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Default High return temperature on condensing boiler CH

Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.

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Default High return temperature on condensing boiler CH

Mark wrote:
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.


Does if have a flow temperature adjustment?
Was the house warm?
Have you got Thermostatic radiator valves?
What make and model is the boiler?
How many rads?

--
Cheers,

John.

/================================================== ===============\
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Default High return temperature on condensing boiler CH



"Mark" wrote in message
...
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?


Steam starts to condense at 100C.
Most of it will have condensed at 75C.




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Default High return temperature on condensing boiler CH

On Wed, 29 Oct 2008 09:53:01 +0000, John Rumm
wrote:

Mark wrote:
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.


Does if have a flow temperature adjustment?


Yes. It's set to "E", if that's any help.

Was the house warm?


I would say it was nearly warm.

Have you got Thermostatic radiator valves?


Yes (except in room with thermostat).

What make and model is the boiler?


W-B Hiflow 440

How many rads?


13.

--
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(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.
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Default High return temperature on condensing boiler CH

On Wed, 29 Oct 2008 10:39:13 -0000, "dennis@home"
wrote:



"Mark" wrote in message
.. .
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?


Steam starts to condense at 100C.
Most of it will have condensed at 75C.


I had heard that the flue gasses had to be below 55C to get the full
benefit of the condensing mode.

I read the following on several web sites:
"It is only possible for a condensing boiler to work to these very
high efficiencies if the flow and return pipework is also kept below
55°C."

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.
See http://improve-usenet.org



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Default High return temperature on condensing boiler CH



"Mark" wrote in message
...
On Wed, 29 Oct 2008 10:39:13 -0000, "dennis@home"
wrote:



"Mark" wrote in message
. ..
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?


Steam starts to condense at 100C.
Most of it will have condensed at 75C.


I had heard that the flue gasses had to be below 55C to get the full
benefit of the condensing mode.

I read the following on several web sites:
"It is only possible for a condensing boiler to work to these very
high efficiencies if the flow and return pipework is also kept below
55°C."


You can treat that with a pinch of salt.
Most of the waste heat saved is the latent heat of vapourisation.
If you condense most of the steam you get nearly all the heat back.
Cooling the flu gases down to 55-60C will only get you a very small amount
of energy back.
You could say that the return temp should be kept to 40c as then it is even
more efficient.
However it comes at a cost..
bigger radiators and making (and running) them wastes energy.

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Default High return temperature on condensing boiler CH


"Mark" wrote in message
...
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.


More info. What make model of boiler for starters and any info you have on
it.

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Default High return temperature on condensing boiler CH


"dennis@home" wrote in message
...


"Mark" wrote in message
...
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?


Steam starts to condense at 100C.


You got right, which is irrelevant to this point.

Most of it will have condensed at 75C.


This totally irrelevant too.

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Default High return temperature on condensing boiler CH


"dennis@home" wrote in message
...


"Mark" wrote in message
...
On Wed, 29 Oct 2008 10:39:13 -0000, "dennis@home"
wrote:



"Mark" wrote in message
...
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

Steam starts to condense at 100C.
Most of it will have condensed at 75C.


I had heard that the flue gasses had to be below 55C to get the full
benefit of the condensing mode.

I read the following on several web sites:
"It is only possible for a condensing boiler to work to these very
high efficiencies if the flow and return pipework is also kept below
55°C."


You can treat that with a pinch of salt.
Most of the waste heat saved is the latent heat of vapourisation.
If you condense most of the steam you get nearly all the heat back.
Cooling the flu gases down to 55-60C will only get you a very small amount
of energy back.
You could say that the return temp should be kept to 40c as then it is
even more efficient.
However it comes at a cost..
bigger radiators and making (and running) them wastes energy.


58C is the theoretical temperature in which flue gasses start to condense.
In doing so they give off latent heat. The return water temperature needs
to be about 54-55C to make the flue gasses condense.

The energy clawed back is about 12% to the best non-condensing boiler.

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Default High return temperature on condensing boiler CH

In article , Mark
writes
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.

It sounds as if your system has not been balanced, many (lazy)
installers say that this is not required on systems with TRVs which is
not true.

Follow the balancing procedure in the DIY faq at:
http://www.diyfaq.org.uk/plumbing/he...ngsystems.html
--
fred
BBC3, ITV2/3/4, channels going to the DOGs


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Default High return temperature on condensing boiler CH

On Wed, 29 Oct 2008 18:09:43 +0000, fred wrote:

In article , Mark
writes
Hi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?

What is a good solution for this? I don't think the pump is
adjustable.

It sounds as if your system has not been balanced, many (lazy)
installers say that this is not required on systems with TRVs which is
not true.

Follow the balancing procedure in the DIY faq at:
http://www.diyfaq.org.uk/plumbing/he...ngsystems.html


I did try to balance it, but had trouble getting good temperature
readings. I bought an IR thermometer for this purpose. I can get
stable temperature readings off everything but the ******* CH pipes.
If I pointed it at them the reading was all over the place.

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.
See http://improve-usenet.org

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Default High return temperature on condensing boiler CH

In article ,
Mark wrote:
I did try to balance it, but had trouble getting good temperature
readings. I bought an IR thermometer for this purpose. I can get
stable temperature readings off everything but the ******* CH pipes.
If I pointed it at them the reading was all over the place.


Put some black PVC tape round the pipe and measure on that.

--
*It was recently discovered that research causes cancer in rats*

Dave Plowman London SW
To e-mail, change noise into sound.
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Default High return temperature on condensing boiler CH

On 29 Oct, 18:09, fred wrote:
In article , Mark
writesHi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. *As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?


What is a good solution for this? *I don't think the pump is
adjustable.


It sounds as if your system has not been balanced, many (lazy)
installers say that this is not required on systems with TRVs which is
not true.

Follow the balancing procedure in the DIY faq at:http://www.diyfaq.org.uk/plumbing/he...ngsystems.html


The installers put a TRV on the return and a lock-shield on the flow
of one of my rads. Will this cause an issue where balancing is
concerned?

Thanks,

Jon
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Default High return temperature on condensing boiler CH

Jon wrote:
On 29 Oct, 18:09, fred wrote:
In article , Mark
writesHi,

My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?
What is a good solution for this? I don't think the pump is
adjustable.

It sounds as if your system has not been balanced, many (lazy)
installers say that this is not required on systems with TRVs which is
not true.

Follow the balancing procedure in the DIY faq at:http://www.diyfaq.org.uk/plumbing/he...ngsystems.html


The installers put a TRV on the return and a lock-shield on the flow
of one of my rads. Will this cause an issue where balancing is
concerned?


Not really. Some TRVs used to not like being on the return, but most are
bidirectional these days. Makes no difference to balancing though.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
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Default High return temperature on condensing boiler CH

On 31 Oct, 00:10, John Rumm wrote:
Jon wrote:
On 29 Oct, 18:09, fred wrote:
In article , Mark
writesHi,


My boiler shows the return temperature of the CH on its display.
Earlier today it was showing 75(C) which seems very hot. *As it is a
condensing boiler won't this mean it is operating outside its
condensing mode?
What is a good solution for this? *I don't think the pump is
adjustable.
It sounds as if your system has not been balanced, many (lazy)
installers say that this is not required on systems with TRVs which is
not true.


Follow the balancing procedure in the DIY faq at:http://www.diyfaq.org..uk/plumbing/h...ngsystems.html


The installers put a TRV on the return and a lock-shield on the flow
of one of my rads. Will this cause an issue where balancing is
concerned?


Not really. Some TRVs used to not like being on the return, but most are
bidirectional these days. Makes no difference to balancing though.

--
Cheers,

John.


Thanks John.
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