One common question that HVAC technicians often encounter is whether a wall-mounted mini-split system requires a condensate trap on the condensate line. This question typically arises from technicians who are accustomed to installing ducted air handlers that do require a trap. In this article, we will explore the need for a condensate trap in both ductless and ducted air handler systems.
First, let’s understand the purpose of a condensate line. The condensate line allows for the drainage of any condensate water that is produced by the air handler. In both ductless and ducted systems, the air handler removes humidity from the air as it passes over a low-temperature coil. The moisture in the air condenses on the coil, and the resulting water needs to be drained away.
In a ducted air handler system, a trap is necessary to ensure proper drainage. Without a trap, the water will not be able to drain effectively. This is because the air being pulled into the pan will prevent the water from flowing out unless there is water in the trap to create a barrier. A trap in a ducted system helps to block the air from getting sucked into the system, allowing the water to trickle out.
However, in a wall-mounted mini-split system, a condensate trap is not required. The reason for this is that these units are ductless, meaning they do not have a duct system to deal with. As a result, there is no need to create a barrier to prevent air from entering the system. The condensate line in a wall-mounted mini-split system can simply be pitched downwards and allowed to drain without the need for a trap.
To further illustrate this point, let’s compare the velocity of the condensate line in both types of systems. In a ducted air handler system, the velocity of the condensate line can be measured using a rotating vein anemometer. This measurement will show a significant velocity, indicating the need for a trap to prevent water overflow.
On the other hand, when measuring the velocity of the condensate line in a wall-mounted mini-split system, the rotating vein anemometer will show zero feet per minute. This is because there is no static pressure from a duct system, and therefore, no need for a trap to block the air.
While it is not necessary to have a trap in a wall-mounted mini-split system, it is important to ensure that the location where the condensate is dripping is safe and will not cause any water damage. If there are concerns about insects or other pests, a dry trap can be added, but it is important to note that adding any additional components to the system can lead to potential clogs and problems in the future.
In conclusion, a wall-mounted mini-split system does not require a condensate trap on the condensate line. Unlike ducted air handler systems, these units are ductless and do not have the same static pressure that necessitates a trap. However, it is crucial to ensure that the condensate is dripping in a safe location to avoid any water damage.