Multilayer PEX-AL-PEX pipe, press fittings, manifolds and the complete hydronic pipework system. AHHAC supplies the Italian Aquatechnik Group plumbing and heating range.
The best hydronic pipe for most Australian installs is multilayer PEX-AL-PEX: an aluminium core between PEX layers that blocks oxygen, holds its bent shape and expands far less than plain PEX, joined with flame-free press-fit fittings. Correctly installed, the pipework is designed to last 30+ years. AHHAC supplies and installs the Italian Aquatechnik multilayer range with Safety-Pol and Fluxo press fittings, and pressure-tests every circuit before handover.
Reviewed by the AHHAC Technical Team — licensed plumbers & hydronic engineers, NSW Lic 262528C.How we write & review
The pipework is the circulatory system of a hydronic install — and the quality of the pipe and fittings determines whether the system stays leak-free for 30+ years or becomes a maintenance headache. AHHAC specifies premium multilayer pipe and press-fit fittings on every system.
Our preferred pipework supplier is Aquatechnik Group s.p.a. — Italian-engineered multilayer (PEX-AL-PEX) pipe and the Safety-Pol / Fluxo press-fit fitting systems. Multilayer pipe combines the flexibility of PEX with the oxygen-barrier and shape-retention of an aluminium core, making it ideal for hydronic heating, cooling and potable water.
Multilayer PEX-AL-PEX won't corrode, scale or allow oxygen ingress (which protects steel components like radiators and pumps from rusting). The aluminium layer means the pipe holds its bent shape and expands far less than plain PEX. Press-fit fittings make a permanent, tested joint in seconds with no heat, flame or solvent — faster to install and impossible to under-tighten. AHHAC pressure-tests every circuit before handover.
Once the walls are lined and the slab is poured, the pipework is the one part of a hydronic system you cannot easily change. It is designed to last 30+ years, so we treat it as the part that has to be right first time.
Size the pipe to the heat source. A heat pump moves more water at a smaller temperature difference than a gas boiler does. Pipe sized for an old boiler can be too small for a heat pump, which shows up as noisy flow, a pump working flat out and rooms that never quite reach temperature. On a retrofit we check every existing main before reusing it, and on new work we size each run to its design flow rather than using one diameter throughout.
Before any wall is closed or slab poured, every circuit is filled and pressure-tested, and we photograph the pipe runs for your handover file. That record makes later renovations far safer.
Oxygen-barrier multilayer protects the steel parts of the system, but it works best alongside a proper hydronic water treatment dose, and it needs well-set hydronic valves and manifolds to deliver even heat. If you are adding hydronic to an existing home, our guide to retrofitting hydronic heating explains how we route pipe with minimal disruption.
Written from on-site experience by the AHHAC Technical Team.
AHHAC's in-house design and service team — licensed plumbers and hydronic engineers (Lic 262528C) who have designed and installed 2,400+ hydronic heating, cooling and hot water systems across Australia since 1998.
We only specify equipment after a heat-loss and system-compatibility check, then supply, install and commission it with our own licensed plumbers to AS/NZS 3500 (plumbing) and AS/NZS 5601 (gas), register the manufacturer warranty and service it for the life of the system.
"AHHAC delivered our 22-zone underfloor system on time, on budget and to spec. The crew were tidy, the documentation was thorough, and the commissioning was textbook."
"We've worked with AHHAC for 17 years. They've installed and serviced our hot water plant across three commercial buildings — and they pick up the phone on weekends."
"Three mobs quoted us; AHHAC's design was the only one based on a proper heat-loss calculation. The system runs beautifully — the others would've been oversized and expensive."