivers as high as 50,000 throughout the country.

So what does this shortage mean for the HVAC industry? Put simply, it translates into complications and confusion for all involved.

  • Longer delivery times. For example, a delivery that used to take (3) days is now (5-7).
  • One major reason for the longer delivery times is that trucks now have many more stops than in years past. There are also many instances of more trips through connecting terminals as well.
  • More time on the truck usually equates to both “visible” and “hidden” freight damage.
  • The shipments become harder to track, and with fewer people at the trucking companies doing more work, shipments can and will get lost entirely.

Because the freight process is at the very end of the OEM replacement coil buying cycle, Capital Coil & Air has developed some simple strategies for the entire buying process that should help in avoiding many of the annoyances listed above. We’ve also added a very useful “hint” to counter longer freight delivery times.

  • Getting a price, delivery & accurate proposal from your vendor: Capital Coil responds to every quote request quicker than any of our competitors, and we are always willing to put that claim to the test. A (2) day delay in receiving your quote is the same as a (2) day freight delay on the back end.
  • Receiving your submittal drawings in a timely fashion: You need to approve these drawings, so once again, how is a (2) day delay in receiving approval drawings any different than receiving your order (2) days late?
  • Quick-Ships: As you’ve probably experienced numerous times in the past and/or present, other coil manufacturers seem to be consistently shutting down their quick-ship programs with little to zero notice for the customer. Why is this? Many manufacturers take on a glut of OEM replacement coil 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.

Capital Coil NEVER shuts down our quick-ship programs, and we emphasize NEVER! Over the last (2) years, CCA has hit approximately 99% of all quick-ship orders.

  • Crating equipment to minimize freight damage.OEM Replacement Coil
  • Shipping on time: Simply put, we consistently ship when we say we’re going to ship.
  • Select a freight carrier that delivers to your area without interlining or stopping at several terminals: This is when freight damage is most likely to occur!
  • Pay the carrier fee for a guaranteed delivery date: Although seemingly not well-known, most carriers offer a guaranteed delivery date for a fee of $50-$100. Paying the fee will ensure that your order is now a “priority”, and most freight companies schedule deliveries based on these “priorities” first. If both your order and delivery are critical and time-sensitive, Capital Coil can help you with exploring these delivery options.

Capital Coil & Air will work with you throughout the entire buying and shipping process because you as the customer, deserve to work with a hands on manufacturer that will not turn its back on you once the order has been placed. Please give Capital Coil a try on your next project!

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Four Things To Know When Buying Replacement Coils

While building numerous types of coils for various customers over the years, we’ve discovered the four main things that you need when replacing HVAC coils. We’ve found that most customers are searching for many of the same things, and also share many of the same priorities. Based on numerous conversations with our customers, we’ve compiled a list of the primary factors that you need to consider when purchasing an HVAC coil.

  • Marketing and advertising experts’ claim that a person needs to see and/or hear something an average of 3-5 times for the brain to really absorb the message. And so, in light of that claim, think DELIVERY, DELIVERY, DELIVERY, and DELIVERY! Every coil job has a degree of urgency to it, which is why the speed of delivery is so significant. Either you are beginning the process of replacing coils for a system that is shut Quick-Shipdown, or you are in the middle of a job and discover that you need coils to be delivered as soon as possible. In either scenario, you need a coil supplier that works on your schedule – not their own, independent timetable. Capital Coil’s Quick Ship Program allows the coils to be built on your timeline, not the manufacturer’s.
  • The coil MUST fit in the space allowed! You can purchase the highest quality coil ever manufactured, and if it does not fit, then you have nothing more than exquisitely manufactured scrap metal. So when measuring a coil, always remember that a little smaller is always better than a little bigger. There are 100 different ways to make a smaller coil work for you. On the flip-side, if a coil is too big, then you have no choice but to start over.
  • Performance matters! As with any purchase, it’s important to have an idea of what you are trying to accomplish. The simple act of duplicating a coil can sometimes work, but more often than not, additional performance information is needed. This is precisely where Capital Coil & Air can help. We’ll work with you to come up with a simulated performance schedule, even if you do not have all of the necessary information. Working in consultation with our clients tends to lead to an outcome that is acceptable to all parties.
  • Lastly and very importantly, there is cost. Everyone has budgetary constraints, and no one wants to break the bank paying for coils. However, buying a coil is often more than simply price alone. Taking into account required delivery times, sizing of the coils for the job, performance, and price, buying a coil can be a balancing act. While price should not be minimized, buying the cheapest coil is seldom the best coil for your job or application. The adage “you get what you pay for” certainly applies when it comes to coils. Capital Coil’s main goal is to help lessen your overall price, without sacrificing performance and quality.
 
 Performance options, size options, and shipment options will help you to spend your money in the most effective way possible. Capital Coil’s job is to give you the options and information that will allow you to make the best decision in your buying process. Your success is our success, so our goal is to have an on-going, consultative relationship that works for both parties. Call us on your next job, we’d love the chance to earn your business.
 

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Quick, Reliable & Uncommonly Fast

 Quick, Reliable & Uncommonly Fast

You have many choices when buying replacement coils and choosing a coil supplier. You could decide to diversify and work with numerous suppliers, based on a particular need. However, Capital Coil & Air can make your buying decisions a lot easier. We have been in the coil business for many years, and in this industry, we recognize what is important vs. what is irrelevant. That translates into us having good insight on what you need and how best to support you as a customer.

Quick

Coils today typically do not have much “preventative” maintenance done on them. Most everybody just waits until a coil fails and then worries about the problem at that time. And when coils inevitably fail, they fail during the times when you need them most; i.e. cooling coils failing in the summer and hot water coils breaking down in the winter. As a result, there is usually an urgency attached to most HVAC projects. Generally speaking, most jobs require some form of “quick-ship”. Capital Coil & Air gives you (4) different shipping options for all replacement coils. Our standard ship time is 3 – 4 weeks, but if you need your order faster, Capital Coil will accommodate that need. We do not want to have a “one and done” transaction. Capital Coil’s goal as a business is to have a customer base that we work with for 20 years, not 20 minutes. While we will do our best to give you the fairest price possible, you have to recognize that there is an additional premium associated with quick-shipments on replacement coils. However, you will never pay that premium if Capital Coil is late on manufacturing your order. We’ve built our business on quick-ships, and we hit 99% of all deadlines on orders the last two years. In other words, we rarely miss! We give you options, and you only pay for what you really need.

Reliability

Reliability encompasses so many things in the coil industry. For example, if you need a price today, and the sales rep takes (2) days to get back to you, that’s unacceptable and unreliable. If you require a drawing to help you design a job, and you are waiting for a week to have it returned? Again, not what Capital Coil considers reliable. If a coil supplier promises you a ship date and ships (2) weeks late? Once again, not reliable. Do any of the above issues sound familiar? It is easy to make extravagant promises, and companies do it all of the time. However, Capital Coil’s success rate on meeting and exceeding shipping schedules says more than any promise we can make. We believe in under-promising and over-delivering, not the reverse!

  • Capital Coil responds quickly to all inquiries for pricing, general information, and engineering assistance
  • Capital Coil manufactures high quality equipment in the U.S.A. and is AHRI Certified
  • Capital Coil’s years of experience will help you quickly pick the correct product for the correct application
  • Capital Coil provides accurate shipping dates, real-time tracking and common carrier information after your order has left our factory

We do all of the above to make everything in your life easier. Capital Coil holds itself to the highest standards for both reliability and customer service. In short, we want your experience with us to be professional and simple. Please call or email our sales department for any job – no matter how large or small. We greatly look forward to the opportunity to work with you 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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