Pressure drop on test of new install

[Wayne soppitt]

Hello guys , girls .
Can you please advise on the following.
Had a new water and heating system installed into a new build property and was all cross connected and put under pressure test . this happened Sunday the 14th of Jan , so been under test for a week now. The pressure was left at 5bar and has now gone down to 4.5 bar over the week period ,is this OK or does it indicate a small leak / drip in the system or is that normal for the pressure to drop that much.
Thanks for your help.
Sparky wayne

 

[Scott_D]

What's on test, just pipework?

 

[Wayne soppitt]

Just been 1st fixed so only pipework on test yes

 

[kozak1968]

Did you use plastic or copper pipework?

 

[Wayne soppitt]

Did you use plastic or copper pipework?

Majority plastic hep pipe and fittings just copper drops for outside taps

 

[kozak1968]

You will get a drop on plastic as the pipe expands. A week is too long for the test. The plastic pipe manufacturers specify a procedure for testing their pipework and its only about 20 minutes. I'm sure someone on here can elaborate on this.

 

[Wayne soppitt]

You will get a drop on plastic as the pipe expands. A week is too long for the test. The plastic pipe manufacturers specify a procedure for testing their pipework and its only about 20 minutes. I'm sure someone on here can elaborate on this.

Is the length of time for test likely to have any damaging effect on the pipework and connections?

 

[ShaunCorbs]

Did you purge all the air out ?

Also plastic suppliers normally recommend a water test pressure of around 10 bar for an hour max

 

[Wayne soppitt]

Did you purge all the air out ?

Also plastic suppliers normally recommend a water test pressure of around 10 bar for an hour max

The system was water filled , not sure if air was purged out as not the one to put it under test but would imagine it was.

 

[Gasmk1]

too many factors come into a long test temperature and bariometric pressure, need to be calculated

 

[Scott_D]

Inspect the joints
No wet patches and you should be fine