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Default TRV stuck

Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.
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Default TRV stuck

On 22 Nov, 13:50, Fred wrote:
Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?


Pull it out. Then check it's working by pushing it in and releasing it
a few times. The total movement is only a few millimetres.

Would a little 3-in-1 or WD40 on it prevent this happening again?


Lubricant might help, but usually they are stuck internally due to
crud inside.

A good tip is to open all the TRVs full when the heating goes off for
the summer. The only problem is that other people go around closing
them thinking "We don't need the radiators on in this weather." This,
of course, is the converse of the present problem where they whack
them up full because "The radiator's gone cold."

I do wonder how much "carbon" could be saved by an advertising
campaign to tell people how to use TRVs properly.

Chris
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Default TRV stuck

Fred wrote:
Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?


The pin is pushed to shut off the water flow. So if it is stuck down
then it is off.

Pulling it may free it, or you may find it is a free floating pin not
actually attached to the valve mechanism in which case pulling it will
make no difference.

A few gentle taps with a small hammer on the side of the valve may free it.

Would a little 3-in-1 or WD40 on it prevent this happening again?


Probably not...

--
Cheers,

John.

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Default TRV stuck


wrote in message
...

I do wonder how much "carbon" could be saved by an advertising
campaign to tell people how to use TRVs properly.

Or getting rid of the wretched things completely and using
sensibly-positioned thermostats and motorised valves of a size and
design that you wouldn't mind having them visible. I have used Sauter
AXT111 actuators, but they're so far off being a mainstream product that
they're too expensive for many purposes - and difficult to find with
auxiliary switches.

Guess who's in the process of designing a heating system and wants it
fully zoned - 5 rooms - and adjustable to real, understood, temperature
values, and set without grovelling on the floor, trying to move a valve
between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.


--
Kevin Poole
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Default TRV stuck

A few gentle taps with a small hammer on the side of the valve may free
it.


I find that often if you tap it inwards firmly with a small hammer it
displaces the crud, then springs out on the spring.




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Default TRV stuck

In article , Autolycus
writes

wrote in message
...

I do wonder how much "carbon" could be saved by an advertising
campaign to tell people how to use TRVs properly.

Or getting rid of the wretched things completely and using
sensibly-positioned thermostats and motorised valves of a size and
design that you wouldn't mind having them visible. I have used Sauter
AXT111 actuators, but they're so far off being a mainstream product that
they're too expensive for many purposes - and difficult to find with
auxiliary switches.

Guess who's in the process of designing a heating system and wants it
fully zoned - 5 rooms - and adjustable to real, understood, temperature
values, and set without grovelling on the floor, trying to move a valve
between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.

You could do worse than to look at the multizone RF system offered by
Honeywell, sorry I don't have the numbers but it should be easy to find.
IIRC, set points are sent to RF radiator valves and the control is done
locally. I have no time for the RF fad but think that the only way that
multizone control will reach the mass market is that way as both new
build and retrofit would find multizone cabling too costly. The
Honeywell system claims proportional control and the intelligence to
shut down heat in a room that has a window open for ventilation if
desired.

My own system has a zone valve for each room but controls for such a
system have to be home grown and proportional control using off the
shelf components is just not an option.
--
fred
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In article fred wrote:

You could do worse than to look at the multizone RF system offered by
Honeywell, sorry I don't have the numbers but it should be easy to find.
IIRC, set points are sent to RF radiator valves and the control is done
locally.


http://www.cm-zone.com/application.php?language=en costs about
500 quid for a kit to control 6 existing TRVs. but only provides 2 zones. If
you wanted totally independent zones for each room you could add up to 3
extra CM67z controllers at about 80 quid each, providing 2 more zones per
controller.

--
Mike Clarke
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Default TRV stuck

On 2007-11-22 13:17:09 +0000, Huge said:

On 2007-11-22, Fred wrote:
Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?


Pull.

Don't pull *too* hard - I've known them come out completely, followed by a
little fountain of evil black water. And on Christmas Day, too....


That's what happens when you say you don't believe in God :-)




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In article , Lobster
writes
wrote:

I do wonder how much "carbon" could be saved by an advertising
campaign to tell people how to use TRVs properly.


Damned right.

How many people (like SWMBO, to name but one) come into a cold house,
switch the heating on and crank up all the TRVs to max, rather than
leaving them set at 2-3 where they were previously set for a comfortable
operating temperature, because that way "they'll warm up quicker".

And then later - "bloody hell it's hot in here, I'll open the windows"

Bless her.

Indeed, I have given up explaining the concept of thermostats and why
raising the setting does not result in an increase in comfort level, I
spend my time either slapping heads or installing tamperproof controls
:-/
--
fred
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In article , Mike Clarke
writes
In article fred wrote:

You could do worse than to look at the multizone RF system offered by
Honeywell, sorry I don't have the numbers but it should be easy to find.
IIRC, set points are sent to RF radiator valves and the control is done
locally.


http://www.cm-zone.com/application.php?language=en costs about
500 quid for a kit to control 6 existing TRVs. but only provides 2 zones. If
you wanted totally independent zones for each room you could add up to 3
extra CM67z controllers at about 80 quid each, providing 2 more zones per
controller.

That's probably the one but I refuse to navigate such an appalling site
to confirm it. I think there is a route to expand it beyond the basic 2
zones.
--
fred
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"Mike Clarke" wrote in message
...
In article fred wrote:

You could do worse than to look at the multizone RF system offered by
Honeywell, sorry I don't have the numbers but it should be easy to
find.
IIRC, set points are sent to RF radiator valves and the control is
done
locally.


http://www.cm-zone.com/application.php?language=en costs about
500 quid for a kit to control 6 existing TRVs. but only provides 2
zones. If
you wanted totally independent zones for each room you could add up to
3
extra CM67z controllers at about 80 quid each, providing 2 more zones
per
controller.

Hmmmm. And you're still sensing room temperatures at the bottom corners
of radiators, unless, aiui, you have one CM67z per room.

So, for my system, I'd need:

an HC60NG receiver - £64
five HR80UK valve heads @ £67 - £335
five CM67 @ £60 - £300 (or would that have to be 4 plus
1 other of some sort?)
five trv bodies - say - £ 50

i.e. about £750.

Or
Five programmable room stats @ £32 £160
Five motorised valves @ £22 £110
Five lockshields £ 10
a wiring centre £ 10
cable and fittings

i.e. about £325

Less sophisticated control, and it's more work wiring it all up, but
each item can be replaced if it fails by something functionally
identical from another maker, and it leaves £425 to spend on tools, or
sweets.

If Tower can make a 22mm motorised valve and bes can sell it for £22,
surely it shouldn't be beyond the wit of man incorporate one in a
radiator valve for about the same price?


--
Kevin Poole
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In article Autolycus wrote:

[snip - comparison of Honeywell CM Zone Wireless system against hardwired
motorised valves]

Less sophisticated control, and it's more work wiring it all up, but
each item can be replaced if it fails by something functionally
identical from another maker, and it leaves £425 to spend on tools, or
sweets.


I'm inclined to agree there. I looked at the CM Zone option as a less
disruptive way of applying zones to our existing system but dismissed it as
an expensive approach with some practical drawbacks. If we were starting
from scratch I'd go for zones with motorised valves but I don't fancy the
disruption so I expect we'll settle for a relatively cheap and cheerful
addition of a CM927 to the existing system which has TRVs throughout but no
room stat.

--
Mike Clarke
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Default TRV stuck

In article ,
"Autolycus" writes:
Or getting rid of the wretched things completely and using
sensibly-positioned thermostats and motorised valves of a size and
design that you wouldn't mind having them visible. I have used Sauter
AXT111 actuators, but they're so far off being a mainstream product that
they're too expensive for many purposes - and difficult to find with
auxiliary switches.

Guess who's in the process of designing a heating system and wants it
fully zoned - 5 rooms - and adjustable to real, understood, temperature
values, and set without grovelling on the floor, trying to move a valve
between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.


I suspect that maybe OTT.

I designed and installed central heating about 6 years ago.
I split into downstairs and upstairs zones with separate control.
I did accurate heatloss calculations for each room and sized the
rads appropriately. TRVs are fitted on all rads except in the two
rooms with thermostats, but I simply leave them fully open all
the time. With the radiators matching the heat loss from each
room, all rooms match each other temperature-wise, and when the
rooms with the stats are at the right temperature, so are all
the other rooms.

If I hadn't done accurate heat-loss calculations, then TRV's
would have been necessary to get desired temperatures, but with
proper heat-loss calcs and accurately sized rads, they aren't
doing anything. If I'd known how accurate my heat-loss calcs were,
I might not have bothered fitting the TRVs at the time. (However,
they or something equivalent are needed by Part L nowadays.)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
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In article ,
Huge writes:
On 2007-11-22, fred wrote:
In article , Lobster
How many people (like SWMBO, to name but one) come into a cold house,
switch the heating on and crank up all the TRVs to max, rather than
leaving them set at 2-3 where they were previously set for a comfortable
operating temperature, because that way "they'll warm up quicker".

And then later - "bloody hell it's hot in here, I'll open the windows"

Bless her.


Indeed, I have given up explaining the concept of thermostats and why
raising the setting does not result in an increase in comfort level, I
spend my time either slapping heads or installing tamperproof controls


I'm glad to see that it's not just my wife who does this.

I might as well replace the heating thermostat with one of those great big knife
switches out of a Frankenstein movie, because that's how she treats it.


I have what looks like regular Satchwell thermostats on the wall
(DRT-3451's for anyone interested), but inside they are just a
potentiometer, the setting of which is read by the computer which
controls my heating. The computer can be set to read them or to
use some specified setting and ignore them, so I can effectively
override the wall stat setting. That might be a way to resolve
this;-)

Alternatively, buy another wall stat and stick it to the wall
with double-sided sticky pads without connecting it to anything,
and tell the rest of the family that's the new thermostat:-)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
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Default TRV stuck

Autolycus coughed up some electrons that declared:

five CM67 @ £60 - £300 (or would that have to be 4 plus
1 other of some sort?)


http://www.heizungsprofi24.de/hauste...rtzugriff.html

Is the "1 other" that may be of interest. Not available[1] in the UK due to
Honeywell UK thinking that we're all too stupid to read the manual for such
a beast.

[1] But is available as part of a full installation service for lots of
wonga plus silly markup on the components.

Also available from www.smuk.at

HTH

Tim

PS Not tried it but read the specs, it looks pretty good.
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ARWadsworth coughed up some electrons that declared:

Tell me about it. I used to be married to someone who was brought up in a
communist country where there were no such things as gas meters and bills
in the "very attractive" high rise flats she lived in. Heating on full
24/7 and using the window as a thermostat.


I have holidayed in a couple of such flats in Riga and Vilnius. Big central
boilers on each estate and, as you say, unlimited heating. There was talk
in Riga of putting usage metering on the rads and hot water though.

Same system in China, but sometimes you don't get the how water, just the
central heating.

Cheers

Tim


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Fred coughed up some electrons that declared:

Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.


Just dealt with two such stuck valves. Take the head off (the dry bit only),
then see if you and push the pin in (not too hard mind).

If not, try a sharp tap with a light metal tool, eg pliers or pin hammer.
You are looking to invoke a small shock to crack the stuck valve open, not
to hit it so hard you damage it, or upset the compression/screw fittings.

Worked on both of mine. Then put the head back and turn on and off a few
time, which should finish the job.

If that doesn't work, don't get any more violent or you might get wet, in a
black yukky magnetity sort of way. Buy a new valve and fit when convenient.

Cheers

Tim
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On 24 Nov 2007 13:55:35 GMT Andrew Gabriel wrote :
I designed and installed central heating about 6 years ago.
I split into downstairs and upstairs zones with separate control.


My flat is long and narrow, bed one end, kit/liv the other and
split 2 zones, 2 x CM67. Two rads in the hall one on each zone,
bathroom radiator is the bypass. Works brilliantly and is
economical too.

Sadly though I can't help think that many so-called pros would have
walked or quoted a mega price if asked to do something like this.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk

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Andrew Gabriel wrote:

Alternatively, buy another wall stat and stick it to the wall
with double-sided sticky pads without connecting it to anything,
and tell the rest of the family that's the new thermostat:-)


This could actually be an answer for the "I think a thermostat is just
an on off switch" brigade... sneaky ;-)

--
Cheers,

John.

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In message , Tim Southerwood
writes
Fred coughed up some electrons that declared:

Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.


Just dealt with two such stuck valves. Take the head off (the dry bit only),
then see if you and push the pin in (not too hard mind).

If not, try a sharp tap with a light metal tool, eg pliers or pin hammer.
You are looking to invoke a small shock to crack the stuck valve open, not
to hit it so hard you damage it, or upset the compression/screw fittings.

NO

Place a flat object (spanner head or something) on the pin and hit that

That way, you don't damage the pin

--
geoff


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Default TRV stuck

Fred wrote:
Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?



FYI I had a lockshield valve that was stuck t'other day whilst changing a
rad. Mole grips around the valve body, big adjustable on the flats of the
valve - and the bugger snapped clean off at the base of the flat.

New lockshield only £2:80, system drained so no real problem, but it could
have been.



--
Dave - The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257


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"Andrew Gabriel" wrote in message
...
In article ,
"Autolycus" writes:

snip
Guess who's in the process of designing a heating system and wants it
fully zoned - 5 rooms - and adjustable to real, understood,
temperature
values, and set without grovelling on the floor, trying to move a
valve
between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.


I suspect that maybe OTT.

I designed and installed central heating about 6 years ago.
I split into downstairs and upstairs zones with separate control.
I did accurate heatloss calculations for each room and sized the
rads appropriately.


snip

The additional constraints that have made me consider this fully-zoned
system a

1) It's a bungalow: the dining room has a small kitchen directly off
it, and has a large, south-facing window, but the lounge is north-facing
with a small window on the west wall, and has previously been found to
work well with two radiators. One bedroom faces north, one south.

2) It will be occupied by an elderly couple, who may wish to use the
rooms fairly flexibly (study-bedroom, etc) and who will almost certainly
want to be able to vary the temperature in odd rooms at odd times. I
think that only the bathroom is really amenable to a normal programmable
room stat, though they could be used in the other rooms.

3) They don't really want to be crawling round faffing with trvs,
especially since most are so coarsely calibrated that you can't easily
return them to a "standard" position. Remote heads for trvs seem to
have gone out of fashion. A dial, or a display, that they can set to
21, or 18 (or even better, 70 or 65) will be much more likely to be
used.

Thanks to Tim for the link, and to Thomas who emailed me

http://www.conrad.de/goto.php?artikel=560618

as a source of radio-controlled actuators. I wonder how long the
batteries last in the actuators? These would be an interesting
alternative to trvs in a system controlled overall by one roomstat, but
I can't at the moment see how to use a number of them to links as OR
inputs to call for heat from the boiler.

http://www.conrad.de/goto.php?artikel=611275 seems to be a similar
device to the Sauter AXT111, but isn't available with an auxiliary
switch.

In the system I envisage, when the room stat calls for heat, two things
will happen: the relevant valve(s) will open; and the boiler will get a
call for heat. This can be achieved using normally open actuators, and
an SPDT room stat, or by NC actuators and a bank of relays, or, easiest,
perhaps, by using conventional two-port motorised valves with auxiliary
switches. The latter have the further advantage that the boiler won't
be woken up till the valves are open, whereas with thermal actuators the
boiler will fire before there's anywhere for the hot water to go.

Boiler choice can be another thread ;-)

--
Kevin Poole
**Use current month and year to reply (e.g. )***

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In article , Autolycus
writes

The additional constraints that have made me consider this fully-zoned
system a

1) It's a bungalow: the dining room has a small kitchen directly off
it, and has a large, south-facing window, but the lounge is north-facing
with a small window on the west wall, and has previously been found to
work well with two radiators. One bedroom faces north, one south.

2) It will be occupied by an elderly couple, who may wish to use the
rooms fairly flexibly (study-bedroom, etc) and who will almost certainly
want to be able to vary the temperature in odd rooms at odd times. I
think that only the bathroom is really amenable to a normal programmable
room stat, though they could be used in the other rooms.

3) They don't really want to be crawling round faffing with trvs,
especially since most are so coarsely calibrated that you can't easily
return them to a "standard" position. Remote heads for trvs seem to
have gone out of fashion. A dial, or a display, that they can set to
21, or 18 (or even better, 70 or 65) will be much more likely to be
used.


In the system I envisage, when the room stat calls for heat, two things
will happen: the relevant valve(s) will open; and the boiler will get a
call for heat. This can be achieved using normally open actuators, and
an SPDT room stat, or by NC actuators and a bank of relays, or, easiest,
perhaps, by using conventional two-port motorised valves with auxiliary
switches. The latter have the further advantage that the boiler won't
be woken up till the valves are open, whereas with thermal actuators the
boiler will fire before there's anywhere for the hot water to go.

With full multi-zoning like this using simplified controls that don't
have synchronised demand you can find the boiler firing just to service
a call to heat for a one small room, leading to frequent boiler cycling.
When I designed my own system I plumbed it so that heat from the large
H/W cylinder could be stolen to meet light C/H demands, as with a
thermal store. The boiler would then only fire to top up the thermal
store (when operating on light loads). The extra components are a second
pump and a non-return flap valve to stop back flow through the boiler
and of course extra control to detect light loading. This phase of the
project has yet to be implemented as I have the 7 zones configured in 2
control banks (4+3) and the need for such fine control hasn't been
required. The control for the light loading would be simple logic but
proprietary.

An alternative is not to fire the boiler until either 2 or more rooms
call for heat or 1 room plus a fixed delay had timed out. The effect of
this is to try and force the zones into some sort of synchronised demand
but again this requires proprietary control.
--
fred
Plusnet - I hope you like vanilla
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geoff coughed up some electrons that declared:

In message , Tim Southerwood
writes
Fred coughed up some electrons that declared:

Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.


Just dealt with two such stuck valves. Take the head off (the dry bit
only), then see if you and push the pin in (not too hard mind).

If not, try a sharp tap with a light metal tool, eg pliers or pin hammer.
You are looking to invoke a small shock to crack the stuck valve open, not
to hit it so hard you damage it, or upset the compression/screw fittings.

NO

Place a flat object (spanner head or something) on the pin and hit that

That way, you don't damage the pin


I should been clearer: tap the side of the body of the valve, not the pin.
2 or 3 sharp light taps are often all it takes.

Yeah, hitting the pin with a hammer will bugger it up.


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In message , Tim Southerwood
writes
geoff coughed up some electrons that declared:

In message , Tim Southerwood
writes
Fred coughed up some electrons that declared:

Hi,

I've got a radiator that is not warming up and I think the TRV is
stuck. I know this happens now and again. If you take the top off,
there is a pin. I can't remember, do I push it in or pull it out to
release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.

Just dealt with two such stuck valves. Take the head off (the dry bit
only), then see if you and push the pin in (not too hard mind).

If not, try a sharp tap with a light metal tool, eg pliers or pin hammer.
You are looking to invoke a small shock to crack the stuck valve open, not
to hit it so hard you damage it, or upset the compression/screw fittings.

NO

Place a flat object (spanner head or something) on the pin and hit that

That way, you don't damage the pin


I should been clearer: tap the side of the body of the valve, not the pin.
2 or 3 sharp light taps are often all it takes.

Yeah, hitting the pin with a hammer will bugger it up.

Well, if you do as I typed above, it works

hitting the side of the body of the valve won't necessarily free the pin
off

--
geoff


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Default TRV stuck


"fred" wrote in message ...
snip my zoning ideas

With full multi-zoning like this using simplified controls that don't
have synchronised demand you can find the boiler firing just to
service a call to heat for a one small room, leading to frequent
boiler cycling. When I designed my own system I plumbed it so that
heat from the large H/W cylinder could be stolen to meet light C/H
demands, as with a thermal store. The boiler would then only fire to
top up the thermal store (when operating on light loads).


I like the concept, but I'd decided to do away with a cylinder
completely since there's only no bath and only one shower, and the
present cylinder is a Fortic.

I see that some (all?) modern combis claim to have short-cycling
prevention systems. Vaillant make a thing of it in their blurb, but
looking at the various state codes, it seems that Ultracom and Flexicom
Glow Worms have it too. I must investigate which others have it - I've
not decided on the boiler yet.

What they don't explain is how exactly it works: presumably, if there's
too little heating load for even the lowest burner modulation setting,
the boiler stops firing but the pump continues running. If the call for
heat ceases, then the pump over-run kicks in for its preset period, but
otherwise the boiler will not fire up until the defined "anti-cycling
period" has elapsed. It's unfortunate that although both Glow worm and
Vaillant allow the installer to set these periods within wide limits
(2 - 60 minutes), neither give any advice on why one should deviate from
the factory defaults. Glow worm do, however, insist on both a minimum
flow through the radiator the user can't turn off (or presumably the
smallest one in a fully-zoned system), defined in terms of temperature
rise through the boiler, _and_ a minimum total flow, including that
which goes through the bypass. Since there's no way of measuring this
directly, I can only think that you have to work this out from the pump
and bypass characteristics.

All this talk of short cycling and part loads makes me think that more
emphasis should be placed on the minimum output a boiler can be
modulated to, which varies widely from type to type. A Flexicom 30cx
goes down to 9.3kW, an Ecotec 831 goes to 8.7, but an Ultracom 30cx goes
to 4.95.

And this is without considering any of the newer "intelligent" stats
that communicate their every need to the boiler some mysterious way.
My brain hurts.


--
Kevin Poole
**Use current month and year to reply (e.g. )***

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On Sun, 25 Nov 2007 08:45:12 -0000, "Autolycus" wrote:

I wonder how long the
batteries last in the actuators? These would be an interesting
alternative to trvs in a system controlled overall by one roomstat, but
I can't at the moment see how to use a number of them to links as OR
inputs to call for heat from the boiler.


Wot they say, deep in the spec sheet: two years in the actuator, one year in the
wall stat -- pair of AA batteries in each.

http://www.conrad.de/goto.php?artikel=617501

has two room stats, controlled and programmed with a further controller, which
can also switch power and control dimmers by radio...

And the cotrollers do degrees Fahrenheit:-)



Thomas Prufer
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