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View Full Version : whats chances of replacing a 7m under ground cable run in 20mm conduit?



wozzzzza
6th September 2023, 04:24 PM
i have to replace cabling in a 9m long under ground cable run that has 5 cables in it and the conduit is 20mm orange stuff.
what are the chances of being able to do this successfully after it being there a few decades?? and possibly full of mud and dirt etc..

droog
6th September 2023, 07:42 PM
What size are the 5 cables ?
Replace 1 or all 5 cables ?
How many bends, angles, small or large radius ?

wozzzzza
6th September 2023, 08:06 PM
What size are the 5 cables ?
Replace 1 or all 5 cables ?
How many bends, angles, small or large radius ?
look like combination of 2.5 and 1.5mm building cable no sheath.
will replace all.
no idea if the bends are that or elbows or what angles are under there. thinking just giving them one big pull, they are fuked any way.

droog
6th September 2023, 09:11 PM
look like combination of 2.5 and 1.5mm building cable no sheath.
will replace all.
no idea if the bends are that or elbows or what angles are under there. thinking just giving them one big pull, they are fuked any way.

Disconnect all services, and see if it will move, i suspect no.
Then
Flush with a hose to get rid of debris until it runs clean.
Blow any water out of the duct with compressed air.
Add cable lubricant at each end then see if it will move.

Remember to attach a cord so if it does move you can pull new services through.

wozzzzza
6th September 2023, 09:21 PM
cool, worth a try, wont loose anything if it doesn't work.
probably stick a snake down it first to tie cable to to pull through with l00b

wozzzzza
15th September 2023, 05:31 PM
i tried pulling them out and they wont budge, so what do i do with hose? just stick it in the end of the conduit and turn it on? water will back up and spray out wont it? i cant see it going through??

havabeer69
16th September 2023, 06:18 PM
so start with a blower vac thing... even the little job site ones. blow air in it and feel at the other other end if air is moving... at least you'll know its clear.

droog
16th September 2023, 07:34 PM
i tried pulling them out and they wont budge, so what do i do with hose? just stick it in the end of the conduit and turn it on? water will back up and spray out wont it? i cant see it going through??

If the water won’t go through then it proves the conduit is blocked…
If you get some flow through it will flush any debris out, but if it is totally blocked then get your shovel out.

wozzzzza
16th September 2023, 10:23 PM
If the water won’t go through then it proves the conduit is blocked…
If you get some flow through it will flush any debris out, but if it is totally blocked then get your shovel out.
might give it a go tomorrow attach a hose to it somehow

so start with a blower vac thing... even the little job site ones. blow air in it and feel at the other other end if air is moving... at least you'll know its clear.
ive tried compressed air and nothing.

russ57
22nd September 2023, 10:45 PM
It may have been sealed to prevent water ingress.
Under my house one day, heard water running.

The underground power conduit was running like a hose.

Apparently not sealed at the street pit.
Complained to ausnet who advised it was my installer at fault. I then explained that the underground service had been installed by the sec when hv transmission lines were built and services undergrounded.
Came home from holidays to find a new pit installed and no more gusher under the house.

wozzzzza
25th October 2023, 11:35 PM
ended up spending 6 hours digging up the drive way to run new conduit, cable is now in and all working fine.

ErrolFlynn
26th October 2023, 07:23 AM
Did you get to the old conduit by any chance? Just wondering if you did, and removed it, and found out why you had trouble with it.

wozzzzza
26th October 2023, 10:12 AM
Did you get to the old conduit by any chance? Just wondering if you did, and removed it, and found out why you had trouble with it.
no, i think it goes another direction over there under concrete that looks like it was laid as part of the driveway where the council replaced the footpath and widened it 7 years ago and into our property a bit so i pulled up the pavers at end of where the concrete ended at end of driveway, about 30cm away from original conduit i predict.