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Energy efficient water heating

Immersion heaters

Immersion heaters are a convenient way to heat water, and allow you to heat as much or as little as you need. However, you can save up to 30% on your running costs by taking a few simple steps.

Running Costs

Heating one full cylinder each day (normally 120 litres) will cost about €1.30 per day, although actual usage costs will vary depending on cylinder size and the demand for hot water.
It takes about 2.5 hours to fully heat 120 litres from cold.
Heating a smaller quantity (normally 40 litres) using the "sink" switch will cost about €0.45 and take about 50 minutes to fully heat.
Check our Appliance Calculator for more detailed information on running costs.

Reduce Running Costs

STEP 1 - Insulate the cylinder
Insulate the hot water cylinder using a good quality, 80mm (3") thick lagging jacket and follow the manufacturer�s fitting instructions carefully. This will save up to 30% on your water heating costs and will pay for itself in a matter of months. Be sure to buy a lagging jacket that meets internationally approved standards. You should also insulate water pipes inside the hot press area. Buy a factory-insulated hot water cylinder if you are replacing your old one. Talk to your plumber about the best options.

STEP 1 - Insulate the cylinder

Insulate the hot water cylinder using a good quality, 80mm (3") thick lagging jacket and follow the manufacturer�s fitting instructions carefully. This will save up to 30% on your water heating costs and will pay for itself in a matter of months. Be sure to buy a lagging jacket that meets internationally approved standards.
You should also insulate water pipes inside the hot press area.
Buy a factory-insulated hot water cylinder if you are replacing your old one. Talk to your plumber about the best options.

STEP 2 - Control the immersion heater
Install a count-down timer for occasional hot water requirements. These require just a simple push of a button to give you just the right amount of hot water that you need. For regular hot water requirements use a programmable time switch that will supply hot water when you need it. These will also prevent your immersion from running longer than necessary. Choose one with a timed boost facility to allow a manual top up of hot water when required.

STEP 2 - Control the immersion heater

Install a count-down timer for occasional hot water requirements. These require just a simple push of a button to give you just the right amount of hot water that you need.

For regular hot water requirements use a programmable time switch that will supply hot water when you need it. These will also prevent your immersion from running longer than necessary. Choose one with a timed boost facility to allow a manual top up of hot water when required.

Tips

You should also consider having the sink/bath switch and time switch located outside the hot press for ease of access.
If your immersion element regularly fails because of lime build up then consider buying a replacement element with an Incoloy Sheath. It will cost a little more than the standard copper element but it will last longer.