Flypass Valves: An Effective Solution In Plumbing
Flypass Valves are relatively new to the HVAC industry – you may not have come across them in your previous projects.
They are a multifunctional valve assembly that covers all functions required for installation, commissioning, and operations of Fan Coil Units in Hydronic systems.
What is a Flypass Valve?
A Flypass Valve is a pre-assembled valve assembly consisting of several valves and fittings for installing on to Fan Coil Units.
As we all know, wherever there is a coil, there is a requirement to control the amount of water travelling across that coil.
The Flypass is a straightforward method both in terms of initial installation and measuring, flushing and isolation of water for each coil.
Flypass valves have the following features:
- Three-way balls which can be turned by 180° to allow various positions – these are displayed by the shape of the handle and the imprinted flow directions
- Flat sealing connections to the appliance side, allowing for the connection to components without intermediate pieces
- Optional conversion to bypass operation
- Extended handles, allowing for insulation of the fitting
- One fill-and-drain ball valve supplied as an extra – the Flypass valve also has the connection facility for an additional fill-and-drain ball valve
- Differential pressure measurement across the appliance side (made possible through the use of the additional fill-and-drain ball valve)
- Different products for direct connection to the connection fitting are available

How does a Flypass Valve work?
A Flypass Valve is used for the connection of fan coil units (FCUs), chilled ceiling modules, induction air systems, and cooling and heating zones to the pipework of central heating and cooling systems with closed circuits.
You can choose the direction of the flow thus allowing isolation, draining, flushing, and measuring.
The connection fitting can be installed in a range of various positions, including vertical, oblique, or horizontal.
Flypass Valves vs The Traditional Plumbing Approach
The traditional plumbing approach involves buying separate parts and installing them each individually onsite. Plumbers have always done it this way and are slow to experiment with alternative methods.
The truth is the labour hours in doing this within construction site conditions will always be longer than assembling a unit off site within a controlled environment.
The Flypass Valve is applying the ‘Prefab’ approach to control valve installation. This approach is becoming widely accepted across the industry for many HVAC related products.
Traditional forms of plumbing can be tedious with expensive labour costs attached, but our Flypass Valve offers a more cost and time-effective solution than the standard industry approach.
Flypass Valve Benefits
- Reduces installation time on site
- Reduces labour costs on your project
- Reduces commissioning time
- Allows for isolation and local draining
- Meets BISRA flush velocities
- Reduces ongoing occupant temperatures complaints
When is a Flypass Valve an appropriate addition to your system?
A Flypass Valve is beneficial in any high-rise, commercial or residential building, including hospitals, convenience stores and shopping centres.
Using a Flypass Valve provides you with the most effective method when it comes to installing central heating and cooling systems for your business.
Masterflow’s Flypass Valves
Our Oventrop Flypass Valves are top quality. Oventrop is known for its innovation with control valve technology.
As the official Australian distributor of the Oventrop range, Masterflow is well placed to service your project.
You can download an overview of all Flypass Valve pipe functions here.
Got more questions? Get in touch today.