Condensate pipe into old decommissioned cw cistern?

[Just_back_from_the_pub]

About a year or so ago my neighbours in the flat downstairs had their old system boiler replaced with a Worcester Bosch combi - unsure as to which model. They are currently away on holiday and I thought this would be a good time to remove their old cold water cistern to liberate a bit of space in their loft. I would have expected this to be carried out by the contractors as part of their work but it was not the case. The mains supply pipe which ran to the cistern has been redirected and now connects to a length of 22mm which runs to the boiler. Irritatingly this pipe runs in a position that would prevent access to the loft once the cistern is removed, so I will need to re-run this length of pipe. Though the old distribution pipes and overflow have been removed and capped off as one would expect I remain concerned about one other item. A grey plastic overflow pipe seems to run about four metres (through an inaccessible section of the loft) towards the boiler. The other end (elbowed) hangs over into the cistern. I wondered initially if this would have been used to siphon out the water that would have remained after draining from the distribution pipes, thus facilitating cistern removal if that is what was intended. Now I am worried that this might be the condensate pipe? There is no connection to the kitchen waste (other than the washing machine and dishwasher). Surely, then, the cp should be connected to a soilstack? Admittedly, though, the nearest soilstack is some distance from the point on the exterior wall where the boiler has been sited.

If this is the condensate pipe is such a connection acceptable or should it have been resited? Also is it dangerous to the occupants that a seemingly toxic substance runs into a decommissioned cw cistern? I should stress that the cistern, currently, is absolutely dry though this is not surprising as the boiler would not have been used for a couple of weeks.

 

[giblets]

If the cistern is dry then the pipe in question won't be the condensate pipe as this discharges liquid at regular intervals whilst the boiler is working. Can you not trace the boiler end of the pipe?

 

[Just_back_from_the_pub]

If the cistern is dry then the pipe in question won't be the condensate pipe as this discharges liquid at regular intervals whilst the boiler is working. Can you not trace the boiler end of the pipe?

I can trace the pipes from the boiler only to a limited extent because this area has been boxed in. I can see that the leftmost pipe is white plastic but am unable to determine where it runs after this.