Gas or electric water heater?

Side-by-side comparison

The table covers supply, rules and safety, not prices.

Should you choose a gas water heater or an electric one?

The gas vs electric heater choice starts with supply. A gas water heater needs a gas supply, so check first whether your home has piped town gas. Electric instantaneous, storage and heat pump heaters run on electricity.

Next, check the installation rules, which include extra conditions from HDB for gas in an HDB flat. Then compare efficiency on the Energy Label, which rates every type.

What you pay depends on the heater and the job. See the water heater replacement cost guide, or browse water heater services to compare companies.

Gas supply in your home

Piped town gas can only be turned on by City Energy or its appointed agents, according to City Energy. SP Group says gas activation is managed separately from your SP utilities account: once that account is confirmed, you call City Energy to arrange an appointment. If gas supply is transferred to you from a previous occupant, City Energy encourages an inspection by City Energy or an LGSW.

Installation rules and licensed workers

Gas water heaters

HDB's renovation guidelines for plumbing and gas works say a gas water heater must comply with City Energy's requirements and be installed by an LGSW. Outdoor installation is subject to HDB's approval. Gas pipe termination and gas appliances are not allowed in sleeping areas or bedrooms; a full-height wall with a door must separate them.

City Energy says installing, replacing or removing gas appliances, and installing or altering gas pipes, may only be done by City Energy or an LGSW.

Electric water heaters

The Consumer Product Safety Office (CPSO) says to hire a Licensed Electrical Worker so the heater is properly wired: directly to the mains through a double pole switch, not to a 3-pin socket outlet, extension cord or multi-way outlet.

EMA says electrical work in an HDB flat needs a Licensed Electrician, the class of LEW approved for loads of up to 45kVA. EMA also says to verify the LEW's licence card before any electrical work starts.

Read about water heater installation steps before you book.

Efficiency, running cost and the Energy Label

NEA's Energy Label rates efficiency in ticks, from 1 (Low) to 5 (Excellent). For water heaters it shows the type (electric instantaneous, gas instantaneous, electric storage or heat pump) and, for storage heaters, the capacity in litres.

The label also gives an annual energy cost under fixed assumptions: 27 cents per kWh for electric water heaters and 22 cents per kWh of gas for gas instantaneous heaters, both with 3 showers a day. These are NEA's label assumptions, not current tariffs, so your running cost depends on the model and your tariffs.

NEA's Resource Efficiency Guide for New Home Owners advises choosing an instantaneous water heater over a storage water heater, as it is more energy efficient. A storage heater keeps using energy while left switched on; an instantaneous heater only uses energy when water flows through it. The guide also says an electric heat pump water heater is more energy efficient than an electric instantaneous or storage heater.

For electric models, see instant vs storage heater running cost or browse instant water heaters.

Safety

Gas water heaters

City Energy advises installing gas appliances in well-ventilated areas, and says it is advisable to have gas pipes and kitchen appliances checked by an LGSW once every five years.

Electric water heaters

The Consumer Product Safety Office says instantaneous and storage electric water heaters are Controlled Goods and must carry the SAFETY Mark before they can be sold in Singapore. Make sure a storage heater has a pressure relief valve. Do not use a heater that appears damaged or is leaking, and do not repair it yourself.

CPSO's SAFETY Mark guidance explains how to check a mark's 8-digit registration number. See also water heater warning signs.

Which one should you choose?

Start from your situation.

• Town gas and space for a compliant installation. A gas instantaneous heater is an option. Plan the location with an LGSW; in an HDB flat, it cannot go in a bedroom or sleeping area.
• No gas supply. Look at electric instantaneous, storage or heat pump models and compare their Energy Labels.
• Replacing like for like. Replacing a gas heater is gas appliance work for City Energy or an LGSW. For an electric heater, check that it is wired through a double pole switch.
• Small household. If you prefer a storage heater, NEA suggests choosing a capacity that meets your needs.

Questions