Boilermate 2000 - Low water flow

[WobblyDog]

I wonder if anyone can help with a Boilermate 2000 “low hot water flow” problem?

The Boilermate is 8 years old and we are in a very hard water area. The system has always worked pretty well with what I would call a “good” flow of hot (and cold) water when running a bath or shower. Turning on another tap or flushing a toilet at the same time would diminish the flow slightly but not substantially.

Approximately 2 months ago our water flow suddenly reduced one morning. Our neighbours weren’t affected so I assume it is something to do with our system. I have (roughly) measured the flow at a bath mixer tap and it is 10L/min from hot, the same from cold and when both are turned on together, 11L/min. Pressure from a garden tap is about 2.3 bar.

I don’t have any “before” measurements but it is now taking ages to run a bath (25 mins) and if another shower is used or toilet flushed the flow reduces substantially. I have renewed the mains stopcock, just in case it was that.

In fact in one bathroom, flushing a toilet means that water virtually stops flowing from a sink mixer tap completely. House layout is three storeys, two bathrooms (with separate showers) and one shower room.

Hot water temperature is good and constant and from what I’ve read it seems to point to a scaled PHE on the Boilermate. What I’m hesitant about though is why this would affect the cold water supply (or maybe that's a red herring).

Sorry for the long first post but hopefully someone can shed some light!

Thanks.

 

[ismellgas]

have you noticed if there has been any work getting done in the area? this happend to me, they were working on the water mains and then one day i got a bit of grit out the tap then the flow was terrible.

They came out and dug up the street and fitted a new toby for my house and still the problem was the exact same. I took the outside tap off and hit the mains a few times lol then it must have moved the dirt because the pressure was back to normal after that.

 

[mickyg]

whats the flow like from the kitchen/garden tap? ignore pressure, its flow that matters here.

 

[WobblyDog]

ISG - I'm not aware of any work being done but of course a blockage due to grit is possible - that was partly why I changed the internal stopcock. Not sure how I'd clear it though!

Mickyg - Kitchen tap is about 10L/min (cold) and garden tap is slightly better at about 11L/min.

The kitchen tap is a mixer and if I turn both hot and cold on I still get 10L/min (so similar to the rest of the house). As I mentioned, I don't have the "before" measurements but my impression would have been that the flow would have been almost double what I'm currently getting.

 

[mickyg]

well if its a lot less than it was it must be on the line into the house. Maybe there's a partcile filter inline? or a comination valve perhaps? Try turning your stop cock on and off, and follow the pipework from it and see what valves are on the way if any to the first outlet.