Frequently Asked Questions 

Q: How do I stop an oil leak?

A: On plastic tanks rub a bar of soap into the split.


Q: How do I reset my Apollo Gauge?

A: Please see this printable version of the instructions

Q: How do I reset my Watchman Gauge?


1. Switch the Watchman on and off. You will see a serial number           followed by a lower case R                    (stands for Reset)

2. Unscrew and remove the power tube wait for 2 minutes and then screw the power tube back                on.

   This should reboot the system

3. Within a few minutes the Watchman should display the level of oil in your tank.


What the Signs Mean:


Red Light Flashing - No Signal

Red Flashing Light - Tank Is Low on Fuel

Fluid level low together with “BAT LOW” - New Power Tube Needed

C Means connection fault replacement needed.


To Change the battery

1. Switch off Watchman display.

2. Unscrew your existing copper tube battery from the transmitter.

3. Pause for 5 Minutes.

4. Switch the Watchman display back on.

5. Fit the new copper tube battery.



Q: Where can I purchase batteries for my Watchman Gauge?

A: From us or from Sensor Systems.


Q: Where can I purchase batteries for my Apollo Gauge?

A: From a Jewellers or a good electrical goods store

     The battery number is 3V-CR2430



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