Hot water system guide: repair or replace?
Most storage hot water systems last 8 to 12 years, and they usually fail without much warning, often by leaking. This guide covers the warning signs, when a repair makes sense, how to choose between gas, electric and heat pump, and what size you need. It's written by the local plumbers who look after hot water across Matraville, Maroubra, Malabar, Botany and the southern Eastern Suburbs.
Warning signs your hot water system is failing
- Water pooling or rust around the base of the tank
- Rusty or discoloured hot water
- Running out of hot water sooner than you used to
- Rumbling, popping or banging from the tank
- The relief valve dripping constantly, not just while it heats
- The system is more than 10 years old (check the date on the label)
Replacing a tank before it fails means you choose the time, the system and the price, instead of taking whatever's available on a cold morning.
Repair or replace?
Relief valve leaking
Usually a repair: the valve is replaced.
Gas pilot or thermostat fault
Usually a repair.
Electric element failed
Usually a repair.
Tank leaking from the body
Replace. A leaking tank can't be fixed.
Over 10 years old and needs a major part
Replacing is usually better value.
We'll tell you honestly which makes sense, and you get clear options and a fixed price before any work starts.
Gas, electric or heat pump?
The right choice depends on what's already connected at your home, how many people live there and how long you plan to stay.
Heat pump
Lowest running cost. Works like a reverse air conditioner, pulling heat from the air into the water, and uses far less electricity than a standard electric tank. Needs outdoor space and makes a quiet fan noise. NSW rebates may be available. Heat pump hot water →
Gas continuous flow
Never runs out. Heats water only when you turn on a tap, mounted compactly on an outside wall. Needs a suitable gas supply and meter. Continuous flow →
Gas storage
A simple like-for-like swap that recovers quickly, good for larger families. The tank loses some heat standing.
Electric storage
Lowest cost to buy, often on a cheaper off-peak tariff, but the highest running cost of the four. Can run out on busy days if it's undersized.
What size do you need?
A rough guide only. We size it properly on site, based on your bathrooms, appliances and how your household uses water.
- 1 to 2 people: electric 125 to 160 litres, gas storage 90 to 135 litres, heat pump 160 to 220 litres, or continuous flow 16 to 20 litres a minute.
- 3 to 4 people: electric 250 litres, gas storage 135 to 170 litres, heat pump 220 to 270 litres, or continuous flow 20 to 26 litres a minute.
- 5 or more: electric 315 litres or more, gas storage 170 litres or more, heat pump 270 litres or more, or continuous flow 26 litres a minute or more.
Make your hot water system last
- Every 6 months: gently lift the relief valve lever for a few seconds, then let it snap back. Careful, the water is hot. If no water comes out, or it won't stop, call us.
- Every 5 years: have the relief valve replaced, as most manufacturers recommend, and the sacrificial anode checked on storage tanks.
- Heat pumps: keep the air around the unit clear of plants and clutter.
- Gas units: service as per the manufacturer's guide.
Safe temperatures
Storage systems must heat water to at least 60°C to stop bacteria growing. A tempering valve then mixes it down so bathroom taps deliver no more than 50°C, which helps prevent scalds. If your bathroom water is too hot, ask us to check your tempering valve.
If your tank is leaking right now
Turn off the cold water valve on the inlet pipe to the tank. For electric systems, switch off the hot water circuit at the switchboard; for gas, turn the unit to off or pilot. Then give us a call.
Hot water in older southern Eastern Suburbs homes
A lot of homes in Matraville, Maroubra, Malabar, Pagewood and Botany are on their second or third hot water tank, often tucked down a narrow side passage or in the laundry. Many older installs have no tempering valve and old copper or galvanised pipework around the unit. Near the beach, salt air also shortens the life of outdoor tanks and fittings. When we replace a system, it's fitted to current standards and you get the compliance paperwork.
Why locals call us for hot water
- Based in Matraville, close to every southern Eastern Suburbs home
- 100+ five-star Google reviews
- Free quotes, and a fixed price before any work starts
- Lifetime labour warranty on our workmanship
- Licensed plumbers and gasfitters (Lic. 398171C)
Common questions
How long does a hot water system last?
Most storage systems last 8 to 12 years. Water quality, water pressure and maintenance all make a difference.
Can a leaking hot water tank be repaired?
Not if the tank itself is leaking. A leaking relief valve or fitting can usually be repaired, but a leak from the tank body means it's time to replace it.
Is a heat pump worth it?
For many homes, yes. It uses far less electricity than an electric tank, and NSW rebates may be available. It needs outdoor space with good airflow.
How much does a new hot water system cost?
It depends on the type, size and how it's installed. We come out, look at your current system and quote on site for free.
Need help with hot water? See our hot water repairs and hot water replacement services, or find your local page: hot water Matraville, Maroubra, Malabar, Pagewood, Eastgardens, Botany and Little Bay. More plumbing guides.