How Long Does a Hot Water System Take To Heat Up?

Ever been hit with an icy blast when you're expecting a warm shower? It's one of the most frustrating things to start your day with. When your hot water system isn't delivering, it's natural to wonder how long it should actually take to heat up.

As your local plumbing experts in Newcastle, we're here to help. This knowledge will not only help you plan better but also identify a problem before it becomes a major inconvenience. We'll explain the typical heating times for different systems and what can affect them, so you can keep the hot water flowing.

Factors influencing heating time

The time it takes for your hot water system to heat up depends on a few important things, including the type of system you have, its size, and the energy source it uses. Understanding these variables can help you figure out what to expect.

Different types of hot water systems and their duration to heat up.

Solar Hot Water and Heat Pumps:

Average water heating time: 1–5 hours (depending on sunlight and system type)
Benefit: It's great to find a hot water solution that not only helps you save money but also lowers your environmental footprint. Solar hot water systems and heat pumps do just that. They can dramatically reduce your energy bills, and in many cases, they may also be eligible for government incentives.

Electric Hot Water:

Average water heating time: 1–2 hours

A standard 160L tank: about 1 hour and 30 minutes to heat.

Benefit: Electric systems are a popular choice and come in a wide range of sizes, from smaller 25-litre tanks to 400 litres. This makes it easy to find a size that’s right for your home. While the running costs can vary depending on your energy tariff, these systems are a reliable and safe choice.

Gas Hot Water:

Average water heating time: 30–40 minutes

A standard 135L gas storage tank: heats up in under 40 minutes.

Benefit: Gas storage systems might not come in as many sizes as their electric counterparts, but they can hold a significant amount of hot water and have an excellent recovery rate. They can also be purchased to work with either LPG or natural gas.

Tank size:

The size of your hot water tank is a significant factor in determining how long it takes to heat up.

Small tanks (50-100L): These heat up quite fast. Gas models will typically be ready in about 20-30 minutes, while electric models can take around 45-60 minutes.

Medium tanks (150-250L): These are commonly used by families. You might have to wait 40-50 minutes for a gas system and over an hour for an electric one.

Large tanks (315L+): For bigger homes or those with a high hot water demand, these can take over an hour with a gas system and up to two hours or more with an electric system.

Common Reasons Hot Water Takes Too Long to Heat

If you're experiencing long wait times, it’s a good sign that something isn’t quite right. Here are some common reasons why your hot water may be taking too long to heat.

Sediment Build-Up

Over time, minerals from your water can settle at the bottom of the hot water tank. This sediment acts like insulation around the heating element, making it work much harder to warm the water.

Faulty Heating Elements

If you have an electric hot water tank, it may have more than one heating element. If one of these burns out, it can cause delays because the other aspects have to take on all the work, which they aren't designed to do alone.

Thermostat Issues

A thermostat that isn't working correctly can trick your system into thinking the water is hotter than it actually is. The result is often lukewarm water and frustratingly long wait times.

Undersized System

Has your household grown over the years? More people, more showers, or even a bigger washing machine can put a strain on your current hot water system. If it's constantly having to recover, it's a sign that it may be undersized for your needs.

Weather, Environment & Initial water temperature

One last thing to remember is the temperature of the water coming into your home. For solar and heat pump systems, factors such as cold weather, shaded roofs, or poor ventilation can extend heating times. These systems rely on their environment, so a change in conditions can affect their performance. The colder the incoming water is, the longer your system will have to work to get it up to the desired temperature. This is something to keep in mind, especially during the colder months here in Newcastle and the Hunter Valley.

Looking to upgrade?

Hot water systems play a significant role in day-to-day comfort, so when they take too long to heat up, it's an indicator that something's wrong. Using the knowledge you've gained from this post can help you understand when your system is struggling.

If your system consistently takes too long to heat, it’s time to seek professional help. Enviromate Plumbing has all your hot water needs covered with fully licensed technicians on call, 7 days a week. We can service, repair, or replace any type of hot water system, and we offer same-day service at a competitive price.