Moving into a house with oil heating: a starter guide

How does oil central heating work?

There are three parts. The tank, usually outside, holds the oil. A pipe runs from the tank to the boiler, with a filter and a fire valve along the way. The boiler burns the oil to heat water, which is pumped round your radiators and, in most homes, heats the hot water cylinder too. A timer and thermostat tell it when to run.

Unlike gas or electricity, you pay for oil up front when it is delivered. If the tank runs dry, the heating and often the hot water stop until the next delivery arrives.

Where is the oil tank?

Most tanks are in the back garden, along a side passage or beside a shed. Some older houses have one in a garage or outhouse. Look for a large green or black plastic tank, or a steel one, with a pipe running towards the house. If you cannot find it, ask the seller, the estate agent or the previous owner's oil supplier.

While you are there, look at its condition. Cracks, bulges, rust, damp ground or a smell of oil all need attention. A tank with a second outer skin (a bunded tank) holds leaks better than a single-skin one. Our guides to single-skin vs bunded tanks and what to do if your oil tank is leaking explain more. If oil is escaping, do not hose it away. Call an OFTEC-registered technician, and tell your local authority if it could reach a drain or watercourse.

How much oil is in the tank?

Check this on day one. Many sales hand over a tank close to empty. Most tanks have a sight tube or a dial gauge on top, and some have a remote monitor that sends a reading indoors. With no gauge, a clean dipstick through the fill cap gives a rough depth. Our guide to checking your oil tank level walks through each method.

Note the size of the tank too. It is often printed on a label on the side. You need it to know how much to order.

Kerosene or gas oil?

Most Irish home boilers burn kerosene, also called 28-second oil. A few older systems use gas oil, the 35-second fuel known as green diesel. They do not mix. Check the boiler data plate, an old delivery docket, or ask the technician who services it. Our guide to kerosene vs gas oil covers how to check.

How do you order your first delivery?

Ring or order online with an oil supplier that delivers to your area. You tell them the fuel, how many litres or how many euro worth, your address and any access notes. Delivery times vary by oil supplier and get longer in a cold snap, so ask when you order.

For a sense of cost, the typical delivered price for 500 litres of kerosene from Irish oil suppliers is €828.50 (prices checked 12 October 2026). Your price depends on county, amount and oil supplier.

Order before the tank is close to empty. Running dry can draw sludge into the line and stop the boiler.
Ask whether there is a minimum order and whether the price includes VAT and delivery.
Leave room in the tank. Never order more than the tank can take.

Our step-by-step guide to ordering heating oil has more, and how much heating oil do I need? helps you pick an amount.

Can the oil truck reach your tank?

Ask yourself these before the first delivery, and tell the oil supplier the answers:

How far is the tank from where a truck can park? Ask the oil supplier how far their hose reaches.
Is there a locked gate, a dog, or a narrow lane a large truck cannot use?
Can the driver see and open the fill cap? Is it locked, and where is the key?
Is the fill point clear of plants and clutter, and is the tank vent free?

If the tank is hard to reach, the oil supplier may need to send a smaller truck. Ask whether that changes the price.

When was the boiler last serviced?

Ask the seller or landlord for the service records. A technician usually leaves a written record or a sticker on the boiler with the date. If there is nothing from the last 12 months, book a service. The NSAI advises a yearly service for oil boilers, and SEAI recommends booking it before the heating season. Use an OFTEC-registered technician. Our guide to oil boiler service costs covers prices and what the visit should include.

If you rent, the rented housing standards regulations say your landlord must keep heating appliances safe and in good repair, and provide carbon monoxide alarms where necessary.

Do you need a carbon monoxide alarm?

Yes, fit one. Any oil boiler can produce carbon monoxide if it is faulty or the flue is blocked. The NSAI advises an alarm that meets EN 50291, placed in each room with a fuel-burning appliance and in or near bedrooms. Gas Networks Ireland gives the same standard and adds that it should be audible and carry an independent certification mark (Gas Networks Ireland: carbon monoxide). Replace it when it reaches its expiry date.

If the alarm sounds, or anyone has headaches, dizziness or nausea that ease outside, turn off the boiler, get everyone out into fresh air and call 112 or 999. Do not use the boiler again until a technician has checked it.

Learn the controls

Find the timer or programmer, the room thermostat and the thermostatic valves on the radiators. Set the heating to come on only when you need it. If the controls are old, or there is no room thermostat, SEAI pays a €700 grant towards upgraded heating controls for homes built and occupied before 2011. You must use an SEAI-registered contractor and have the grant approved before any work starts. You cannot get it if you have claimed or are applying for a heat pump grant (SEAI heating controls grant).

Find the boiler's reset button and the oil shut-off valve too, so you know where they are. Our oil boiler not working guide explains how many times it is safe to reset it.

Help with heating costs

If you get a qualifying social welfare payment, or you are 66 or over and pass a means test, you may get Fuel Allowance. It is €38 a week now and rises to €43 a week from January 2027, paid during the heating season (Citizens Information: Fuel Allowance). It is paid in cash, so you can put it towards oil. A late claim normally starts from the date it is received, so claim when you move in. Our guide to heating oil grants and supports lists the rest.

Your first-week checklist

Find the tank and check its condition.
Read the oil level and note the tank size.
Confirm the fuel: kerosene or gas oil.
Check the delivery route, gate and fill cap.
Order oil if the tank is below about a quarter.
Get the boiler service records, or book a service.
Fit or test carbon monoxide alarms.
Learn the timer, thermostat, reset button and shut-off valve.
Check whether you qualify for Fuel Allowance or the heating controls grant.
Set a price alert so you can order when prices dip.

Common questions

How do I know how much oil is in the tank when I move in?

Look at the gauge on the tank, or a remote monitor if one is fitted. With no gauge, a clean dipstick through the fill cap gives a rough depth. If the reading looks wrong, assume you are low and order soon.

Does a new house with oil heating need a boiler service?

If you cannot get a service record from the last 12 months, book one. The NSAI advises a yearly service for oil boilers, and a technician can also confirm which fuel the boiler uses.

Is there a grant for heating controls on an oil boiler?

Yes. SEAI pays €700 towards upgraded heating controls for homes built and occupied before 2011. You must use an SEAI-registered contractor and have the grant approved before work starts. You cannot get it if you have claimed or are applying for a heat pump grant.

Who do I call if the carbon monoxide alarm goes off?

Turn off the boiler and any other fuel-burning appliance, get everyone outside into fresh air, and call 112 or 999 if anyone feels unwell. Do not use the boiler again until a qualified technician has checked it.

Next step

Compare heating oil prices from oil suppliers near you, or find an oil supplier that delivers to your address. To be told when prices fall, set up a price alert.