How do I choose the right hot water system for my house?

Shopping around for a new hot water system is not something you do very often, but when you do, it’s quite a major purchasing decision. The new system you decide on is one you’re going to live with for up to 20 years, and it’s something that impacts so many of your household tasks. So you want to make sure you’re prepared with all the relevant information needed to make the right choice.

When we talk to customers who are trying to decide on a new hot water system for their home, we find that there are some common considerations they all have:

Reliability – You want assurance that there will be hot water when you need it; you won’t run out of hot water before you’ve all had a shower, done some washing up in the kitchen, etc.

Cost efficiency – You want to save money where possible on your power, gas or water bills.

Quality – You want to know that the system you install will last as long as possible and won’t give you any problems.

Suitability – You want to make sure that the system you choose will actually fit in your home.

These are all considerations we hear when talking to clients about how to choose the best hot water system for their property – whether that’s their primary home, their rental unit, or their holiday house.

So how do you choose, and what are the options that will satisfy these demands?

There are many different products available, and the research can be confusing. We’ve simplified it into the main categories of gas vs electric, low pressure vs mains pressure, and hot water cylinder vs continuous flow. We’d like to think that we’ve provided clear, helpful information on all of these, but if there is anything that you’re unsure of, please get in touch. We’d be happy to talk through what option(s) might be right for you.

Electric vs Gas Hot Water System

First we consider how you’re going to heat your water. Your current hot water system will be either electric or gas. If it’s electric, then you’ll be using a hot water cylinder to heat your water. We supply a large range of electric hot water cylinders from Rheem and Rinnai, two main brands that we know and trust. We will discuss with you whether you want to keep your cylinder inside (under the stairs or in a cylinder cupboard) or whether you want to free up space in the house and relocate your hot water cylinder outside.

The size of your hot water cylinder will be determined by a few things. Cylinders range in size from 30L to 300L, with the average or most common size being 180L.  We take into consideration what you have space for and how many people there are in the household. You don’t want a cylinder that is too large for your needs because you’ll end up paying to heat water that you’re not using.

If you’re using gas heat your water, then we’ll consider whether you want to stay with a hot water cylinder or upgrade to a gas hot water system (gas continuous flow water heater) – more on that below.

Low Pressure vs Mains Pressure

If you’re currently using a hot water cylinder, we look at whether you’re on low pressure or mains pressure water (the pressure of the water coming out of your hot water cylinder). Generally, a low pressure system provides water pressure at approximately 75 kpa, while a mains pressure hot water cylinder will provide up to 500 kpa.

Look for the sticker on your hot water cylinder that will say either “low” or “high” or read more here about low vs mains pressure water pressure.

Replacing your hot water cylinder is the time to consider upgrading from a low pressure hot water cylinder to a mains pressure hot water cylinder. For most households, it makes sense to do so. You’ll immediately notice the difference – your showers will feel better and you’ll probably be able to shorten shower times. Another important reason to upgrade from low to mains pressure is the requirement to do so if you think you’ll be doing any renovations to your kitchen or bathrooms in future. Modern tapware and mixers won’t work properly on a low pressure system, and it’s becoming harder to find specific lower pressure mixers (using mains pressure mixers on a lower pressure system actually makes the flow worse).

Hot Water Cylinder vs Continuous Flow

If you’re using gas to heat your water, we’ll discuss with you whether you want to continue to use a hot water cylinder or upgrade to a gas continuous flow hot water system.

With a hot water cylinder system, water is heated and stored in a cylinder, available to use as you need it. However, you’re limited to the amount of hot water in the cylinder. If you have a cylinder with a capacity of 180L, then once all of that is used, you need to wait for more water to be heated. (Opinions vary, but sources we consulted reported that we use on average 10 litres of water per minute in the shower; a 5-minute shower, therefore, uses 50 litres of water.)

Apart from showers, the average household also uses hot water for baths, washing hands, hand-washing dishes, general kitchen clean-up, cooking and filling the kettle (are you a cold water or hot water kettle filler?). Depending on the number of people in your household, then, it’s easy to run out of hot water after a few showers or a couple of showers and some washing up.

With a continuous flow system, water is heated as you use it – so you’ll sometimes hear this system referred to as instant hot water. You don’t store water in a hot water cylinder. Instead, water is heated as it passes through the heat exchanger – heat is produced by the gas burner that ignites when you turn on the hot tap (and extinguishes when you turn the tap off).

There are a number of benefits of switching over to a gas continuous flow water heater:

  • it provides an endless supply of hot water – no more running out of hot water after 2 or 3 showers
  • it doesn’t take up any room in the house, and very little space outside – a great option if you have a small outdoor area
  • it’s a much cheaper way to heat water than an electric hot water cylinder system – with continuous flow you only heat what you use, as you use it (rather than holding a cylinder full of hot water and keeping it hot when you’re not using it)
  • it’s an attractive feature that buyers will look for if you decide to sell your house in future

We’d love to talk to you about the options for heating the hot water used in your home … but if you’re interested get in touch with the knowledgeable team at Cylinder Direct for a no-obligation initial chat and we’ll help you determine what’s best for your home and your budget. Have a look at our hot water cylinder Installations page – then contact us.