Leak detector

1. A leak detector for detecting leaked liquid from a liquid containing pipe in a plumbing system, the leak detector comprising:

a flexible and elongate fastener configured to fit around the liquid containing pipe to thereby attach the leak detector to the liquid containing pipe;

electrical circuitry;

a housing containing the electrical circuitry; and

a leak sensor comprised in at least one of the fastener and the housing, the leak sensor sensing liquid leaking from the liquid containing pipe, the electrical circuitry detecting a leak in dependence on an output from the leak sensor, wherein

the leak detector is configured such that the housing and the fastener are side by side in a longitudinal direction of the fastener whereby the housing and the fastener are abreast;

the electrical circuitry is supported on a flexible printed circuit board and the housing is flexible, whereby the housing and the electrical circuitry therein fit closely around the liquid containing pipe;

the fastener is constituted by at least one part of the flexible printed circuit board; and

a liquid sensing part of the leak sensor comprises two spaced apart electrically conducting elements, the two spaced apart electrically conducting elements formed on the at least one part of the flexible printed circuit board constituting the fastener.

2. The leak detector according to claim 1 , wherein a liquid sensing part of the leak sensor extends along the fastener.

3. The leak detector according to claim 2 , wherein the two spaced apart electrically conducting elements extend along the fastener, electrical conduction between the two spaced apart electrically conducting elements in the presence of leaked liquid causing the electrical circuitry to detect a leak.

4. The leak detector according to claim 3 , wherein each of the two spaced apart electrically conducting elements follows a tortuous path along the fastener.

5. The leak detector according to claim 1 , wherein the housing is constituted by a mass of material disposed over the flexible printed circuit board, the mass of material encapsulating the electrical circuitry.

6. The leak detector according to claim 1 , wherein the electrical circuitry is supported on a first part of the flexible printed circuit board, the fastener is constituted by a second part of the flexible printed circuit board, the first part being disposed to a side of the second part in a direction orthogonal to a longitudinal direction of the fastener whereby the electrical circuitry is alongside the fastener.

7. The leak detector according to claim 6 , wherein the first and second parts of the flexible printed circuit board are joined by a bridging portion, the bridging portion being constituted by the flexible printed circuit board.

8. The leak detector according to claim 1 , wherein the electrical circuitry is configured to transmit a leak detected signal to a remote location, transmission of a leak detected signal comprising at least one of an email and a Short Message Service (SMS) message.

9. The leak detector according to claim 1 , wherein the leak detector is of a size and weight that it is readily gripped in and moved by one hand.

10. The leak detector according to claim 1 , wherein the leak detector comprises a wireless transceiver, the leak detector comprising electrical circuitry configured to extract electrical power from a wireless signal received by the wireless transceiver.

11. The leak detector according to claim 1 , wherein the fastener comprises a retaining arrangement which is configured to hold spaced apart locations on the fastener together whereby the leak detector is held in place around a pipe.

12. The leak detector according to claim 1 , wherein the liquid containing pipe is a pipe for supplying or draining water in the plumbing system.