I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)
(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this
(4) move and/or replace rads .
(5) Close bleed valves ,Close drain tap,feed system with Sentinel
using the installed filling point ,open water valve and open filling
loop to around 2 Bar
(6) Open bleed valves to expel air while watching water pressure and
open filling loop if required . Continue doing this until all air is
expelled .
(7) switch power on and fire up boiler ,checking for any further
necessary bleeding .

wrote in message
...
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)
(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this
(4) move and/or replace rads .
(5) Close bleed valves ,Close drain tap,feed system with Sentinel
using the installed filling point ,open water valve and open filling
loop to around 2 Bar
(6) Open bleed valves to expel air while watching water pressure and
open filling loop if required . Continue doing this until all air is
expelled .
(7) switch power on and fire up boiler ,checking for any further
necessary bleeding .


I have recently installed some TRVs and did what you mention above. But
before i topped up the system i ran some water through (opened the water
valve for a while) to clean through the system. As there was no installed
filling point for the Inhibitor i just fed it through the top of one of the
rads upstairs using some tubing. Good luck!

Tom

In an earlier contribution to this discussion,
wrote:

I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.

Yes.

(2) switch off water supply feeding boiler ( is this necessary ?)

Not necessary.

(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this

You don't need to drain the whole system. Turn off *both* valves[1] [2] on
any radiators you are not touching, to keep then full during the operation.
You'll then only need to drain the pipework - and won't need so much new
inhibitor (assuming you have some already!)

(4) move and/or replace rads .

Yes

(5) Close bleed valves ,Close drain tap,feed system with Sentinel
using the installed filling point ,open water valve and open filling
loop to around 2 Bar

There are various ways of adding inhibitor. I made a device to pour it into
the top of an empty radiator after the blank plug had been removed.

(6) Open bleed valves to expel air while watching water pressure and
open filling loop if required . Continue doing this until all air is
expelled .

You may need to top up via the filling loop several times.

(7) switch power on and fire up boiler ,checking for any further
necessary bleeding .

That's about it!

[1] Make a note of how many turns it requires to close each lockshield valve
so that you can restore them to the same position.

[2] If TRVs are fitted, remove the heads and screw on the supplied
decorating caps to make sure that the valves stay closed however cold it
gets.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

On Sun, 9 Nov 2008 21:05:29 -0000, "Roger Mills"
wrote:

In an earlier contribution to this discussion,
wrote:

I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.

Yes.

(2) switch off water supply feeding boiler ( is this necessary ?)

Not necessary.

(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this

You don't need to drain the whole system. Turn off *both* valves[1] [2] on
any radiators you are not touching, to keep then full during the operation.
You'll then only need to drain the pipework - and won't need so much new
inhibitor (assuming you have some already!)

(4) move and/or replace rads .

Yes

(5) Close bleed valves ,Close drain tap,feed system with Sentinel
using the installed filling point ,open water valve and open filling
loop to around 2 Bar

There are various ways of adding inhibitor. I made a device to pour it into
the top of an empty radiator after the blank plug had been removed.

(6) Open bleed valves to expel air while watching water pressure and
open filling loop if required . Continue doing this until all air is
expelled .

You may need to top up via the filling loop several times.

(7) switch power on and fire up boiler ,checking for any further
necessary bleeding .

That's about it!

[1] Make a note of how many turns it requires to close each lockshield valve
so that you can restore them to the same position.

[2] If TRVs are fitted, remove the heads and screw on the supplied
decorating caps to make sure that the valves stay closed however cold it
gets.

Thx for that .I pretty much got it right . I think I've got
decorators caps for the TRV's..they are all fairly new .

wrote:
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)

If you isolate the rads via the lockshield & TRV, then no. Use a blanking
cap on the TRV. If you are not cutting into the pipework then yes.

(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this

Close off every other rad using the lockshield & TRV, it reduces the amount
needing to be drained and makes bleeding easier. That way you are only
draining the pipework & rad you are dealing with.



--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On Sun, 09 Nov 2008 23:18:58 GMT, "The Medway Handyman"
wrote:

wrote:
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing and
would appreciate if you could point out anything I have missed or
don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)

If you isolate the rads via the lockshield & TRV, then no. Use a blanking
cap on the TRV. If you are not cutting into the pipework then yes.

Eh...That's confused me now ,especially that last part .

(3) Drain down system ( there is a drain tap under the floor beside
boiler),opening bleed valves to assist this

Close off every other rad using the lockshield & TRV, it reduces the amount
needing to be drained and makes bleeding easier. That way you are only
draining the pipework & rad you are dealing with.

Yeah .I understand that part .Someone else said to do that as well.

wrote:
On Sun, 09 Nov 2008 23:18:58 GMT, "The Medway Handyman"
wrote:

wrote:
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing
and would appreciate if you could point out anything I have missed
or don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)

If you isolate the rads via the lockshield & TRV, then no. Use a
blanking cap on the TRV. If you are not cutting into the pipework
then yes.

Eh...That's confused me now ,especially that last part .

Sorry. If you just need to take the rad off for decorating for example,
then just isolate the rad, no need to turn off the supply. If you need to
replace the rad with a larger/smaller one, then you would need to switch off
the water supply, as you would be cutting the pipes.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On Sun, 09 Nov 2008 23:51:24 GMT, "The Medway Handyman"
wrote:

wrote:
On Sun, 09 Nov 2008 23:18:58 GMT, "The Medway Handyman"
wrote:

wrote:
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move or
replace a rad or two. I know it's not the ideal time of year to be
doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing
and would appreciate if you could point out anything I have missed
or don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)

If you isolate the rads via the lockshield & TRV, then no. Use a
blanking cap on the TRV. If you are not cutting into the pipework
then yes.

Eh...That's confused me now ,especially that last part .

Sorry. If you just need to take the rad off for decorating for example,
then just isolate the rad, no need to turn off the supply. If you need to
replace the rad with a larger/smaller one, then you would need to switch off
the water supply, as you would be cutting the pipes.

Ok.....but does the water supply not go via the filling loop so if it
is closed then does that not mean it makes no difference ....not that
it's a problem closing the water valve anyway .

In an earlier contribution to this discussion,
The Medway Handyman wrote:


Sorry. If you just need to take the rad off for decorating for
example, then just isolate the rad, no need to turn off the supply. If you
need to replace the rad with a larger/smaller one, then you
would need to switch off the water supply, as you would be cutting
the pipes.

I answered 'no' to that one - taking it to refer to the cold supply for the
DHW. With a combi, that surely doesn't mix with the heating circuit, but is
separated by a heat exchanger?
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

wrote:
On Sun, 09 Nov 2008 23:51:24 GMT, "The Medway Handyman"
wrote:

wrote:
On Sun, 09 Nov 2008 23:18:58 GMT, "The Medway Handyman"
wrote:

wrote:
I have replaced Ch rads etc etc on my old system but now I have a
sealed system ( Combi) and I want to sometime in the future move
or replace a rad or two. I know it's not the ideal time of year
to be doing this but I need to do it when the urge takes me .
I want to confirm what I need to do so here's what I intend doing
and would appreciate if you could point out anything I have missed
or don't need to do .

(1) switch off power to boiler.
(2) switch off water supply feeding boiler ( is this necessary ?)

If you isolate the rads via the lockshield & TRV, then no. Use a
blanking cap on the TRV. If you are not cutting into the pipework
then yes.

Eh...That's confused me now ,especially that last part .

Sorry. If you just need to take the rad off for decorating for
example, then just isolate the rad, no need to turn off the supply.
If you need to replace the rad with a larger/smaller one, then you
would need to switch off the water supply, as you would be cutting
the pipes.

Ok.....but does the water supply not go via the filling loop so if it
is closed then does that not mean it makes no difference ....not that
it's a problem closing the water valve anyway .

The filling loop will shut off the supply to the rads if thats what you are
asking.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk