Leaks in your plumbing system are never good. Some are just minor inconveniences, while others can cause your appliances and fixtures to malfunction. Some can even cause fire hazards. Your boiler’s condensate pipe leaking is not something to ignore. Read further to know what a condensate pipe is, how to deal with leaks in this pipe or the boiler, and a few tips on preventing it.
What is a condensate pipe?
A condensate pipe is a non-metal pipe that directs and drains the excess water from a condensing boiler to the wastewater system. It is typically the white, small, plastic pipe that comes out from the other side of the wall where the boiler is installed.
Before the 2000s, roughly speaking, most house boilers were of the type now called “non-condensing boilers.” They would heat the water and direct it through the system. The excess heat produced during the heating in these boilers, sometimes up to 30 percent, is then discharged through the flue. Today, modern-day boilers are designed to catch the excess heat and use it again. This makes the process much more efficient and saves considerable amounts of energy.
During capturing the flue heat, condensation happens due to the rapid decrease in the gas temperature. The resulting liquid is referred to as “condensate water.” A slightly acidic liquid discharged out of the boiler through the condensate pipe. The ideal route for a condensation pipe is through the internal wastewater system. However, many condensing boilers have their condensate pipe run externally through the wall and drained into the wastewater system.
The condensate pipe shouldn’t be made of metal. This is because the water running through this pipe has been condensed and has acidic properties. This pipe is also installed with a downward angle so that the gravity will help the discharge flow.
Why is my Boiler Condensate Pipe Leaking?
If you notice dripping around your condensate pipe, it’s good to know a few things before calling in a professional.
It has served its time.
Before looking for technical reasons why your condensate pipe is leaking, the cause might be the age of your system. As we said earlier, it is ideal that the condensed water is directed to the waste system internally. If your condensate pipe is run outside, just like every outside fixture, it will suffer more wear and tear over time. Being exposed to the elements like heat and cold will not only wear out your pipe sooner but can also freeze the water through the pipe and make a blockage. We will let you in on that soon.
The Condensate Trap is Blocked
The condensate trap is a U-shaped apparatus similar to the one used in the kitchen sink. It keeps condensed water in a boiler until it reaches a certain level before discharging it in bursts. Sometimes, debris can enter the condensate trap and form a blockage. If this trap is blocked, water will not be allowed to flow into the condensate pipe freely. This can put too much pressure behind the joints and make way for water to seep out.
Broken Heat Exchanger
As the name suggests, the heat exchanger passes heat through and increases the temperature of the incoming water. If the heat exchanger cracks, it will start letting boiling water into the condensate pipe directly. Since the condensate pipe is made of plastic, the continual flow of boiling water will cause the joints to leak and eventually break. In this case, the condensate pipe must be changed entirely.
It is essential to the longevity of every plumbing system that the joints are correctly connected. If inappropriate material is used while sealing the joints, especially those relating to a boiler, joints are likely to split, leak, or burst.
Frozen Condensate Pipe
If the condensate pipe of your boiler is directed outside, it will, at some point, be exposed to cold. If water is frozen inside or at the bottom where it exits the pipe, it will block the system. The blockage formed this way not only can cause leaks through the joints but stop the boiler from functioning altogether.
Some measures have been taken to help water flow through the condensate pipes without freezing. The boiler has a small container built into it to allow the water to accumulate before discharge. Instead of dripping, these small bursts of water will prevent freezing reasonably. On top of that, the correctly installed condensation pipe has a proper downward angle, so the water spends less time inside the tube.
To fix a frozen condensate pipe, heat some water and slowly pour it from the top along the line. Do it a few times if necessary. Running boiling water onto plastic pipes can damage the joints and seal, so go with warm water. After you’re done, double-check the joints and fittings since they might split when the water inside freezes. Use proper insulation to prevent the pipe from freezing again.
Make sure the condensed water directly drains into the wastewater system.
Although it might not count as an actual leak, the condensed water must drain adequately and not drip onto the floor. If the pipe is installed, the wastewater is directed and poured over the outside foot, and it will erode the ground. On top of that, wind can carry the drops away, and since the water is acidic, it will damage the surfaces around it.
Sometimes, the leaks can be coming from the boiler itself. Here are a few reasons:
High water pressure
When water is heated in your boiler, it expands. If your boiler’s water pressure is too high, it can build up and damage your boiler and the connecting pipes. When your boiler starts, keep an eye on the water pressure gauge rising. Make sure it doesn’t go far beyond the marked level. If the pressure is too high, try bleeding your radiators for some relief. If that doesn’t work, the problem can also be your pressure relief valve. If nothing works, don’t hesitate to seek a professional’s help.
Improperly sealed joints
As previously mentioned, hot and cold water are continually passing through your boiler joints. If they are not sealed correctly with the proper material, they will soon split and let water out.
How to avoid my boiler condensate pipe from leaking?
- Follow the Manufacturer’s Instructions when installing your boiler and pipes.
- The pipe must have the proper size. Water won’t flow through freely if the condensate pipe is too thin.
- The condensate pipe must be installed at a downward angle. (If the boiler is located below the drain -in the basement-a condensate pump is needed to direct the water to the drain).
- Condensate pipes must be non-metal to avoid corrosion from acidic water.
Generally speaking, fixing or replacing things that work with electricity and gas are not good DIY projects. Unless you have adequate previous experience, we strongly recommend seeking a professional’s help for a safe fix.