I've balancing my new CH - noticed the flow and return to the boiler
were virtually the same - and the auto bypass valve was set to minimum
(0.1 bar = 1m head water IIRC)

Closing it down to 0.4 bar has jumped the differential temperature - but
I suspect that's too high.

The Worcester manual says the pump can deliver 2m head for "21C
temperature rise" - nothing else about min flow rates or bypass pressure.

Any ideas? If I turn it to 0.2bar the flow temperature starts to creep up.

Now this may also suggest I have the lockshields all turned down too low
as well (I've opened 1/4 - 3/4 turn as a starting point).

On 11/11/2017 11:44, Tim Watts wrote:
I've balancing my new CH - noticed the flow and return to the boiler
were virtually the same - and the auto bypass valve was set to minimum
(0.1 bar = 1m head water IIRC)

Closing it down to 0.4 bar has jumped the differential temperature - but
I suspect that's too high.

The Worcester manual says the pump can deliver 2m head for "21C
temperature rise" - nothing else about min flow rates or bypass pressure.

Any ideas? If I turn it to 0.2bar the flow temperature starts to creep up.

Now this may also suggest I have the lockshields all turned down too low
as well (I've opened 1/4 - 3/4 turn as a starting point).


I have mine set pretty high - based on the assumption that I only want
it to do anything when nearly all the TRVs are closed off. A highish
differential temperature should keep condensing efficiency up as well.

--
Cheers,

John.

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

On 11/11/17 16:59, John Rumm wrote:
On 11/11/2017 11:44, Tim Watts wrote:
I've balancing my new CH - noticed the flow and return to the boiler
were virtually the same - and the auto bypass valve was set to minimum
(0.1 bar = 1m head water IIRC)

Closing it down to 0.4 bar has jumped the differential temperature - but
I suspect that's too high.

The Worcester manual says the pump can deliver 2m head for "21C
temperature rise" - nothing else about min flow rates or bypass pressure.

Any ideas? If I turn it to 0.2bar the flow temperature starts to creep
up.

Now this may also suggest I have the lockshields all turned down too low
as well (I've opened 1/4 - 3/4 turn as a starting point).


I have mine set pretty high - based on the assumption that I only want
it to do anything when nearly all the TRVs are closed off. A highish
differential temperature should keep condensing efficiency up as well.


Thanks John.

After balancing round 1 (a differential thermometer with 2 pipe clamps
certainly makes this quicker!), I have 10-12 across all rads more or
less at a flow to rad of 56C (boiler indicates more like 65C internal).

Fiddling with the bypass, it seems to start shunting big time at a bit
under 0.4bar - so I have set it a smidge over.

The plan is now to turn the boiler down to about 55C flow - I have
oversized the rads as far as possible with a low flow temperature (and
spare in a really cold winter) in mind.

Think I'll have to go around one more time in a couple of weeks.

Next problem - it's bloody hot upstairs and there are no radiators.

But there is about 50-70m of exposed pipework!!!

It's been quite tightly run (linked Talon clips) and I cannot get 13mm
thick insulation on it. So I'm off to peruse the Internet for either
some thinner tube, or I'll have to box it in (and be damned if the flow
heats the return a bit).

Overall - very happy. I have boiled everyone half to death running it
flat out all day. That is very nice - this house has never been this warm

On 11/11/2017 18:31, Tim Watts wrote:

Overall - very happy. I have boiled everyone half to death running it
flat out all day. That is very nice - this house has never been this
warm

Yup its surprising how you notice heat after a long spell without!

I grew up in place that did not have CH until I was about 17ish.

Getting up on a winter's morning to go to college was a well honed
routine - kettle would boil on a time switch. Chuck water in mug left
waiting from the night before with coffee and milk in it, and turn on
the gas fire in bedroom, before leaping back into bed. Drink coffee and
wait for room to become slightly habitable while marvelling at the
frozen condensation on the inside of the windows!

Then one day I came back up in the evening, and the installers had the
new CH fired up, and the place was warm in winter for the first time ever!


--
Cheers,

John.

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

On 12/11/17 03:46, John Rumm wrote:
On 11/11/2017 18:31, Tim Watts wrote:

Overall - very happy. I have boiled everyone half to death running it
flat out all day. That is very nice - this house has never been this
warm

Yup its surprising how you notice heat after a long spell without!

I grew up in place that did not have CH until I was about 17ish.

Getting up on a winter's morning to go to college was a well honed
routine - kettle would boil on a time switch. Chuck water in mug left
waiting from the night before with coffee and milk in it, and turn on
the gas fire in bedroom, before leaping back into bed. Drink coffee and
wait for room to become slightly habitable while marvelling at the
frozen condensation on the inside of the windows!

Sounds like my bedroom in Reading, rented off an old polish bloke:

3kW fan heater on timeswitch. Coin meter ran out and I reckon the dT/dt
was about 1C/min!

Then one day I came back up in the evening, and the installers had the
new CH fired up, and the place was warm in winter for the first time ever!

On an aside:

Very pleased that my calculations seem to have borne out.

This is my spreadsheet:

https://drive.google.com/open?id=1fW...xZKXpMbXX-PTdk

I tried to design the biggest radiators in that I could, without taking
up excessive space. It was nice to have a clean sheet... PS the rad
prices were less via the plumber's discount and over half of the costs
were labour, so in the grand scheme of things not too bad.

Today, Heat Genius showed the kitchen/dining room (a difficult room to
heat - large, 2 big bay windows, no door to side lobby) went from

18.4C at 6am to
20.5C at 7am

with a *flow* temperature (external to boiler) of around 55C - that
would be the green column H on the sheet, delta-T=30K

Sadly the WB boilers do not have a simple weather compensation option
(they want you to use their smart programmer to get that and that
doesn't work with an external programmer) - so we're pretty much in the
land of twiddling the knob each month.

However, I'm hoping to reduce that to a simple guide on the boiler -
Novemeber - position 4, January - 5 or 6, or something like that...

On Sat, 11 Nov 2017 16:59:53 +0000, John Rumm
wrote:

On 11/11/2017 11:44, Tim Watts wrote:
I've balancing my new CH - noticed the flow and return to the boiler
were virtually the same - and the auto bypass valve was set to minimum
(0.1 bar = 1m head water IIRC)

Closing it down to 0.4 bar has jumped the differential temperature - but
I suspect that's too high.

The Worcester manual says the pump can deliver 2m head for "21C
temperature rise" - nothing else about min flow rates or bypass pressure.

Any ideas? If I turn it to 0.2bar the flow temperature starts to creep up.

Now this may also suggest I have the lockshields all turned down too low
as well (I've opened 1/4 - 3/4 turn as a starting point).


I have mine set pretty high - based on the assumption that I only want
it to do anything when nearly all the TRVs are closed off. A highish
differential temperature should keep condensing efficiency up as well.

Never actually having CH of my own [1] and only dabbling with other
peoples when helping them out, I am not up to speed on all the rules
re 'balancing' the system, especially on something like a combi /
sealed system.

I have a question / interest though because I was round my mates the
other day when they had the plumbers in because they didn't have any
hot water.

I had previously been told they had the gas boiler AND immersion on
because there were 4 of them showering every morning and the hw would
run out otherwise?

Anyway, I while back (a couple of years possibly) I had helped them
(over the phone) conclude that the immersion had probably gone as it
tripped the ELCB in the CU when you turned it on and I thought it had
been replaced (but it may have and had gone again)?

Anyroadup, the plumbers this time had previously replaced a motorised
valve (apparently, a couple of weeks earlier) and they thought it had
gone again (faulty) but then found a valve marked up 'Balance, do not
touch' that they had been completely turned off and opening it, seemed
to have fixed the problem?

Now the only time I was aware of a bypass was in the two way motorised
valves where when both were off you could potentially short out the
boiler so a 15mm pipe was placed in parallel with the HW cylinder and
before the mv to ensure there was always a path back to the boiler (or
somesuch)?

So, my question is 'could it be possible that a 'balance valve' is
likely to be (nearly) fully closed and for it to be right' please? I'm
asking in case the plumber doing what they did is not a real solution
and it will cause issues further down the line?

FWIW they have a fairly big HW cylinder and a mix of UF and
conventional radiator CH.

Cheers, T i m

[1] I did actually have the boiler and cylinder fitted here but then
my Uncle's coal fired floor standing CH failed so I took my stuff out
and fitted it (and some more rads) in his. In fact, because it was a
'low capacity' wall mounted boiler with a copper heat exchanger I also
fitted delayed stop relay to the pump and seemed to make the system
run very well (and never went wrong once in probably ~20 years). ;-)

On 12/11/17 11:17, T i m wrote:
On Sat, 11 Nov 2017 16:59:53 +0000, John Rumm
wrote:

On 11/11/2017 11:44, Tim Watts wrote:
I've balancing my new CH - noticed the flow and return to the boiler
were virtually the same - and the auto bypass valve was set to minimum
(0.1 bar = 1m head water IIRC)

Closing it down to 0.4 bar has jumped the differential temperature - but
I suspect that's too high.

The Worcester manual says the pump can deliver 2m head for "21C
temperature rise" - nothing else about min flow rates or bypass pressure.

Any ideas? If I turn it to 0.2bar the flow temperature starts to creep up.

Now this may also suggest I have the lockshields all turned down too low
as well (I've opened 1/4 - 3/4 turn as a starting point).


I have mine set pretty high - based on the assumption that I only want
it to do anything when nearly all the TRVs are closed off. A highish
differential temperature should keep condensing efficiency up as well.

Never actually having CH of my own [1] and only dabbling with other
peoples when helping them out, I am not up to speed on all the rules
re 'balancing' the system, especially on something like a combi /
sealed system.

I have a question / interest though because I was round my mates the
other day when they had the plumbers in because they didn't have any
hot water.

I had previously been told they had the gas boiler AND immersion on
because there were 4 of them showering every morning and the hw would
run out otherwise?

Anyway, I while back (a couple of years possibly) I had helped them
(over the phone) conclude that the immersion had probably gone as it
tripped the ELCB in the CU when you turned it on and I thought it had
been replaced (but it may have and had gone again)?

Anyroadup, the plumbers this time had previously replaced a motorised
valve (apparently, a couple of weeks earlier) and they thought it had
gone again (faulty) but then found a valve marked up 'Balance, do not
touch' that they had been completely turned off and opening it, seemed
to have fixed the problem?

Now the only time I was aware of a bypass was in the two way motorised
valves where when both were off you could potentially short out the
boiler so a 15mm pipe was placed in parallel with the HW cylinder and
before the mv to ensure there was always a path back to the boiler (or
somesuch)?

So, my question is 'could it be possible that a 'balance valve' is
likely to be (nearly) fully closed and for it to be right' please? I'm
asking in case the plumber doing what they did is not a real solution
and it will cause issues further down the line?

It could be a shunt. Normally you use a designated radiator. Or if you
don't want to (or don't trust it not to be fiddled with), you could do
as I did and put a pressure bypass in, which should only open to protect
the boiler pump.


FWIW they have a fairly big HW cylinder and a mix of UF and
conventional radiator CH.

Cheers, T i m

[1] I did actually have the boiler and cylinder fitted here but then
my Uncle's coal fired floor standing CH failed so I took my stuff out
and fitted it (and some more rads) in his. In fact, because it was a
'low capacity' wall mounted boiler with a copper heat exchanger I also
fitted delayed stop relay to the pump and seemed to make the system
run very well (and never went wrong once in probably ~20 years). ;-)

On Sun, 12 Nov 2017 12:41:34 +0000, Tim Watts
wrote:

snip

Anyroadup, the plumbers this time had previously replaced a motorised
valve (apparently, a couple of weeks earlier) and they thought it had
gone again (faulty) but then found a valve marked up 'Balance, do not
touch' that they had been completely turned off and opening it, seemed
to have fixed the problem?

Now the only time I was aware of a bypass was in the two way motorised
valves where when both were off you could potentially short out the
boiler so a 15mm pipe was placed in parallel with the HW cylinder and
before the mv to ensure there was always a path back to the boiler (or
somesuch)?

So, my question is 'could it be possible that a 'balance valve' is
likely to be (nearly) fully closed and for it to be right' please? I'm
asking in case the plumber doing what they did is not a real solution
and it will cause issues further down the line?

It could be a shunt.

As I describe above (but with some control)?

Normally you use a designated radiator.

So this would be on all the time, no stat-valve etc?

Or if you
don't want to (or don't trust it not to be fiddled with), you could do
as I did and put a pressure bypass in, which should only open to protect
the boiler pump.

Ah, that makes more sense and as you eluded to above, less chance of
being 'fiddled with'.

It will be interesting to see how it all went on Friday (when the
plumbers were due back to replace both motorised valves) and whilst
they were there the other day I overheard talk of 'one of the
motorised valves not being moveable by hand' ... but are they all (as
they could have been different makes / designs)?

Cheers, T i m

On 12/11/17 13:05, T i m wrote:
On Sun, 12 Nov 2017 12:41:34 +0000, Tim Watts


Normally you use a designated radiator.

So this would be on all the time, no stat-valve etc?

Yes.

And with lockshield valves both ends so normal users don't fiddle.

Or if you
don't want to (or don't trust it not to be fiddled with), you could do
as I did and put a pressure bypass in, which should only open to protect
the boiler pump.

Ah, that makes more sense and as you eluded to above, less chance of
being 'fiddled with'.

It will be interesting to see how it all went on Friday (when the
plumbers were due back to replace both motorised valves) and whilst
they were there the other day I overheard talk of 'one of the
motorised valves not being moveable by hand' ... but are they all (as
they could have been different makes / designs)?

Usually they have an override lever that can be pushed and dropped into
a locking slot, for when the motor fails.