Hydronic heating Camberwell

AHHAC designs and installs hydronic heating in Camberwell and across Boroondara, from Canterbury and Surrey Hills to Glen Iris, Balwyn and Ashburton. A lot of the work here is not a brand-new system. Many Camberwell homes already have gas hydronic heating, with a boiler in a cupboard or on an outside wall and panel radiators through the house, and many of those boilers are now well into their second decade. Owners want to know whether to replace like for like, switch to an all-electric heat pump, or do something in between. We answer that from a room-by-room heat-loss calculation, with a fixed-fee design and quote back within 24 hours of the site visit, as part of our wider hydronic heating Melbourne service.

Camberwell's housing: Edwardian, inter-war and Californian bungalow

Three eras of housing dominate Camberwell's streets, and each one shapes the heating design. Edwardian and Federation villas have high ceilings, double-hung windows, ornate cornices and suspended timber floors, often with fireplaces that were never meant to heat a whole house. Inter-war homes from the 1920s and 1930s, including the many Californian bungalows with their deep verandahs and low-pitched roofs, are usually brick or weatherboard on timber stumps with good subfloor access. Then there are the post-war homes, the contemporary rebuilds and the townhouse developments that have replaced some of the original stock.

The common thread in the period homes is suspended timber floors and walls that take a while to warm through. Hydronic radiators suit them well: pipework runs through the subfloor, so floors and walls stay intact, and a radiator under each window counters the cold down-draught from the glass. Melbourne has roughly 1,500 heating degree-days a year and a −1 °C heating design temperature, so the heating runs for a long season and correct radiator sizing pays back every winter. Tall Edwardian ceilings add volume and heat loss, which is why we never size radiators from floor area alone.

Heritage Overlays and where the plant goes

Heritage Overlays are common across Boroondara, so there is a good chance your street is covered by one. Inside the house, hydronic heating is about as heritage-friendly as heating gets. Radiators can be removed later without damage, ThermaSkirt skirting-board heating replaces the skirting and all but disappears, and there are no ducts cut through ceilings or floors. Outside, a heat pump is a visible piece of plant, so we site it at the rear or behind a side fence, clear of neighbours' bedroom windows. If your property is under a Heritage Overlay, check with the City of Boroondara whether a permit is needed before plant goes anywhere visible from the street.

Replacing an old gas hydronic boiler: three options

If your gas boiler is approaching 20 years old, losing pressure, cycling on and off, or needing parts that are hard to find, you have three realistic paths. Each keeps your existing pipework and most or all of your radiators; what changes is the heat source.

A condensing boiler only reaches its best efficiency when the water returning to it is cool enough for the flue gases to condense, so on a like-for-like swap we set flow temperatures and balance the radiators to suit, rather than simply bolting a new boiler onto old settings.

What a heat pump conversion involves

Most Camberwell gas radiator systems were designed around water at 70–80 °C. A heat pump runs most efficiently at lower temperatures, and a radiator's output can fall by roughly half when the water running through it is that much cooler. That does not rule out a conversion; it means checking the numbers room by room. A typical conversion runs like this:

1. Heat-loss check. We calculate each room's heat loss and compare it with what its existing radiator delivers at heat-pump water temperatures.
2. Radiator changes. Usually only a few rooms fall short, most often a large living room or a room with a lot of glass. Those radiators are upsized, typically to a deeper double or triple panel from the IMAS range, and the rest stay.
3. Flush and treat. Old systems carry sludge and corrosion debris that a gas boiler tolerated. We flush the circuit and dose it with inhibitor before the heat pump is connected.
4. Outdoor unit and power. The heat pump goes outside, usually at the rear, with a dedicated electrical circuit.
5. Changeover. The old boiler stays in service until the heat pump is commissioned, so you are not left without heating.

Fabric upgrades help too. Topping up ceiling insulation, insulating under the timber floor of a bungalow and sealing draughts around old windows and fireplaces all lower the heat loss, which can mean fewer radiators need upsizing. If your gas hot water service is also ageing, replacing it with a heat pump water heater such as the Viessmann Vitocal 161-A at the same time takes the house off gas entirely. A registered heat pump water heater may attract STCs; the air-to-water heat pump that heats your radiators does not, and Victorian Energy Upgrades heating incentives cover air-to-air reverse-cycle units rather than hydronic heat pumps. Our guide to replacing a gas hydronic boiler with a heat pump covers the process in more depth, and heat pump hydronic heating Melbourne covers equipment choices.

Underfloor heating in Camberwell extensions

Many Camberwell renovations keep the period rooms at the front and add an open-plan kitchen and living area at the rear on a new slab. That extension is the ideal place for underfloor heating: the pipework goes in before the slab or screed is poured, and the floor runs at 35–45 °C, which keeps a heat pump in its most efficient range. The original rooms keep their radiators, and one heat pump runs both, with the radiators sized to work at the lower temperature or a mixing valve on the underfloor circuit. In-slab underfloor responds over hours rather than minutes, so it is best run steadily through the heating season, while radiators look after bedrooms that only need heat morning and evening. If you are weighing the options, our comparison of ThermaSkirt vs radiators vs underfloor heating sets out the trade-offs.

When hydronic is not the right call

We will tell you if we do not think it is worth it. If your gas boiler is only a few years old and working well, it usually makes sense to improve insulation now and convert when the boiler is due. If you are planning a knock-down rebuild within a few years, a repair or a like-for-like boiler may be the sensible stop-gap. And in a small townhouse or apartment with a modest heating load, a reverse-cycle split system can do the job for less. Whole-home hydronic systems typically cost $20,000–$60,000+ installed and radiator systems $12,000–$30,000, so the system has to earn its place.

Serviced from Laverton North, across the inner east

Camberwell jobs are designed, installed and serviced by our own licensed plumbers and hydronic engineers from our Laverton North showroom, to AS/NZS 3500 and, for gas work, AS/NZS 5601. We work across Camberwell, Canterbury, Surrey Hills, Glen Iris, Balwyn and Ashburton, and in the neighbouring suburbs covered on our hydronic heating Kew, hydronic heating Hawthorn and hydronic heating Toorak pages. For radiator options across the city, see hydronic radiators Melbourne.