Do I need an electrician as well as a plumber to install a water heater?

For instant or tankless units, usually yes, since they typically need a dedicated circuit breaker. Some plumbers coordinate this directly, others will tell you to arrange it separately.

What size water heater do I need for my household?

It depends on the number of bathrooms used at the same time and hot water demand. A plumber can size this based on your household rather than guessing from tank litres alone.

Can an instant water heater work with low water pressure?

Not reliably. Instant heaters need a minimum flow rate to ignite and heat properly, so a plumber will usually check your pressure before recommending one over a storage tank model.

How long does installation take?

A straightforward replacement in the same spot is usually a same-day job. A first-time install that needs new wiring or pipe rerouting takes longer.

New water heater installation service

Putting in a new water heater is a different job from repairing an existing one. It starts with choosing between a storage tank heater or an instant/tankless unit, sizing it correctly for the number of bathrooms and household size, and working out the wiring and plumbing connections needed.

Instant water heaters draw a lot of current and usually need a dedicated circuit breaker, which means coordinating with an electrician or a plumber who works with one. They also need a minimum water pressure to fire properly, which matters in landed houses on gravity-fed tanks. Storage heaters need a sturdy wall or ceiling mount and space for the tank, plus a pressure relief valve set up correctly.

If this is a replacement rather than a first install, the job also includes disconnecting and disposing of the old unit and checking that the existing pipework and wiring are still suitable for the new one.

What it costs

Cost is driven by the unit type and brand you choose, whether new wiring or a dedicated circuit breaker is needed, how much the pipe or mounting position has to change from the old setup, and disposal of the old unit. Get a plumber to assess the site before settling on a specific model, since pressure and wiring constraints can rule some units out.

Top 3 by our score

Ranked from our published scoring of public Google reviews for water heater installation & repair.

1. LS Electrical & Plumbing
4.9★ · 149 reviews

91
2. BP Plumbing kl
4.9★ · 120 reviews

90
3. AlphaWater - Toilet, Sink, Drain Unclogging & Plumbing Service
5.0★ · 208 reviews

90

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FAQ

Do I need an electrician as well as a plumber to install a water heater?: For instant or tankless units, usually yes, since they typically need a dedicated circuit breaker. Some plumbers coordinate this directly, others will tell you to arrange it separately.
What size water heater do I need for my household?: It depends on the number of bathrooms used at the same time and hot water demand. A plumber can size this based on your household rather than guessing from tank litres alone.
Can an instant water heater work with low water pressure?: Not reliably. Instant heaters need a minimum flow rate to ignite and heat properly, so a plumber will usually check your pressure before recommending one over a storage tank model.
How long does installation take?: A straightforward replacement in the same spot is usually a same-day job. A first-time install that needs new wiring or pipe rerouting takes longer.

When you submit an enquiry through our contact forms, we may pass it to partner providers who can do the work, and we may receive a referral fee. Our rankings and scores are based only on our published scoring method and are never affected by referral fees.