Hi,

I have an intermitant problem with my ideal response 120 combi
where when running the hot water after a few minutes :-

1 The hot water flow slows right down
2 The water then runs cold
3 I then turn of the tap, wait a few minutes. normal flow
and hot water return

what would cause this and what would reduce the flow rate?

many thanks

On Wed, 19 Mar 2008 22:44:51 +0000, Block wrote:

Hi,

I have an intermitant problem with my ideal response 120 combi where
when running the hot water after a few minutes :-

1 The hot water flow slows right down 2 The water then runs cold
3 I then turn of the tap, wait a few minutes. normal flow
and hot water return

what would cause this and what would reduce the flow rate?

many thanks

Very likely this is a *tap* problem. You open the tap a small way
(because you have good water pressure) and the DHW start to flow, the
boiler does it's stuff and the water and tap becomes hot.

The hot tap head expands and closes down the flow of DHW to the point
where the boiler cuts out...

All this might be aggravated by an insensitive DHW flow detector in the
boiler (I've not got a Response manual so can't remember or guess the
mechanism).




--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi

I trust it isn't preparing to depart this world. . . .http://
www.diyfaq.org.uk/humour.html

"Ed Sirett" wrote in message
...
On Wed, 19 Mar 2008 22:44:51 +0000, Block wrote:

Hi,

I have an intermitant problem with my ideal response 120 combi where
when running the hot water after a few minutes :-

1 The hot water flow slows right down 2 The water then runs cold
3 I then turn of the tap, wait a few minutes. normal flow
and hot water return

what would cause this and what would reduce the flow rate?

many thanks

Very likely this is a *tap* problem. You open the tap a small way
(because you have good water pressure) and the DHW start to flow, the
boiler does it's stuff and the water and tap becomes hot.

The hot tap head expands and closes down the flow of DHW to the point
where the boiler cuts out...

All this might be aggravated by an insensitive DHW flow detector in the
boiler (I've not got a Response manual so can't remember or guess the
mechanism).




--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html


Many thanks Ed,

Gives me something to go on should it become a nuisance.

On Thu, 20 Mar 2008 06:25:12 -0700, 1501 wrote:

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi

I trust it isn't preparing to depart this world. . . .http://
www.diyfaq.org.uk/humour.html

Search around on the archives and you'll know the score.
Keep boiler on high settting, all TRVs to max and control with wall
thermostat.
This boiler must not be allowed to condense.




--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

Ed Sirett wrote:
On Wed, 19 Mar 2008 22:44:51 +0000, Block wrote:

Hi,

I have an intermitant problem with my ideal response 120 combi where
when running the hot water after a few minutes :-

1 The hot water flow slows right down 2 The water then runs cold
3 I then turn of the tap, wait a few minutes. normal flow
and hot water return

what would cause this and what would reduce the flow rate?

many thanks

Very likely this is a *tap* problem. You open the tap a small way
(because you have good water pressure) and the DHW start to flow, the
boiler does it's stuff and the water and tap becomes hot.

The hot tap head expands and closes down the flow of DHW to the point
where the boiler cuts out...

All this might be aggravated by an insensitive DHW flow detector in the
boiler (I've not got a Response manual so can't remember or guess the
mechanism).





This has always been the case with my bathroom basin hot tap
since installing a new W/B 28i .
My taps are cheap crap.

Arthur

"Ed Sirett" wrote in message
...
On Thu, 20 Mar 2008 06:25:12 -0700, 1501 wrote:

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi

I trust it isn't preparing to depart this world. . . .http://
www.diyfaq.org.uk/humour.html

Search around on the archives and you'll know the score.
Keep boiler on high settting, all TRVs to max and control with wall
thermostat.
This boiler must not be allowed to condense.




--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html


This problem happens with the shower and most
of the taps, could they all be at "fault" ?

On Sat, 22 Mar 2008 17:58:31 +0000, Block wrote:

"Ed Sirett" wrote in message
...
On Thu, 20 Mar 2008 06:25:12 -0700, 1501 wrote:

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi


snip problem about HW flow going cold after a short while


This problem happens with the shower and most of the taps, could they
all be at "fault" ?

Does anyone know if the Response 120 has a built-in store? (IIRC it
doesn't).

What's the cold water pressure and flow like?



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

"Ed Sirett" wrote in message
...
On Sat, 22 Mar 2008 17:58:31 +0000, Block wrote:

"Ed Sirett" wrote in message
...
On Thu, 20 Mar 2008 06:25:12 -0700, 1501 wrote:

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi


snip problem about HW flow going cold after a short while


This problem happens with the shower and most of the taps, could they
all be at "fault" ?

Does anyone know if the Response 120 has a built-in store? (IIRC it
doesn't).

What's the cold water pressure and flow like?



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html


It doesnt have a built in store and the cold water pressure is strong,
flow seems good (sorry for lack of detail) havent actually measured any of
these.

thanks

"Ed Sirett" wrote in message
...

Does anyone know if the Response 120 has a built-in store?

No.

"Block" wrote in message
...

"Ed Sirett" wrote in message
...
On Sat, 22 Mar 2008 17:58:31 +0000, Block wrote:

"Ed Sirett" wrote in message
...
On Thu, 20 Mar 2008 06:25:12 -0700, 1501 wrote:

On 19 Mar, 22:44, "Block" wrote:
Hi,

I have an intermitant problem with my ideal response 120 combi

snip problem about HW flow going cold after a short while

This problem happens with the shower and most of the taps, could they
all be at "fault" ?

Does anyone know if the Response 120 has a built-in store? (IIRC it
doesn't).

What's the cold water pressure and flow like?

Does this dropping off of flow happen with the cold water too? If so, then
look at the main stop tap.

The Response has no 3-valve and the DHW is activated via a flow switch.

The heat exchanger may be blocked. When off, the pressure is high, then
stays high for awhile until the dynamic pressure falls off because of the
blockage. This boiler should always have a strainer to catch solids on the
cold water feed - as should all combis.