Identifying central heating pipework.

[Loveplumbandgas]

I have a question about a job I am currently doing which is causing a few problems at the moment, a job I am at where they are bit by bit renovating a fairly large house, it has had its boiler removed (Vaillant not that its relevant) and there are 4 cut pipes in the ceiling space (no gas this has been removed and capped further back) which have been cut and left uncapped by someone without leaving any indication of which one was flow/return, they are currently doing the floorboards and I am due to go back there next week but I need to identify which pipes are which for the system which is sealed with an external pump and zone valves on one of the top floors in a cupboard. Does anyone know how I can quickly and easily identify these as none of the pipework is visible other than the metre of each I can see and the guy who ripped it out is not around to be asked.

 

[townfanjon]

Individually put a Bit of tissue in the end and blow hard , mark them as you go

 

[ShaunCorbs]

think by what your saying system boiler was installed

 

[Loveplumbandgas]

Its not about the boiler its about the pipework, I need to find out which pipes are flow and which are return.

 

[SimonG]

As Jon said above, bit of tissue or cap all ends bar one and blow.