Is my hot water system worth repairing or replacing?

When the hot water plays up, the first question is always the same: is this worth fixing, or am I throwing good money after a system that is on its way out anyway? There is no need to guess. A few simple tests give you a clear answer most of the time.

The one-third rule

The handiest rule of thumb is the one-third rule. If the cost of the repair is more than about a third of what a new system would cost, replacing is usually the smarter spend. A $250 repair on a unit you would replace for $2,000 is easy: fix it. A $700 repair on that same unit, especially if it is getting old, is money better put towards a new one that comes with a fresh warranty and years of life.

It is not an absolute law, but it is a good starting point, and it stops you sinking repair after repair into a system that is quietly failing.

Age changes the answer

The same repair can be worth it on a young system and a waste on an old one. Set the one-third rule against the typical lifespans:

• Electric and gas storage tanks: about 10 to 12 years.
• Gas continuous flow: 15 to 20 years.
• Heat pumps: 10 to 15 years.

A five-year-old tank with a failed element or thermostat is well worth repairing. It has years left. The same fault on a twelve-year-old tank is a different story, because even if you fix it today, something else is likely close behind. As a rough line, once a system is past about three-quarters of its expected life, lean towards replacing.

When it is repair, and when it is replace

Some faults are clearly repairs, others clearly are not.

Usually worth repairing, especially on a younger system:

• A failed heating element or thermostat on an electric tank, which shows up as cold, lukewarm or fast-running water.
• A thermocouple, pilot or gas valve fault on a gas unit that will not stay lit.
• A stuck tempering valve or a worn relief valve.

Almost always a replacement:

• A leaking tank. Once the steel tank itself is rusted through and weeping, it cannot be repaired, only replaced. This is the one that ends the conversation.

Terry will always tell you honestly which side of that line your system sits on, rather than talk you into the bigger job.

The cost maths, and how rebates tip it

Put some numbers to it. Most hot water repairs land somewhere around $150 to $450 depending on the part. A new system varies by type: an electric tank fitted is roughly $1,500 to $2,500, a gas continuous flow unit about $1,900 to $3,500, and a heat pump around $3,500 to $5,500 before any rebate.

That heat pump figure is where rebates change the sum. Switching an old electric or gas system to a heat pump can combine federal STCs with the NSW Energy Savings Scheme incentive, together often worth roughly $1,000 to $2,500, taken off up front through an accredited supplier. That can bring a heat pump down close to the price of a plain tank, while cutting running costs to about a third. So a borderline repair-or-replace call on an older tank often tips towards replacing with a heat pump once the rebate is in the picture.

The honest answer depends on your exact system, its age and the fault, and Terry will give it to you straight with a fixed quote either way. If you are weighing up a repair against a new system, call Terry on 0415 274 542 and he will tell you which is the better spend.