Can you get 15mm 2-port motorised valves?

I am considering overhauling and zoning my central heating later this year, and would like separate control of each rad. I'm looking for motorised valves which are as small as possible and which will fit on 15mm pipes. The only ones I can find are 22mm. [Yes, I know I can use reducers - but the whole thing is still too big].
Does anyone know whether smaller ones are available and, if so, where from?
TIA.
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

year,
The
I assume they will be visible.

from?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Set Square wrote:

I am planning to do something similar, linking it all into a home automation system. I was planning to use solenoid valves, as (like you) I have discounted motorised valves as too big / unwieldy.
I'll probably buy mine from Asco (www.ascojoucomatic.com) as that is who we use at work, but there are plenty of other suppliers, including RS (example part number 439-127)
The only concern I have is the 'clunk' as they switch, but hopefully an anti water hammer model will avoid that.
HTH,
Chris
--
cut along the dotted line to reply


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

year,
The
from?
I have seen ones in Scandanavia that appear to use the valve from a TRV together with what I assume is an electromagnet. This is 15mm and very small, though the peak flow is quite low I imagine.
But not sure where you get them in the UK.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The ones I've heard of use the mechanics of a TRV and a heater to activate the TRV capsule. Have seen them recently in individual hospital rooms to have timed control but they seem to be v expensive by virtue of low demand. They have been mentioned in this group, try a google groups. Andy Gabriel I think has mentioned making a low cost version by adding a heater to a regular TRV, again google.
--
fred

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

this
motorised
pipes.
but the

where
TRV
very
activate
to
Search for "prefect controls". I have posted about my experience with these heads for trv bases a couple of times, and I'm still pleased with the results. I have three of these waiting for a suitably shaped tuit.
--
Kevin Poole
**Use current month and year to reply (e.g. snipped-for-privacy@mainbeam.co.uk)***
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 23 Feb 2004 07:54:37 +0000, Autolycus wrote:

The obvious way would be to use a couple of reducing 22/15 sets in place of the 22mm olive in a 'standard' control.
--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In an earlier contribution to this discussion,

We seem to have gone full circle! In my original post - quoted in full above - I said, "Yes, I know I can use reducers - but the whole thing is still too big"!
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
honeywell have just produced a valve that replaces the rad valve and can be set up for various tempratures in each room which is cordless and will send a signal to the boiler to fire when a rad requires it. probably costs a fortune !

which
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

can be

send
a
If you are referring to the HR80, I phoned RKM Heating Controls for pricing, as suggested by Set Square, but they have not had any details from Honeywell yet. Also, the CM67z is a 2-zone affair and from a previous thread it seems Set Square wants more control than that.
Regards
Neil
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In an earlier contribution to this discussion,

Yes, that's right! It currently looking like a CM67 (not z) in each room, with one of those wax-heating valves on each rad. I'd still really prefer a motorised valve which could be fitted in the 15mm pipework under the floorboards or inside cupboards - and which is much smaller than a normal 22mm valve plus reducers - since far less would then be visible, and there wouldn't be any cables connected to the rads. Unfortunately, I haven't found anything suitable yet!
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

and
cordless
it.
details
room,
prefer a

normal
there
found
Gap in the market?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In an earlier contribution to this discussion,

Maybe! Or maybe the motor part would still have to be the same size - in which case there wouldn't be much saving in space by the valve itself being 15mm rather than 22mm.
Unless anyone knows differently . . .?
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

the
<Ahem!>
http://groups.google.com/groups?selm=Pine.WNT.4.21.9912071852570.232-100000%40supc16.rdg.ac.uk
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ah, the original and best. Good thread, sorry I missed it; I was a bit busy in '99 ;-). I've eight zone valves in my control cupboard, with sep pipes to each zone (room). Pipe runs were easy for me so I went that route. Retrofit or difficult runs & I'd be going the resistor route, needs the right TRV tho'; the cheapies I got from s'fix would have been a b'ger to modify, Draytons strike me as an easy option with the big exposed head <??>.
--
fred

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Set Square wrote on Sunday (22/02/2004) :

Solenoid valve are available which are quite small, the problem might be the noise they make as they energise and de-energise. They are though much more reliable than motorised valves.
--

Regards,
Harry (M1BYT) (L)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

A good solution for this is to use Sauter drives in place of the TRVs.
The cheapest is the AXT111 F200 which is a thermal drive. These fit onto the base of a TRV in place of the normal head
http://www.sauter-controls.com/pds/pds/pdf/pd55012e.pdf
The valve is held closed with a spring to turn it off. When heat is required, power (230v, although there is a lower voltage one) is applied. This warms an expansion element and opens the valve. Operation is silent and in operation they use under 3W.
RS have these at about 35, but a better deal should be possible from Controls Center.
You could also fit one of these drives onto a 15mm base which Sauter also makes.
I've used some of Sauter's motorised drives (AXM 117S)
http://www.sauter-controls.com/pds/pds/pdf/pd55011e.pdf
These run with a 24v supply and can be set to any position with a 0-10vDC control voltage. They are also silent in operation, but cost more than the thermal ones. I'm designing a special purpose system which provides the necessary control voltages.
It should be possible to control a thermal drive with either a simple thermostat or a pulse proportional controller like a CM67 or equivalent.
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In an earlier contribution to this discussion,

Sounds interesting, and could be better than trying to hide motorised valves under floorboards etc. I note from the pdf file that they also have optional auxiliary contacts - which should make it possible to integrate them into an S-Plan-plus control system. The only thing is, though, that the contacts make when the valve is 35%-50% open rather than fully open. I'm not sure whether this is a problem? I suppose if the boiler and pump fire up a bit early, it's not too disastrous as long as there is an automatic by-pass circuit. I suppose, also, that it's far better than the alternative of having a relay in parallel with the valve - which switches when the "start to think about opening" command is sent to the valve!
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I don't think that that would be a problem at all.
Think about the behaviour of simple TRVs. These have a thermal capsule which expands and pushes down the pin of the valve. This is an "analogue" effect, not a "digital" one, so at different room temperatures the valve would be anywhere from fully open to fully closed.
If you are concerned about the bypass aspect, you could always fit a pressure activated automatic bypass valve.
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.