We're local, we're best, we're CPS.

Domestic 01953 713950

Commercial 01953 713540

Posted on: 30/03/2021

How long does heating oil last when the Watchman is flashing?

Watchman Flashing - how long will my heating oil last?might you be low?

With this latest Baltic Blast Mister C has been asked: How long does heating oil last when the watchman is flashing?

If your tank holds 1250 litres when full (max) then each bar is roughly 125 litres. A watchman will start to flash at 2 bars and this is just telling you that it’s time to order more fuel. If it has been installed correctly, 2 bars on a watchman is approximately 1/5 tank giving ample volume and time to reorder your oil and receive your delivery.

An average 3 bed house with a family will use 7 to 11 litres per day in autumn and mild winter and 11 to 28 litres per day in a harsh winter. So a day when a lot of heat and hot water is required could mean four times more kerosene is burnt than one when the need is light.

On our example tank we would estimate that 1/2 inch of oil is used in mild weather and more than 1 and possibly up to 2 inches per day if the weather is really harsh. You can use this as a guide if you use a stick to dip the tank or if you have a sight gauge.

Remember you are looking at how many inches are left and only the oil above the supply line is useable heating oil.

So these are good examples to get an idea of how much you have left and how long it might last BUT you can make changes to extend the oil you have remaining. By lowering your home temperature even 1 degree, having water only on if you actually need it, or turning off radiators in rooms you are not using, you can reduce your consumption and ensure you will not run out before the delivery man comes.

Please use this as a rough estimate only as not all storage is the same and households use fuel at different rates, but the main thing to identify is how much your oil tank holds when full and what is the level and thus how much it holds when the bars are start flashing.

Sonic Watchman Alarm

290 MisterC tupMister C has more answers to frequently asked questions here and helpful mini guides, such as how to replace the battery in your watchman or how to care for your heating oil tank, in our blog and news section.





Kingspan, the manufacturer of the Sonic Oil Level Sensor, have a new sensor installation and set up film on Youtube which walks you through the measurements needed to ensure your Watchman is operating correctly from day one.

CPS Fuels