These test can be done by BT or broadband supplier.
- Copper line test, to check the quality of the phone line.
- ADSL noise test, to check the quality of an ADSL signal.
Dial 151 for home repairs helpline e.g. if hear noise on the line can ask BT to run copper line test. It’s probably best you run a “quiet line” test yourself beforehand. See below.
Voice vs ADSL
151 people will only test for voice and if there’s a problem will report it to BT OpenReach (who are responsible for the line).
For broadband, it’s up to the broadband supplier to test and report any problems to BT OpenReach.
A voice test can come back as passed when a broadband test is failing, and presumably vice versa.
How to run a “quiet line” aka noise test
BT only guarantees service up to the point that the line enters the house. The cost of fixing any faults in the internal wiring/equipment will be chargeable. So, to test the external line you can run a quiet line test from the test socket.
Locate the master socket - the one into which the external phone cable feeds, with a front panel that splits 2/3 of the way up. Undo the two small screws and remove the panel (this will disconnect the phone). The test socket is located behind the panel. Plug a phone in and dial 17070, choosing option 2 for the quiet line test.