Hot Water Cylinder Replacement in Christchurch: Costs, Options and Timing

Signs your cylinder is on the way out

• It's over 20 years old (check the compliance plate)
• Rusty or discoloured hot water
• Damp, staining or rust at the base of the cylinder cupboard
• Hot water runs out much faster than it used to
• Banging, rumbling or hissing as it heats
• The relief valve drips constantly

Low pressure vs mains pressure

Plenty of older Christchurch homes still run a low pressure copper cylinder fed from a header tank in the roof. They're reliable but the shower pressure is soft and you can't run two outlets well.

Mains pressure gives strong, even flow at every tap and is what most people upgrade to. It's a bigger job: the cylinder, valve set and often the pipework near it all get replaced, and the cylinder must be seismically restrained.

Gas continuous flow

If your home already has natural gas or LPG, a continuous flow unit hangs on an exterior wall, frees up the cupboard, and never runs out. It suits busy households and homes short on space. It needs a certified gasfitter and a compliance certificate.

Heat pump water heaters

Efficient, but they perform best with reasonable outdoor temperatures and need airflow and a condensate drain. In Christchurch's frostier suburbs we'll talk through placement and expected winter performance before recommending one.

What the job involves

Typically half a day to a day. We isolate and drain the old cylinder, remove it, fit the new unit with a compliant valve set and seismic restraints, refill, purge the air, check for leaks and test the temperature at the tapware. Tempering valves are required to keep sanitary fixtures at 55°C.

Frequently asked questions