Continuous Flow Hot Water Christchurch

A continuous flow water heater, often still called a califont, has no storage tank. When you open a hot tap, water runs through a heat exchanger, the burner lights, and hot water keeps coming for as long as you need it. No more last person in the shower getting the cold end of the cylinder.

In Christchurch these units run on LPG. We install, replace, repair and service them across the city, Selwyn and Waimakariri, sized properly for your household and fitted by a certifying gasfitter who hands over the gas certificate you are legally required to have.

Pricing: quotes are free, and every job gets a fixed price before we start, so there are no surprises on the invoice.

Continuous Flow Hot Water Jobs We Handle Across Christchurch

• Califont replacement
• Gas califont repairs
• Infinity hot water systems
• Instant gas hot water
• Electric to gas conversions
• Continuous flow servicing

LPG is the gas in Christchurch

There is no natural gas network in the South Island, so every gas water heater in Canterbury runs on LPG. Christchurch did once have a coal gas network from the old gasworks, but that closed in the early 1980s. Today the city's LPG arrives by pipeline from Lyttelton Port to storage at Woolston, and a continuous flow unit is supplied in one of three ways: If you would rather keep a stored tank of hot water on gas, see our gas hot water cylinder options.

• A pair of LPG bottles with an automatic changeover valve, the most common setup
• A larger bulk LPG tank, which suits homes with several gas appliances
• A piped LPG network in some Christchurch streets, run by Rockgas

Is continuous flow right for your home?

It suits many households, but not all. It works well when several people shower back to back and the cylinder keeps running out, when you want the cylinder cupboard back, or when you are replacing an old gas storage cylinder. If you would rather not have LPG deliveries at all, heat pump hot water or a mains pressure cylinder may suit you better, and we will price those honestly alongside a gas unit.

The other question is where the unit can go. It needs an outside wall, ideally close to the main bathroom, with room for the flue clearances and somewhere sensible for the bottles or tank. A long pipe run between the unit and the shower means a longer wait for hot water and more water wasted while you wait.

How It Works

Sizing for a Christchurch winter

Continuous flow units are rated by how many litres per minute they can heat. A small unit runs one shower; a large one can run two showers and the kitchen tap together. Undersize it and the water goes lukewarm when two outlets run at once, and that shows up most in winter, when the incoming water is colder and the unit has to lift its temperature further.

The LPG supply has to keep up too. A bigger unit draws more gas, and bottles deliver gas less freely on a very cold morning than on a mild afternoon. We check the bottle or tank arrangement, regulator and pipe size before we quote, so the unit gets the gas it needs at 7am in July, not just on paper.

Frost and the outside wall

Christchurch averages about 80 ground frost days a year, and in July 2026 the city dropped to minus 4.6 C. A continuous flow unit lives outside, and the most vulnerable parts are the exposed cold and hot pipes underneath it. Many outdoor models have built-in frost protection that relies on power, so a power cut or a switched-off unit on a frosty night removes that protection.

We insulate the exposed pipework, fit isolation and drain valves where they are easy to reach, and show you how to drain the unit if you are going away in winter. Master Plumbers warns that freezing can split pipes and fittings, and a split under a califont is one of the more common winter call-outs. If yours has already split, our burst pipe repairs team can help.

Repairs, servicing and Christchurch water

For hot water repairs we start with the error code on the controller. Common faults include ignition failure, flame sensing faults, blocked inlet filters, frost-damaged pipework and an empty bottle that the changeover valve did not catch. Many are fixed on the first visit.

Christchurch's council water comes from deep aquifers, and the council reports a typical total hardness of about 45 g/m3, which is at the soft end, so scaling of the heat exchanger tends to be slow. Private bores and tank water can be very different. A periodic service checks combustion, cleans filters and checks for scale, with the interval set to suit your water source and use.

What affects the cost

We give a free quote once we have seen your setup. The main cost drivers are the size of the unit, whether you are on bottles, a bulk tank or piped LPG, the distance from the gas supply to the unit, whether the gas pipe or regulator needs upgrading, how much hot water pipe needs rerouting, the removal of an old cylinder, and whether you want temperature controllers in the bathroom or kitchen.

Why Choose Cheeky's Plumbers for Continuous Flow Hot Water

Continuous Flow Hot Water FAQs

Continuous Flow Hot Water Across Christchurch

Our continuous flow hot water team works in every Christchurch suburb. Find your local plumbers:

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