Zone Valve positioning

[sheff paul]

The installation of terrier valves in every radiator is a good idea specially in the bedrooms, but that will not provide boiler interlock. In that case radiators will be shut but boiler will carry on working for as long as the programmer is on through the by pass. The by pass should be installed before the motorised valves because that will open when motorised valves close for boiler overrun in order to cool down.

I for one would be using a room stat down stairs,and upstairs programmable TRV's,yes I know the boiler shuts off with the room stat,but most building inspectors wouldn't have a clue anyway,but I can guarantee the heat exchanger on the combi will last far longer,and will run quieter,dont mind multiple zones on unvented, system boiler installations,but on a standard combi installation its hard to be competitive,and up our way I know that over a 100 fits a week are going in on local authority houses all unzoned

 

[dancinplumba]

Sorry you know much more than me about the HVAC industry and hydraulics can't help you anymore, hell 10 post and a full blow plumber, what a Forum, why did I waste 55 years of my life

Bye

You even suggested he puts hw zone valve on....it's a combi
PS: bye bye

 

[prs999]

Hi,

The main reason I am going zoned is to save energy and money in the long run, we currently have a trv only setup in the house we are in at the moment and we still seem to be heating the whole of the upstairs as well as the downstairs for no reason. yes you can adjust the trvs to balance this out but this would mean daily adjustments, having 2 separate zones would automate this a lot better for not a huge extra installation cost, I know as an installer the cost of this will probably price you out of a lot of jobs but as an end user making this decision I am happy with the cost implications

Thanks

 

[prs999]

Thanks for all of your help, does the auto bypass have to be in the relms of a radiator or could I just tap a loop of 22mm pipe off before all of the zone valves and the return to allow for cool down? we will be installing a combi ans if I could loop some pipe through the back of a built in cupboard the mrs might give me less jip for removing the airing cupboard!

As promised Worcester Bosch's response to the above

[FONT=&quot]A bypass will be required. This could be a copper pipe as far from the boiler as possible, but it would be more effective if a radiator was kept off the zone system to dissipate the heat for obvious reasons. This is subject to customer comfort, of course. A towel rail is usually a good example. [/FONT]
[FONT=&quot]Regards,

I will ask Worcester but do you think this a towel rail would need a bypass relief valve on it as well if it was not to be used as a main source of heating?

Cheers
[/FONT]

 

[happyflyer]

You even suggested he puts hw zone valve on....it's a combi
PS: bye bye

I don't read in the lines, he would have fitted one anyway or he would have been back or here asking where it should go, then someone would tell him.

 

[dancinplumba]

I don't read in the lines, he would have fitted one anyway or he would have been back or here asking where it should go, then someone would tell him.

Thought you gone bye bye ? Always 'read in the lines' it's how one learns, or don't you need to ?

 

[Egidio]

In order to save money and have a good installation you can as you intend to anyway, the auto by-pass could be replaced for a towel rail in the bathroom as Prs999 suggested the only thing is that you have to run separate flow and return from before the motorised valves. Both zones can be controlled in temperature and time and both interlocking with the boiler.
Don't make the mistake of just fitting trv's everywhere because on that zone the thermostat will reach temperature and if that happens the boiler will carry on working even if all the radiators are closed.
trv's should be fitted specially in bedrooms and closed rooms, open areas where the thermostat is should be controlled trough the thermostat and ideally if the system is well designed and balanced, then all rooms in the same zone should heat up more or less at the same time.

 

[dancinplumba]

A towel rail is not a suitable bypass, it's not automatic and cust could close it. Worcestershyte bosch talking pap IMO

 

[kozak1968]

Sorry to butt in its 150 sq metres, so a standard semi would be just under (75 sqm downstairs and 75 sqm upstairs)

Hi there, the position does not realy matter. What you should consider is that you may not need zone valves, deppending on the size of the house. You should have the system split if the house is over 100 sqm. If you do have two zone valves then is good to have an auto by-pass to help cooling down the boiler when overruning, the auto by-pass should be at some distance from the boiler in order to allow the cooling down in that bit of pipework ( some two, three meter would be good).
All the modern boiler have overrun.

 

[Simon F]

you may not need zone valves, deppending on the size of the house. You should have the system split if the house is over 100 sqm.

Sorry to butt in its 150 sq metres, so a standard semi would be just under (75 sqm downstairs and 75 sqm upstairs)

Up to 150m2, 2 zones with separate thermostatic control but on the same time control.
Over 150m2, split zones with separate thermostats and separate time control for each zone.
(different for single storey)

http://www.planningportal.gov.uk/uploads/br/domestic_building_compliance_guide_2010.pdf

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