Watchman Alarm Tank Monitor

including VAT & FREE delivery to the UK

With all of the features of the standard WatchmanSonic PLUS the additional benefit of an alarm!

The revolutionary electronic measuring gauge which will set off an alarm at the receiver in the house when there is a dramatic drop in oil levels!


The WatchMan Sonic Alarmed 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 receiver, indicating that it's time to order more oil.


Watchman Sonic Alarm Facts

    • Audible alarm feature
    • Easy installation - one 32mm hole needed (most tanks already have one pre-drilled)
    • No wiring required
    • Plugs into any 13 amp mains socket
    • Suitable for steel or plastic tanks
    • Up to 200 metres line of sight range
    • Long Life Battery - guaranteed for at least 12 months (But estimated to last 3 years!)
    • Option of an audible setting sending out a buzzing tone when oil levels run low



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 liquid 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.

In the event of the oil level in the tank dropping at a rate that is not common for a domestic oil tank (more than 1.5cm a minute) the receiver will emit an audible alarm.



See how easy it is to install by watching the video below:


Please note: this product is only available for delivery within the UK Mainland and Northern Ireland. Delivery is usually between 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 Alarm?
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 Alarm. 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 Alarm 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 Alarm?
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 Alarm okay next to the microwave?
Yes, the Watchman Alarm will not interfere with the kitchen appliances.

Does my Watchman Alarm 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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