World News

Industry news and insights from Europe and around the World

UK News

Latest news and developments in the United Kingdom

Products

Keep up-to-date with the latest new products and technology

Features

General articles, applications and industry analysis

Five reasons for coil failure

Capital-Coil

Matt-JacobsMatt Jacobs, president of US coil manufacturer Capital Coil & Air has come up with his top five reasons for coil failure. 

5. Coil plugging

If filters are not changed or your HVAC coils cleaned properly in a timely manner, your coil will actually act as a filter. When dirt builds up on the coil, it will prevent heat transfer and can cause a 20% to 40% drop in performance. Dirt adds to the coil resistance and will absolutely cause your coil to fail prematurely.

4. Vibration

When your HVAC coils are installed near a moving piece of equipment, vibration can occur and cause leaks. The area where these leaks occur is very important and will clue you in to if the problem is vibration. If they are near the tube sheet and look like they are slicing through the tube, 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 tube sheet holes, but many manufacturers will not do this. Condenser coils are usually the most common victims of vibration.

3. Corrosive environment

This applies to both the air in the environment and inside the tubes. For instance, if there is something in the air that is corrosive, it will eat away at the copper tubes whether you have 0.020in wall or 0.049in wall. This is very common in 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. 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 corrosive agents are in the steam and it’s eating away at the copper tubes.

2. 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 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.  And be very careful when considering “freeze proof” coils.  If you remove 5-6in from the fin length to make it fit, the coil performance will suffer considerably.

1. System design

You would be amazed how many HVAC coils were never properly designed for their systems. If there was a problem with design, replacing the coil will only duplicate the problem. A high percentage of all our projects were because the HVAC coils were built incorrectly or was never designed right in the first place. Sometimes, owners want to improve performance by adding a couple rows, but don’t consider the air pressure drop or fluid pressure drop that comes with it.

Capital Coil & Air

Latest News

18th March 2024

Joint venture adopts Epta brand

ITALY: All activities under the recently announced Epta and Viessmann Refrigeration joint venture are to operate under the Epta brand.
18th March 2024

Low carbon heat briefing

UK: The SIRACH network is hosting a half-day briefing at London’s iconic Shard to share the findings of the Lot-Net project. 
18th March 2024

UK heat pump uptake too slow

UK: The UK must achieve an eleven-fold increase in heat pump installations if it is to hit government targets of 600,000 heat pumps installed per year by 2028.
18th March 2024

Refrigeration’s star engineer Forbes Pearson dies

UK: Stephen Forbes Pearson, co-founder of Star Refrigeration and one of the world's greatest refrigeration engineers, has died at the age of 92.
17th March 2024

132 Güntner dry coolers for Red Sea project

SAUDI ARABIA: German manufacturer Güntner has supplied 132 dry coolers, each with 18 fans, to a 32,500TR district cooling project in Saudi Arabia.
17th March 2024

NZ professor brings fridge workshops to UK

UK: Don Cleland, a professor of process engineering at Massey University in New Zealand, is hosting a series of refrigeration workshops in London this summer.