How to SAFELY Flush HVAC Pipework

2 min read

There’s a complaint we often get – “Your pumps had faulty seals from the beginning”.

We understand our pumps get full of dirt, waste and welding dross while being installed. The common serviceman’s solution is to flush the system using the installed service pumps, but these pumps are designed to move clean liquids only. Therefore, all waste inside the pumps and pipework gets flushed through the system and out, leaving your system clean but your pump damaged.

Shortly after installation, we tend to get calls about our faulty seals, wear rings and impeller faces.

We know for a fact that this isn’t the pump’s problem. All of our products are quality tested before dispatch, and nothing goes out to our customers without first being ticked off by our engineers. Over 25 years of experience in the HVAC industry allows us to make informed engineering decisions and create the best solution for you.


IF flushing is done correctly, our pumps should run perfectly. 

Here’s how to do it without causing problems:

Get a flushing rig.

These are excellent for cleaning out your system without compromising the quality of your service pumps.

Our flushing rig includes a 4kW-45kW motor pump, VSD fitted and with a complete power display.

There’s a filter socket enclosed in a tank on the discharge side for smaller models, and a filter socket in a Y-strainer for the larger models. Flexible hose connections can be fitted with camlocks on smaller models, and reinforced HD rubber hosing with crimped ends on the larger models.

They also come with quality balancing valves and instrumentation to measure velocities needed to clean the pipework. All of this fits on a wheeled trolley that fits through your average doorway.


What if I don’t flush the system?

DON’T do this.

We’ve witnessed too many instances of foreign matter damaging installed equipment. This ranges from obvious mill scale to seemingly harmless suspended particles. So yes, flushing is a necessary part of commissioning to ensure the best possible health of your HVAC system.

Even after commissioning, external influences such as incompatible or excessive chemical treatment additives added to the system will eventually impact on the installed rotating equipment throughout the circuit. This means flushing should be done more often than just during the pre-commissioning stage.


The Next Step – Getting Your Flushing Rig

You might be thinking: We’re only going to use this piece of equipment every few months! Why would we buy one?

So we’re saying: You don’t have to. We’ve got flushing rigs ready for purchase OR lease.

Rent a flushing rig every time you’re installing service pumps. It’ll make sure your pumps run correctly from day 1, and it’ll save you from build-up issues like cavitation.

Tell us about your job, and we’ll get right back to you with sizing for your flushing rig.


Got more questions? Talk to us here. Or if you’d prefer to hear our voices, call us at 02 9748 2022.