"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."

AHHAC designs, installs and services commercial hot water plant across Melbourne — MAXA HWA2 reversible heat pumps that deliver heating, cooling and domestic hot water to 78 °C from a single low-GWP R290 system. For hotels, hospitals, aged care, schools, gyms and multi-residential strata, engineered from our Laverton North showroom.

ImmergasSimeThermaSkirt™Melbourne's larger buildings — hotels, hospitals, aged-care facilities, schools, gyms and strata towers — run on serious hot water and heating loads. The MAXA HWA2 industrial range answers all three at once: a single reversible heat pump / chiller that produces heating, comfort or process cooling, and domestic hot water up to 78 °C, using natural R290 refrigerant for the lowest global-warming impact in its output class. AHHAC specifies, installs and maintains this plant across Greater Melbourne from our Laverton North showroom.
Capacities run from 73 kW up to 192 kW of heating (and 60–152 kW of cooling) across eight frame sizes, and units cascade for larger sites. Paired with the right buffer and DHW tanks, one plant room can carry an entire building. See our full Melbourne hydronic heating service area, or talk to our commercial plumbing team about a whole-site solution.
The efficiency case for a reversible commercial heat pump is compelling in Melbourne's climate. Instead of separate gas boilers for hot water, a chiller for cooling and a boiler for space heating, a cascaded HWA2 system does all three — recovering heat between duties, running on electricity, and pairing with rooftop solar or a power-purchase agreement to cut operating cost hard. It's the same reversible principle used in residential hydronic heat pumps, scaled to plant-room duty. For the technology comparison that drives these decisions, see our guide on ducted vs hydronic heating.
Commercial hot water is a compliance-critical system: Legionella risk management, tempering, AS/NZS 3500 and 5601 certification, and BMS integration via BACnet or Modbus all have to be right. AHHAC delivers heat-loss and DHW-demand modelling, plant-room design, staged installation, commissioning records and ongoing service contracts — including the maintenance regime that keeps warranties valid. The most expensive commercial systems are the ones sized on a rule of thumb; our guide to mistakes to avoid explains why we model every job, and our overview of radiant floor cooling shows how the same plant can feed comfort cooling too.
Last updated 24 July 2026 · AHHAC
"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."