Upgrade Your Old Hot Water Cylinder

If your hot water cylinder is nearing the end of its lifespan, you will need to look at replacing it. This is a great time to look at upgrading the model you’re using, especially if your current system is not meeting your household’s hot water requirements and a “like for like” replacement will not work.

A traditional hot water cylinder system has an average lifespan of about 8 to 12 years. Majority of the issues with your hot water cylinder can be fixed by replacing the part causing the issues and maintaining the cylinder regularly.

If you’d like to discuss your options for hot water cylinder upgrade, contact us today on 0508786424 for advice and a quote on upgrading your hot water cylinder

There are several ways in which you can upgrade your hot water system

Size of Hot Water Cylinder

The size of your cylinder can be very important when upgrading your hot water system. Hot water cylinders come in a range of sizes from 30L to 300L. If you find yourself trying to time your shower perfectly to get a consistent stream of hot water, or you have several people in your household fighting to shower first while there is still hot water, it may be time to increase the capacity of your hot water cylinder.

There are three main capacities currently recommended for households of various sizes. It is estimated the average person uses 50L of hot water a day. In a household of 2 to 3 people, it is recommended you install a 180L unit. In a household with 2 to 5 people, a 250L unit is recommended. In a household of 3-5 people, a 300L unit is recommended.

There are some factors that can influence your hot water use, the first being a long hot shower. Some shower heads can dispense up to 20L per minute. Using the dishwasher often can result in above-average hot water usage as the average dishwasher uses 10 to 12 litres of hot water per wash. A smaller cylinder may seem like a good idea, but opting for a larger capacity (if you have space) will be more beneficial in the long run.


There are newer models available on the market with more advanced technologies that allow the hot water cylinder to learn from your hot water use patterns to heat the water more efficiently. This can result in up to 10% savings on your water heating bill.

One of the leading hot water cylinder manufacturers in New Zealand has produced the Rinnai Smart Cylinder. A traditional hot water cylinder heats up water 24 hours a day, 7 days a week, 52 weeks a year, and of course, you pay for this. The Rinnai Smart Cylinder has a thermostat that learns the pattern of hot water use in your house, allowing it to only heat water when it knows it will be needed.

The cylinder has a LCD control pad, allowing you to control the mode. The system has an IQ Mode for learning your patterns, a manual mode for overriding these patterns and a vacation mode to save power and money if you regularly go away on holiday. This advanced smart thermostat can be compatible with low and mains pressure hot water cylinders, the capacity for these cylinders ranges from 135L to 250L.

Future-Proofing with Solar Water Heating

You can also install a new hot water cylinder to replace your old one while future-proofing your hot water system. There are several hot water cylinders on the market that allows for future connection to a solar system, a heat pump water heater and a wetback. This allows you to expand your hot water system in the future to be more energy efficient.

With solar water heating, timing is very important. If you think about solar power in advance, you can save a lot of money in the future by installing a system that is already compatible. If you decided to go with this option, make sure you add solar panels as an option to your building consent, you have two years to install them, and it will save you time and money when the time is right.

Solar ready hot water cylinder should come with options for both closed and open loops; double protection for high temperature; auto-reset thermostats; dedicated probe pockets and a temperature gauge. These principles also apply for adding a heat pump or wetback system.

Take the time to research each of the future-proofing systems, comparing the advantages and disadvantages; this will pay off in the long run. The cost of cylinders for future-proofing systems are very similar to those that do not allow future-proofing, making it an easy choice. 

Water Pressure

There are two types of hot water cylinders when comparing water pressure, low-pressure hot water cylinders and mains pressure hot water cylinders. If you find your hot water pressure a little lackluster, you may have a low-pressure system.

This could be the opportune time to upgrade to a high-pressure system. The main difference is the mains pressure hot water cylinders delivers hot and cold water to outlets at the same pressure, low-pressure hot water cylinders supply hot water to outlets at low pressure and cold water at mains pressure.

Upgrading to a mains pressure hot water system means the heating system can cope a lot better with multiple hot water demands at the same time while reducing temperature variations at outlets. This means you could run hot water outlets in multiple showers at the same time or in the kitchen and bathrooms.

This improvement may be a huge success with the rest of your household when fights over a hot shower become a thing of the past. 

You can also upgrade your hot water cylinder by incorporating all of the upgrades noted above. If you’d like to discuss your options, contact us today on 0508786424 for advice and a quote on upgrading your hot water cylinder. 

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