The Natural Philosopher wrote:
System Description
==================


Mains pressurised DHW tank, fed via an ion exchange water softener.
heated by immersion and oil CH system boiler.

May have been messed aroound with by ex wife's 'friends' when I wasn't
there for last 4 years. Everything else has been...

Flow rate on even cold water mains (not via softener) seems less than I
remember.

Problem Description
===================

When filling the bath, after about 5 minutes/50 litres the flow starts
to tail off. Opening the tap restores it, but not fully. It deteriorates
to a trickle eventually.

I have not checked other hot taps yet when this happens..

I have checked that all stopcocks are on full as far as I can.

===================

All I can envisage is that flow is restricted somewhere and there is
some kind of a pressure vessel downstream of that somewhat larger than
the 'bubble' in the hot water tank, in play.

Any ideas?



Any slim chance that some foreign body has got into the pipe work?

I have come across something like that where the object was drawn by the
flow until it got to a constriction, in my a case a pipe joint and stems
the flow. The user gives up and meanwhile the object drifts back by gravity
down the pipe work especially if was at the top of a vertical run.

My situation was finding out why a pub lager tap stopped flowing and a
small sliver of plastic from the disposable keg top that protects the
outlet in transit had broken off and was small enough to get through the
keg coupling.

GH

On 09/01/2019 09:22, Marland wrote:
The Natural Philosopher wrote:
System Description
==================


Mains pressurised DHW tank, fed via an ion exchange water softener.
heated by immersion and oil CH system boiler.

May have been messed aroound with by ex wife's 'friends' when I wasn't
there for last 4 years. Everything else has been...

Flow rate on even cold water mains (not via softener) seems less than I
remember.

Problem Description
===================

When filling the bath, after about 5 minutes/50 litres the flow starts
to tail off. Opening the tap restores it, but not fully. It deteriorates
to a trickle eventually.

I have not checked other hot taps yet when this happens..

I have checked that all stopcocks are on full as far as I can.

===================

All I can envisage is that flow is restricted somewhere and there is
some kind of a pressure vessel downstream of that somewhat larger than
the 'bubble' in the hot water tank, in play.

Any ideas?



Any slim chance that some foreign body has got into the pipe work?

I have come across something like that where the object was drawn by the
flow until it got to a constriction, in my a case a pipe joint and stems
the flow. The user gives up and meanwhile the object drifts back by gravity
down the pipe work especially if was at the top of a vertical run.

My situation was finding out why a pub lager tap stopped flowing and a
small sliver of plastic from the disposable keg top that protects the
outlet in transit had broken off and was small enough to get through the
keg coupling.


Another interesting possibility

I am still checking out obvious mistakes..


GH



--
"First, find out who are the people you can not criticise. They are your
oppressors."
- George Orwell

On 09/01/2019 11:00, The Natural Philosopher wrote:
On 09/01/2019 09:22, Marland wrote:
The Natural Philosopher wrote:
System Description
==================


Mains pressurised DHW tank, fed via an ion exchange water softener.
heated by immersion and oil CH system boiler.

May have been messed aroound with by ex wife's 'friends' when I wasn't
there for last 4 years. Everything else has been...

Flow rate on even cold water mains (not via softener) seems less than I
remember.

Problem Description
===================

When filling the bath, after about 5 minutes/50 litres the flow starts
to tail off. Opening the tap restores it, but not fully. It deteriorates
to a trickle eventually.

I have not checked other hot taps yet when this happens..

I have checked that all stopcocks are on full as far as I can.

===================

All I can envisage is that flow is restricted somewhere and there is
some kind of a pressure vessel downstream of that somewhat larger than
the 'bubble' in the hot water tank, in play.

Any ideas?



Any slim chance that some foreign body has got into the pipe work?

I have come across something like that where the object was drawn by the
flow until it got to a constriction, in my a case a pipe joint and stems
the flow. The user gives up and meanwhile the object drifts back by
gravity
Â* down the pipe work especially if was at the top of a vertical run.

My situation was finding out why a pub lager tap stopped flowing and a
small sliver of plastic from the disposable keg top that protects the
outlet in transit had broken off and was small enough to get through the
keg coupling.


Another interesting possibility

I am still checking out obvious mistakes..

The combinations of what happens at cold taps, other hot taps, before
and after the cylinder PRV etc will probably identify the place to look
first.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Wednesday, 9 January 2019 09:22:49 UTC, Marland wrote:
The Natural Philosopher wrote:


Any ideas?



Any slim chance that some foreign body has got into the pipe work?

A good reason to vote Brexit ;-)