How do I know if my hot water cylinder needs replacing?

Most of the time, the obvious signal that your hot water cylinder needs replacing is the shouting that comes from the bathroom when someone encounters a cold shower. But that’s not always the first sign that something is wrong, And it’s not necessarily a definite sign that your hot water cylinder needs replacing – a repair may suffice.

Your hot water system might be an area of home maintenance that you’re a bit sketchy about – even if you are a handy Kiwi DIYer. So we’ll shed some light on the issue here, and give you some tips about whether you need to replace or repair your hot water cylinder.

Out of sight, out of mind

If your hot water cylinder is inside the house (not all of them are; some are outside, beside the house), it’s probably in a space under the stairs or in a closet or cylinder cupboard. If you’re not sure where it is, first have a look in the linen/towel cupboard – it’s still common for people to store their linen beside the hot water cylinder to have it dry and warm.

Many homeowners (and certainly most tenants) don’t regularly check that their hot water cylinder is in good working order. It’s not usually something you think about until you suspect it’s not working properly.

What are the signs that there’s something wrong with your hot water cylinder?

There are a few common issues that indicate that your system isn’t working properly:

  • you experience a drop in water pressure
  • you notice a drop in temperature of your water – or erratic fluctuations between hot/cold water
  • you turn on the hot tap and have no hot water at all (even after waiting a minute or so)
  • you hear unusual sounds, banging or hissing coming from the hot water system
  • there is water leaking from your hot water cylinder
  • there is a steady stream of water flowing from a copper pipe outside of your house

Any of these is a warning sign that your hot water cylinder might not be functioning properly.

Please note that there should not be water “leaking” from your cylinder, but there will always be a small amount of water released from the cylinder from a valve connected to the cylinder. This should be a slow drip (of approximately one to two litres a day), not a leak or constant drain of any more than that.

Does the age of a water cylinder determine whether it needs replacing?

Sometimes, yes, the age of a water cylinder can help you decide whether you need to replace it.

In another article titled “How long does an electric water heater last?” we go into more detail about how long a hot water cylinder should last. In short, however, if your water cylinder is over 15 years old and you experience any of the issues listed above, then it is probably a good time to replace your hot water cylinder.

This might also be a good opportunity to review any changes in system that would be of benefit to your household:

The experienced team at Cylinder Direct can handle any of these change-overs for you. We are registered gasfitters authorised by the Plumbers, Gasfitters, and Drainlayers Board to do this work.

How do we know if the hot water cylinder needs repairing or replacing?

At Cylinder Direct, we do what we can to keep old cylinders out of landfill. We will always consider repairing before replacing if we can and if the cylinder isn’t old enough to need replacing. And we recycle old hot water tanks whenever possible.

Our diagnosis starts with two questions:

  1. How old is the hot water cylinder?
  2. What are the signs that something is not working properly?

Often we can ask you these questions over the phone and do an initial verbal consultation about what the best course of action might be. If not, we’ll come out and see you at your home to have a look at what the issues are and to inspect the condition of the cylinder system. Sometimes it’s necessary to have a closer look or listen to see what’s wrong.

The cylinder system is made up of various components – a steel outer casing, thermal insulation, and then an inner copper, steel, or stainless-steel tank. In addition, there is a thermostat, and several parts and valves. There may be a fault with any of these components, causing the problems with your water temperature or flow that you’re experiencing.

If the inner tank is cracked or damaged (either due to age or from wear and tear if it has been moved), water may leak from it. This is the most common cause of a water tank leak. An inner tank cannot be repaired; it will need to be replaced.

If the damage lies within any of the other components, we’ll look into whether replacement valves will do the trick or if a new thermostat will solve the problem. As always, we’ll do what we can to keep your hot water cylinder system running efficiently and safely for as long as possible.

If you suspect there is something not working quite right with your hot water system, just give us a call. Remember, with Cylinder Direct there is no middle-man and not sub-contractors … the people you deal with on the phone are the people who come out to see you.