Replacing central heating plastic pipes

[nick83]

Just trying to obtain some advice.I need to peplace the plastic pipe work which is under the screed in living room,as despite chemicals and powerflushing they are still blocked.
They seem to be clad in the grey foam type insulation,from what I can see,with copper rad tails.Has anyone tried 'pulling' a length out and re-threading a new one? rather than cutting up the whole floor.Its not floor coverings im bothered about just the mess and labour.Obviously as I don't know position of pipes there could be bits joined on --hence my next question
Also has anyone ever used an infrared camera to get an idea about pipe positions before cutting screed
many thanks

 

[SimonG]

Pipe above and drop to rads.

 

[Gasinspect]

get second opinion. seems unlikely that blockage would be that severe. when powerflushing, did you isolate that section from the rest of the system? if you can isolate, Fernox and most manufacturers do a more severe cleaning product.
Have also used 6mm drain cleaning wire on some jobs to dislodge and break up a blockage, depends on access.
Sometimes blockage is just a thin crust where there is a tee to that section, which can be broken up. Have known a sharp tap with a block of wood to do the trick, again depends on whether you can find the branch tee that feeds that section.

Is it just underfloor heating loops, or are they pipes feeding radiators?

Thermal imaging camera would work, but only if if floor is colder and pipes are hotter, so of course you would have to get heat circulating in pipes first in order to show up!

 

[king of pipes]

Any pictures available please

 

[nick83]

get second opinion. seems unlikely that blockage would be that severe. when powerflushing, did you isolate that section from the rest of the system? if you can isolate, Fernox and most manufacturers do a more severe cleaning product.
Have also used 6mm drain cleaning wire on some jobs to dislodge and break up a blockage, depends on access.
Sometimes blockage is just a thin crust where there is a tee to that section, which can be broken up. Have known a sharp tap with a block of wood to do the trick, again depends on whether you can find the branch tee that feeds that section.

Is it just underfloor heating loops, or are they pipes feeding radiators?

Thermal imaging camera would work, but only if if floor is colder and pipes are hotter, so of course you would have to get heat circulating in pipes first in order to show up!

 

[nick83]

usual story.Only discovered best practice after the event!
I had thought aboput trying to thread one of those drain wires,i assume i would have to drain all system down in case there was a sudden water release.
when you say isolate the area do you mean turn all other working rads off
seems alot of powerflush companies claim it can unblock a heating pipe

 

[nick83]

Any pictures available please

do you mean of the layout of the rads?

 

[king of pipes]

Yes where the pipework comes from and goes to , i very much doubt you will be able to remove the pipes and replace them under the floor , it would be better to try removing the radiator and blasting the under ground pipes through with mains cold water replace the rad valves and flush through the the radiator before refitting if this fails then abandon the under ground pipework and repipe from above . Cheers kop