Condensate pipe
- Condensate pipe overview. Water vapour from the combustion process is channelled through the boiler until so much heat is drawn out of it, it condenses back into water.
- Construction. The condensate pipe must be plastic – usually solvent-weld fittings – and at least 22 mm in diameter.
- Faults. ...
How does condensate return to a boiler?
- Backpressure from lift created by an elevated collection tank
- Piping friction caused by transporting condensate over distance
- Pressurized Collection Tank or Flash Vessel
- Condensate directly returned to the boiler
What is the condensate line and its function?
Unclogging Your Condensate Drainage Lines
- Using the breaker or thermostat, turn off the power of the HVAC system.
- Find the condensation pan, usually under the unit, if your air handlers are indoors.
- Standing water in the drain pan indicates that you have clogged the condensate line. ...
- Look for a PVC pipe usually located outside with a PVC cover. ...
What is a condensate drain pipe?
Condensate drain pipework will slope towards the drain discharge point. When using a spirit level a turn of the bubble shall be adequate to identify the correct slope. At discharge points either directly above the funnel drain on the grey water system or sump pit, the condensate discharge shall be visible, i.e. drain line and funnel will not be ...
What is a condensate P trap?
What is a condensate P trap? The primary purpose of the P-trap in a plumbing system is to form an isolation seal between that system and the sanitary sewer, thereby preventing sewer gases and other contaminants from entering the building. The drain seal on the condensate drain line of a draw-through hvac system has an entirely different purpose.
What is a condensate pipe?
A condensate pipe carries condensation from your boiler to your outside drain. It's usually a white or grey plastic pipe that travels from your boiler through the wall directly outside where your boiler is located.
Which pipe is the condensate pipe?
The condensate pipe is usually a white PVC-U pipe, similar to one you may find on a washing machine or sink waste pipe which usually goes outside into a drain.
What does a condensate do?
Condensate units increase efficiency and can even reduce your utility costs. Since the steam that is returned to the boiler is already similar in temperature to the boiler water, less energy is necessary to reheat it – thus reducing your oil, gas, or electricity costs.
What is steam condensate piping?
Condensate piping is used to remove condensate from steam-heated vessels, ideally for recovery and re-use in boiler feedwater. When hot condensate under pressure is discharged from a steam trap into a low pressure system, the resultant pressure drop causes some of the condensate to flash into steam.
What does my condensate pipe look like?
Look under the boiler to see if there is a plastic pipe - It's usually white and around 20mm (about ¾”) wide. The pipe should run to the outside of your home and should always run into a drain. An example of a condensate pipe is shown below. The condensate pipe is the diagonal pipe running along the side of the house.
Does a condensate pipe have to go into a drain?
A condensing boiler will produce about 2 litres of condensate an hour at an average temperature of 30-40℃. This condensate needs to drain into your waste water outlet or to a drain via your condensate pipe.
Where does condensate line drain?
In newer homes, HVAC condensate drains are tied most often to bathroom drains. Common drain lines inside your home include in your bathrooms (sinks, shower or tub, toilet), kitchen (sink, water line to your freezer), laundry room, and water heater.
How do condensate lines work?
The line is an exit route for moisture collected by the evaporator coil as air passes over it. The coil removes humidity from the air and converts it into water. The water drains into the condensate drain pan, enters the drain line, travels down the drain pipe and is deposited outside near the AC's outdoor unit.
Does a combi boiler have a condensate pipe?
Most of the best combi boilers will have a specific error code to indicate a frozen condensate pipe, which will be displayed on the interface.
What is the difference between steam and condensate?
Condensate is the liquid formed when steam passes from the vapor to the liquid state. In a heating process, condensate is the result of steam transferring a portion of its heat energy, known as latent heat, to the product, line, or equipment being heated.
What size should a condensate pipe be?
Any external boiler condensate pipe must be a minimum internal diameter (ID) of 30mm, and insulated, using suitable waterproof and weatherproof insulation. Any internal condensate pipe should be a minimum of 19mm ID and upsized to 30mm ID minimum before passing through the building structure to outside.
Why condensate steam is recirculated to boiler?
At the end of a steam power cycle, the steam is condensed to water. A condensate pump moves the water through LP heaters back towards another pass-through deaerator and boiler. All centrifugal pumps have a minimum flow rate through to pump to avoid overheating and cavitation.
Can't find my condensate pipe?
Locate your condensate pipe, which runs from the bottom of your boiler. It's usually a white or grey plastic pipe that runs through the wall and outside the property for part of its length. Remove any insulation that is fitted to the pipe work. Hold a hot water bottle or microwavable heat pad around the pipe work.
How do I know if my condensate pipe is clogged?
Signs that your condensate trap is blocked can include a faint gurgling noise coming from your boiler, or an unusual sound coming from the flue outside your home. If the trap does need to be cleaned, your heating engineer will remove it, rinse it out thoroughly, refill it and then refit it.
Where does the AC condensate pipe go?
Every AC system has a condensate drain line (a white PVC pipe) that runs from your indoor air handler to the outside of your home. During normal operation, condensate is safely carried out of your home via the drain line. You'll usually find the drain line near the outdoor condenser unit.
Do combi boilers have a condensate pipe?
What is a condensate pipe? SInce 2005, it has been a UK requirement that all gas combination boilers use condensing technology to increase their efficiency. Condensing technology allows heat existing in the flue gasses to be captured and 'recycled' back into the heating system to heat the water inside the boiler.
What happens if there is no flash in a steam line?
However, a “no flash” situation can only occur if the condensate is significantly subcooled to a temperature less than the saturated water temperature associated with the recovery line pressure. If the amount of flash steam is large, the required piping size becomes almost identical to that of steam piping.
How is steam condensate discharged?
Condensate that is discharged from steam traps is handled in one of two ways. It is either drained out of the system to sewer, which can result in wasted heat energy and water, or it flows into piping to be transported elsewhere, ideally for recovery.
What is condensate recovery piping?
The design sizing of such piping requires significant specialization because condensate recovery piping collecting from steam traps must be designed for two-phase flow. The design should not be based on calculations for piping that transports only water because these are not valid for two-phase flow.
What is a two phase flow?
Two-phase flow refers to flow in which vapor such as steam (either flash steam, live steam, or a mix of both) flows through piping together with liquid condensate. Although flowing together, this does not necessarily mean that the liquid and vapor are flowing in distinct separate layers. The flow pattern within the piping can also be mixed, ...
What are the factors that affect condensate recovery?
Both of these may have the effect of increasing velocity, pressure drop, and system back pressure.
Why use flash tank?
There are multiple benefits to installing a flash tank. The flash steam can be used to supply low pressure equipment or be used for pre-heating, while the hot, non-flashing liquid condensate can be returned to the boiler where its heat is reused, increasing overall efficiency.
Can flash steam be used locally?
If the flash steam energy can be used locally, the system designer can weigh the relative benefits of either a) returning condensate to the boiler, using smaller size piping but requiring a pumping system, or b) using larger piping to return the condensate without a localized flash system.
What is the best material for a condensate pipeline?
The recommended material to use for a condensate system is stainless steel. Stainless steel greatly enhances the pipes’ ability to withstand the corrosive attack for a longer, more reliable operational life. However, understanding the cost limitations to an all stainless steel condensate system, other alternatives are available. If carbon steel piping is used for economical consideration, schedule 80 pipe is used because of the heavier wall thickness, which prolongs the life of the pipe in a corrosive environment.
How to recover condensate from boiler plant?
Remember these tips: Recover and return all possible condensate back to the boiler plant as hot as possible. Accept no component failure within three years of operation. Install components with maintenance in mind. Size condensate lines understanding the medium will be two phase flow. Utilize connections that minimize leaks. Understand the various pressures of condensate returns available in order to design the piping system with proper flow. Remember to allow for pressure gauge installations throughout the system. These inexpensive devices are a key aid in troubleshooting the steam and condensate system. Following these rules will help to ensure a reliable and long life span of the condensate system.
How fast can a condensate pipe be?
Condensate piping velocities (liquid only) must be lower than 7 feet per second.
What is a reasonable specification for a condensate system?
A reasonable specification for condensate system design is to provide a reliable and long operational life span of more than 20 years without a primary condensate system failure. Plant personnel must assume that the condensate system designs shall include reasonable maintenance and plant services. Forgoing a proactive maintenance plan will reduce the anticipated lifespan of the condensate system.
Why is condensate loss in boilers?
A typical reason for condensate loss in the system is due to condensate component failure.
What is the difference between hot water and condensate?
The key item to remember is that there are two major differences between condensate and hot water. Condensate lines will contain two phases, condensa te (liquid) and flash steam (gas.) Therefore, the correct size of a condensate line is somewhere between a hot water line and a steam line.
Where are condensate branch lines connected?
It is imperative that all condensate branch lines are connected into the top dead center of the main condensate header on a horizontal plane . This cannot be overstated and there is no exception to this rule. Improper condensate connections are listed below:
What is the ASME B31.1 power piping code?
It is recommended that piping be designed according to the ASME B31.1 Power Piping Code. 2. Materials. Condensate piping systems are vulnerable to carbonic acid corrosion. For this reason, stainless steel is recommended to prolong system life but cost implications might preclude this as a material of construction.
Why is flash steam so high?
Flash steam can cause very high velocities if the return line is not sized correctly, causing back pressure in the system and reducing steam trap performance .
What happens when condensate is discharged from a steam trap?
When hot condensate under pressure is discharged from a steam trap into a low pressure system, the resultant pressure drop causes some of the condensate to flash into steam. Consequently, the design of condensate piping systems is not as straightforward as that for transporting water, as it must accommodate “two phase” flow.
Why do you need to design and install condensate piping?
All components of a condensate piping system must be designed and installed for ease of maintenance. Lack of regular maintenance will lead to poor system performance, and inevitably, structural failure.
Can condensate pipes be welded?
Threaded connections don’t have the capacity to withstand this thermal cycling and are also a prime target for acid corrosion. Ideally, pipes should be welded or tube connectors employed to minimize leaks.
What happens if my air conditioner is not level?
If the wall mounted air conditioner is not level, condensate may collect in its internal drain pan but may overflow the (relatively shallow) condensate pan edges before reaching the condensate drain opening.
What happens if there is no overflow pan under the air handler?
If there is no overflow pan under the air handler, especially in units installed on upper building floors or in an attic, when the condensate drain clogs or the condensate pump fails you can expect to have leaks into the building and possibly costly mold or water damage.
What is an auxiliary drain pan?
1. An auxiliary drain pan with a separate drain shall be provided under the coils on which condensation will occur. The auxiliary pan drain shall discharge to a conspicuous point of disposal to alert occupants in the event of a stoppage of the primary drain.
Why does my heat pump overflow?
One of the most common causes of air conditioning or heat pump condensate leakage and overflow is a clogged condensate drain line trap. And if the secondary or emergency condensate handling system is absent or defective, the result can be costly leak damage to the equipment or to the building.
How to tell if condensate drip pan is leaking?
Check the condensate drip pan and at bottom of the "A frame" cooling coil, indicating that the drain may need cleaning and more important, indicating that the condensate is leaking out of the equipment or drains and not being carried to an acceptable disposal point.
What are the components of a condensate disposal system?
Components of the condensate disposal system shall be cast iron, galvanized steel, copper, cross-linked polyethylene, polybutylene, polyethylene, ABS, CPVC or PVC pipe or tubing. All components shall be selected for the pressure and temperature rating of the installation.
Is condensate drain line a part of air conditioning service?
The condensate drain line, trap, and evidence of blockage, leaks, overflow, or improper piping should be part of annual air conditioning system service, or should be performed immediately if there is evidence of a condensate spill or leak. .
What is the condensate line in an HVAC system?
This humidity eventually turns into condensation that must have somewhere to go. Enter the condensate line, which essentially functions as a drain line . Condensate lines are typically made of plastic (commonly PVC) or sometimes metal, although plastic is prefered.
What is a condensate line?
The condensate line is one of the most important components of your HVAC system. Your condensate line, also known as a “condensate drain line” or “condensate drain” does several jobs, but none are more critical to the functionality of your appliance than draining excess moisture outside of your home. Condensate lines are of particular importance ...
Why is condensate line important?
Why is your condensate line important? Your condensate line keeps moisture from building up inside your home and, specifically, inside your HVAC unit. Moisture is the enemy of any functioning appliance as it can lead to mildew, mold spores and corrosion.
What is the condensate pan on a furnace?
Although some HVAC units and furnaces have what’s called a “condensate pan” beneath them to catch drips, most modern units entrust the condensate line with effectively funneling all residual water outdoors where it can evaporate into the air.
How does a condensate line work?
It connects directly to the HVAC unit and leads outdoors, often through an exterior wall. Its job is to efficiently funnel condensation away from your HVAC unit . Sometimes a small pump is attached to the HVAC system to expedite the process, but most condensate lines utilize gravity.
How to tell if condensate line is clogged?
The best indication that your condensate line is clogged is an inefficient HVAC system. Most new AC units have automatic shut-off technology that initiates when water backs up. If your AC is constantly turning on and off without significantly cooling your home, you may have a problem. Otherwise, it can be tricky to tell when a line is clogged ...
