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Plumbing guide

Water Heater Service: Tanks, Tankless, and When to Replace

Water heaters usually give some warning before they fail: not enough hot water, rumbling, discoloured water, or a small pool at the base. Knowing what those signs mean helps you decide whether to repair or plan a replacement before the failure becomes an emergency.

How long a water heater lasts

  • Standard tank heaters, roughly 8 to 12 years
  • Tankless units, 15 to 20 years with regular descaling
  • Life expectancy is shorter in areas with hard water and no softener
  • Rental units are usually replaced by the rental company at end of life

Signs a tank is failing

  • Rumbling or popping sound, sediment on the tank floor
  • Rusty or discoloured hot water, tank corrosion inside
  • Water pooling at the base of the tank, tank body has failed and cannot be repaired
  • Runs out of hot water quickly, thermostat, element, or dip tube issue
  • Pilot will not stay lit on a gas unit, thermocouple or gas valve

Repair or replace

If the leak is at a valve, fitting, or T&P valve, it is usually repairable. If the tank itself is leaking, it needs replacement. On a heater near or past its expected life, replacement is usually a better use of money than repeat repairs.

Tank vs tankless

  • Tank: lower up-front cost, higher standing losses, finite hot water supply per recovery cycle
  • Tankless: higher up-front cost and install complexity, unlimited hot water at a set flow rate, longer life
  • Tankless is a strong fit for high-usage households and long-term ownership, less compelling for very low-usage homes
  • Gas tankless usually needs a larger gas line and dedicated venting, factor that into the on-site pricing

What a replacement includes

  • Drain and disconnect the old unit
  • Set and level the new unit on a proper base or pan
  • New water connections, T&P discharge, gas or electrical hookup
  • Fill, purge, and test the unit under load
  • Haul away the old tank where possible

Need a plumber?

A specialist assesses the problem on site before any repair work is priced. Repair options and pricing are explained before approved work begins.

Frequently asked questions

Is a leaking water heater always an emergency?+

A leak from the tank body is. A drip from a valve or fitting can often wait for a normal appointment. Shut off power/gas and the cold-water inlet and call to confirm.

Can I install a water heater myself?+

Water heater installs involve gas or electrical work, venting, and permits in many areas. It is a licensed trade job.

How long does a replacement take?+

A like-for-like tank replacement is usually completed in a single visit. Tankless conversions and gas-line upgrades take longer.

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