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Watchman Sonic Tank Monitor

including VAT & FREE delivery to the UK

Monitor your oil heating levels from the comfort of your own home, giving you peace of mind that you won’t run out.

The Watchman Sonic uses ultrasonic level measurement techniques to continuously measure the level of oil in your tank. This is then sent wirelessly from a transmitter on top of the tank to the receiver which is plugged into a mains wall socket inside your home.

When the oil level falls below 10%, a fuel dispensing pump symbol appears on the Watchman Sonic  receiver, indicating that it's time to order more oil.

Watchman Sonic Oil Tank Monitor Facts

  • Easy installation - one 32mm hole needed (most tanks already have one pre-drilled)
  • No wiring required
  • Plugs into any 13 amp mains socket
  • Up to 200 metres line of sight range
  • When the oil level falls below 10% the fuel dispensing pump symbol appears, indicating that it's time to order more oil.
  • When the oil level falls below 5% an LED light starts to flash, indicating that it's crital to order oil.



The transmitter sits on top of the tank and using ultrasonic level measurement techniques, constantly measures the level of oil in the tank.

It then transmits that information to the receiver which is plugged into an electric wall socket, located in a convenient place within the house.

The oil level is displayed on a LCD screen on the receiver. The householder can monitor the level of oil in their tank from inside their home.

When the level of oil in the tank gets below 10%, the fuel dispensing pump symbol appears, indicating to the householder that it is time to order some more oil.

This product is only available for delivery within the UK Mainland / Northern Ireland and will be with you in approx. 2 - 3 working days.


Frequently asked questions:


I already have a Watchman fitted to my tank; do I need to drill a new hole in my tank to fit the Watchman Sonic?
No, the Watchman Sonic will fit into the same hole, please remember to remove all parts of the original watchman from the tank prior to fitting the Watchman Sonic. The recommended hole size is 32mm but if your existing hole is slightly bigger its ok, but 38mm would be the maximum hole size otherwise the screw holes would be too close to the hole.

Do we need to twin the Watchman Sonic after a power cut?
No, however, there have been some cases where the re-twinning process has been required.

Can I have two receiver plugs for my Watchman Sonic?
Yes you can. As long as they are both correctly set and twinned to the transmitter, you can have multiple receiver plugs reading from one transmitter.

Is my Watchman Sonic okay next to the microwave?
Yes, the Watchman Sonic will not interfere with the kitchen appliances.

Does my Watchman Sonic receiver plug need to see the transmitter on the tank?
No, the distance between the transmitter and the receiver plug is 200m maximum.

What does ‘line of sight’ mean?
The distance between the transmitter and receiver plug should be clear from obstacles such as forest/steel buildings – still within the 200m range.

What is the warranty period?
Our product comes with 12 months warranty from date of purchase.

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