The three realistic options
Option one: a like-for-like gas ducted changeover. Cheapest up front, uses your existing ductwork, and still the strongest performer for warming a whole older home quickly. You're tied to gas supply charges and gas prices.
Option two: ducted reverse cycle. Reuses the existing duct runs in most cases but needs an outdoor unit and correctly sized ducting. Higher up-front cost, one system for heating and cooling, no gas bill at all if you drop the gas connection entirely.
Option three: multiple split systems, no ducting. Cheapest running cost per room and the most efficient option overall, but you heat rooms individually rather than the whole house, and you get indoor heads on the walls.
What it actually costs
A gas ducted changeover on existing ductwork is usually the lowest install figure. Ducted reverse cycle typically lands materially higher because of the outdoor unit, electrical work and duct sizing. Two or three well-placed splits often come in between the two.
The number that catches people out is ductwork. A high-efficiency unit on 25-year-old uninsulated ducting will never deliver its rated output, so we assess the ducts before quoting either path — that's the difference between a quote that works and a cheap quote that disappoints.
Running cost, honestly
Reverse cycle produces roughly three to five units of heat per unit of electricity, so per unit of heat it's generally cheaper to run than gas at current Victorian prices — and cheaper again with solar, because it runs on your own generation.
The catch: reverse cycle is at its least efficient on the coldest mornings, which is exactly when the Bellarine wants heat. It still works, it just draws more. Gas ducted delivers big heat instantly regardless of outside temperature.
What we'd tell you on site
If your ductwork is sound, your gas heater is under about 12 years old and the fault is a cheap part — repair it. Don't rebuild a system that isn't dead.
If the heater is past 15 years, you have solar, or you're renovating anyway, electric reverse cycle is usually the better long-term call.
If you have no solar, a large draughty older home and a working gas connection, a gas ducted changeover is often still the sensible, cheaper decision. We'll quote both and let you choose.
Anything involving gas, refrigerant or the inside of the unit is licensed work. If you smell gas, shut the gas off at the meter and call the gas emergency line first.
We quote both paths side by side — gas changeover and electric reverse cycle — including the ductwork assessment, so you can compare real numbers for your house instead of averages.
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