Gravity Cold Water issue

[MickBrown]

Went to a house today with no cold water coming out of the upstairs taps, 3 taps in all. Hot water okay but poor pressure. In addition no cold water is coming out of the shower which is fed by a negative head pump with it's own seperate cold feed. The pump does not kick in even when selected to hot only. Checked the three outlets from the cold water storage tank, no sign of insulation getting into the tank and all the 3 outlets clear of debris. Put my aquavac on the cold taps but couldn't suck anything out.

The only thing I didn't try was disconnecting the cold inlet to the pump to see if there was any cold flow there, probably do that tomorrow.

Owners said that the bathroom was refurbished about a year ago and ever since they have very occasionally got an airlock on the cold but it has always cleared itself if they opened all cold taps.

It just seems weird that both the taps and the shower colds have stopped at the same time which are on seperate cold feeds from the tank.

Any ideas?

 

[townfanjon]

Nobody's turned a gate valve off anywhere, turned it back on and its broken internally

 

[MickBrown]

There has not been any tradesmen at the property, the only valves are in the loft so unlikely family. Plus it is 2 seperate cold supplies from the tank.

 

[snowhead]

Hosepipe on the non working tap(s) and push mains cold up into the tank.

 

[Riley]

I was going to say it just sounds like a stubborn airlock it’s probably the pump drawing off more water than can be replaced

 

[Burger]

You mentioned an airlock, check for horizontal pipes with a backfall and any passovers.

 

[MickBrown]

I was going to say it just sounds like a stubborn airlock it’s probably the pump drawing off more water than can be replaced

There are 2 large cold water tanks so unlikely to run out, but still a possibility.

 

[MickBrown]

You mentioned an airlock, check for horizontal pipes with a backfall and any passovers.

All pipework is under tiled floor.

 

[Burger]

All pipework is under tiled floor.

That would render it extremely difficult to check, but that could be where it is. Also check the ones in the loft where they exit the tank, could be some there, sometimes if there’s “play” in the pipes, they get pushed up.

 

[MickBrown]

All sorted. Found out the taps were connected to the pump as well so the air lock was in the pump. It's not fitted very well with cold inlet and both outlet pipes going up and over into the floor. No swept bends but copper with pushfit elbows and no air vents. It's all working now but suggested to the customer that the pipework be changed for swept bends and airvents put in at the top. Thanks for replies.