Hot Water Unit Servicing

How To Perform Routine Servicing On Your Hot Water Unit Without A Plumber.

Frequently testing and changing your TPR valve can prevent your tank from bursting.

It’s not hard to forget exactly how much we rely on our hot water systems. Taking a shower, preparing food, washing up; most people only appreciate just how important their hot water tank is when it fails. Murphy’s Law determines that this generally happens in a very spectacular fashion, in the earliest hours of a really wintry Sunday morning when every plumber in your area is on breaks…

Hot water units might appear a bit complicated and mysterious, but like all other parts of your house they will benefit greatly from a little bit of routine maintenance. This is particularly the situation with hot water units – simply because continuous flow hot water units don’t store hot water and are less likely to build up any pressure, they require far less attention.

Effective Servicing Of Your Hot Water Unit Is Fairly Easy.

Effective servicing of your hot water unit is fairly easy, and can double or triple the effective life expectancy of your hot water unit. To take care of your system, there’s two main things you will need to consider:

• the sacrificial anode

• the temperature and pressure relief valve (TPR valve for short).

What exactly is a sacrificial anode?

Most tank-based hot water units feature what’s called a ‘sacrificial anode’. A sacrificial anode is a metal rod, usually made from aluminium or magnesium and coated in zinc, that hangs down inside your hot water unit.

The sacrificial anode was designed to attract minerals and impurities in the water which would otherwise react with the inside of the tank and cause it to corrode and deteriorate. This ‘sacrificial’ rod gradually rusts and degrades, sacrificing its own life for the greater good of your hot water unit.

Probably the most important aspect of your hot water unit upkeep is regularly changing your sacrificial anode whenever necessary.

When do I need to replace my sacrificial anode?

Generally and depending on the properties of the water in your town) sacrificial anodes should be replaced once every five years. Failure to replace a sacrificial anode is just about the biggest single reason for hot water tank failure. If you are careful and replace your sacrificial anode on a regular basis, you can easily increase the service life of your hot water unit by another five years, ten years or maybe more.

How to change a sacrificial anode

To be clear from the outset – changing a sacrificial anode is not really a job you ought to perform yourself. Hot water tanks contain scalding hot water and vapor, and are normally connected directly to either a gas supply, or to electricity (which is extremely hazardous around water).

Once every 5 years (or at the length of time suggested by the manufacturer) it is best to hire a qualified, properly licensed plumber in your town to service your hot water unit and replace the sacrificial anode. The expense of employing a qualified contractor to service your hot water unit is small compared to the many thousands you’d otherwise need to pay to get another one.

What are temperature and pressure relief (TPR) valves?

Temperature and pressure relief valves are commonly known as TPR valves or T&P valves. These valves are fitted to hot water units as a secondary safety measure (see image).

TPR valves operate by automatically ‘venting’ hot water should the temperature or pressure of the water in the tank gets too high, in order to help prevent it from splitting or exploding.

Many people don’t realise it, but If your TPR valve isn’t working correctly, it has the potential to pose quite a serious risk – water heaters left to their own devices with malfunctioning TPR valves have been known to blow up.

How you can test out your temperature and pressure relief (TPR) valve

Flushing and testing a TPR valve is fairly simple, and some thing you can perform yourself. If the valve is currently leaking water through the outlet pipe, it’ll need to be changed. Testing the valve requires expelling some extremely hot water, so If you are going to test your TPR valve, make sure that you’re wearing long pants, covered footwear and gloves:

• Check to ensure the area within the outlet water pipe from the TPR valve is clear and free from obstructions. Make sure you are standing as far away as you possibly can from the end of the water pipe.

• Gently lift the handle on the TPR valve. If it is jammed, do not force it. If it does not want to move, you need to change it. When you lift the valve handle, very hot water should flow out from the end of the outlet water pipe.

• Gently return the valve to its closed position. The flow of water should stop. If it does not, this probably suggests that the valve isn’t functioning reliably and requires to be changed.

How frequently should temperature and pressure relief (TPR) valves be tested and changed?

Ideally, you need to refer to the manufacturer’s advice on how frequently to test your TPR valve – although as a rule of thumb this is usually something you ought to do once every 6 months.

TPR valves have a limited rated service life too, and need to be changed periodically. Again, how frequently they should be replaced depends on what’s advised by the manufacturer. In many instances this is something you will need to do once every a couple of years.

How to change a temperature and pressure relief valve (TPR valve)

Again, any work that is performed on your hot water unit should be done by a licensed hot water service contractor (i.e. a plumber with the relevant license and qualifications). If your TPR valve needs changing, call a plumber in your town to have it changed.