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Does Condensate Piping Need to Be Insulated? (Explained)

We include many appliances and devices to our house to make our livelihood easier and better suit our comforts. The environment outside is not often comforting to us, but we can alter the environment indoors according to our desires with the aid of air conditioners and furnaces. 

Condensate piping is one such component that allows these appliances to perform well. The abstract below will discuss the configurations of the condensate piping.

Does condensate piping need to be insulated? 

Condensate pipings of A/C or furnace do not need to be insulated according to the current U.S. Energy Code. If your condensate line does not have a leak but you notice exterior condensate forming – it may end up damaging the pipe, so it would be a good practice to insulate the condensate piping.

Condensate is the water produced by air conditioners or furnaces due to rapid heating and cooling of the vapor in the system. This condensate does not have any use and thus needs to be removed from the system and disposed of. 

The condensate water is usually sent to the pan mounted under or built within the system. From there, the condensate is removed by either piping or by the use of condensate pumps – depending on your appliance’s model and age.

The condensate drain line from the a/c or furnace is a line that connects the condensate exhaust line to the drainage to provide a sealed and clear pathway for the condensate to be removed from the system. 

These condensate lines are usually made with PVC or stainless steel pipes to be resistant from corrosion, rust or other deterioration that might be influenced by the moisture from the condensate passing through. 

The locations of these units are usually on the attics or similar secluded places with two condensate lines: one primary and a secondary, running from them. 

Primary condensate piping: 

The primary condensate piping comes directly off the coil and is connected to your home’s plumbing or drainage lines. 

Typically, a primary condensate piping would not require insulation – however, if you notice that your pipe is having exterior condensate deposits and your piping is not resistant to moisture, then it is necessary to insulate the line.

PVC condensate piping: 

In the case of PVC condensate piping, the case is a bit different. 

Since the condensate flowing through the piping has a low temperature that is down to the dew point temperature, it can cause the temperature of the pipe to be significantly lowered to the dew point temperature as well. 

This would cause the vapor on the exterior of the pipe to condense and deposit on the pipe – since PVC condensate piping works is resistant to moisture, additional insulation will not be necessary. 

What is the plumbing code for condensate drain insulation?

Building and Mechanical codes do not need you to install insulation on A/C condensate drain lines according to the U.S. Energy Code. Therefore, it is upon your personal preference whether you would install insulation on your condensate drain lines according to your needs. 

However, there are some notable exceptions in the plumbing code that you need to keep in mind.

N1103.3: Mechanical System Piping Insulation states your condensate piping that is capable of transferring fluids that is within the temperature range above 105°F and below 55°F must have an insulation to a minimum of R-3.

Energy code: Section 503.2.8 Piping insulation states that all the pipes that are used as a part of your heating or cooling systems need to be thermally insulated.

Apart from the standard codes, all the factory-installed piping used in the a/c or furnace needs to be rated within the guidelines of the U.S. energy code.

What should be condensate piping insulation thickness?

Other than some cases, there is no general guideline for the thickness requirement of the insulation used in condensate piping. Despite that, if you decide to install insulation for your condensate piping, make sure that its thickness is at least 1 inches. 

This configuration will provide good insulation while minimizing cost as well. 

Another factor that determines your insulation thickness is the thickness of the piping itself, if the pipe is 3 inches or less, the insulation has to be 1 inches thick. For pipes 8 inches and above – the insulation should be within 1½ – 2 inches thick. 

This is to ensure that no exterior condensate builds on the pipes as the cold condensate passes through the piping which is located in a humid environment. 

Insulation is necessary because these exterior condensates could encourage mold growth if left unchecked and lead to hygiene issues.

Why is condensate piping insulated?

There are several notable reasons why the condensate pipe is insulated, few of the key factors have been described in detail below:

To prevent formation of external condensate:

Humidity has been a critical factor in determining the longevity of pipes and joints, specially in case of metallic pipes. 

Since metallic pipes are still in use and also commonly used in many households, formation of external condensate can do considerable damage to the pipeline such as corrosion or weakening. 

To combat this issue, insulations are used to prevent the pipings from coming in contact with the humid air – thus preventing the external condensate formation.

Maintaining proper hygiene:

If the piping is installed in a hot and humid space, there will be faster formation of the external condensate due to the rapid condensation of the moisture. This moisture, along with the warm temperature gives rise to the perfect condition for mold growth. 

And in a short amount of time, the mold could cover the entire area and create health and hygiene issues.

For compliance with the U.S. Energy Code:

Although many pipings do not require the installation of insulation, there are many condensate pipings that exceed the usual case. In situations where the piping carries fluid with a temperature above 105°F or below 55°F must have an insulating layer coating the pipeline.

How do you insulate a condensate line?

Insulating your condensate line is a straightforward process if done right, the procedure below details how you can insulate your condensate line properly:

Use a weatherproof material to insulate the condensate line:

First, you need to choose a proper weatherproof insulating material of the correct thickness according to your pipe’s thickness. Next, take measurements of your pipe sections between the joints and note them down. 

Cut your insulating material according to the measurements taken to have a piece of insulation for each pipe. 

When done, wrap the pipes with the insulating material to ensure complete enclosure of the pipes.

Seal the joints properly:

After that, make sure you do not leave the joints between the piping exposed – apply an appropriate amount of insulating material to each of the joints until they are touching the insulation from the piping from all sides. 

Wrap heat tape or UV protection tape over the insulation:

To seal off the insulation and provide an additional layer of protection, you should wrap the insulation with heat tape or UV protection tape to tightly seal the insulation as well as give an additional layer of insulation to the piping as well. 

What type of pipe is used for condensate?

The material used for condensate pipes needs to be durable and resistant to moisture and chemicals since they will be installed for long term use

Condensate pipe lines usually carry water but also contain carbonic acid which is corrosive to metals – therefore using metallic piping would not be suitable or durable for long term use. 

However, stainless steel is a metallic alloy that can withstand corrosive strikes much better and have a longer durability – but they are not very cost effective, thus an all stainless steel condensate drain line may not be viable.

However, there is another alternative to this material that has a good durability, resistance to moisture and chemical pounces. PVC piping has been in use for over 70 years in various types of piping. 

The PVC pipes are also within the acceptance range of all the plumbing codes for use in condensate drain lines – which makes it an excellent choice of element for use.

Final Thoughts

According to the current U.S. Energy Code, condensate pipe from an A/C or furnace does not need to be insulated. If your condensate line does not have a leak but you find outside condensate forming, it may end up damaging the pipe, so it is a good practice to insulate the condensate pipes.