Installing a solar pool heating system not only extends your swimming season, but can also add value to your home. However, if incorrectly installed the integrity of your new asset can be jeopardised, especially during system drain down.

vacrel pipe crush
Properly installed, a solar pool heating system should freely drain back to the pool without subjecting the solar system to any negative pressure each and every time the solar pump is switched off. This drain down results in outgoing water being replaced with incoming air; any restriction to this incoming air will create a vacuum within the solar system that has the potential to irreparably damage systems components.

It may come as a surprise to some people as to the degree of damage this vacuum may present, as you can see in the image above, the negative pressure can be so intense that it will crush a PVC pressure pipe. The Boss VacRel® Vacuum Relief Valve has been specifically engineered to open at an extremely low negative pressure (-6.8 mbar) to allow the air to enter the system unimpeded thus protecting the systems components from crushing, thus eliminating internal splits and leaks.


The Boss Solars VacRel® is:
  • Australian Made – Reliable Pressure Relief for your System
  • Manufactured from only premium grade materials: German BASF Luran®S mouldings (no cheap ABS substitutes)
  • A top of the range USA Vernay Viton umbrella valve
  • Nitrile rubber O-ring seal
  • Quality 316 Stainless Steel triple pass filter mesh
  • A high quality valve designed to suit the harsh Australian conditions
  • Beware of cheap imitations – Look for the VacRel® Trademark
  • Manufactured to suit 40mm UPVC fitting
vacrel article



Boss Solar does not believe in compromising the components performance by taking the easy or cheap road. Don’t compromise your system with cheap substitutes.

Boss is committed to providing premium products you can rely on, ask your Pool Professional to install the best, a Boss Solar VacRel®.