Safety zone valve to cylinder

[feebs73]

Help
Is there anybody out there that can point me in the write direction for a wiring diagram for a cylinder safety zone valve, i am stuggling to find any diagrams on this, i find it hard to belive that this saftey valve system is hard to find as this is apparently very important to stop a pressurised cylinder blowing.
feebs 73

 

[Megavolt]

Help
Is there anybody out there that can point me in the write direction for a wiring diagram for a cylinder safety zone valve, i am stuggling to find any diagrams on this, i find it hard to belive that this saftey valve system is hard to find as this is apparently very important to stop a pressurised cylinder blowing.
feebs 73

What unvented cylinder is it. You basically need to interrupt the zone valve supply via the cylinders high limit stat

 

[feebs73]

Hi Elrick
I dont know of the top of my head about the cylinder, i think it is a builder center's own brand it is about 5ft tall with a single immersion element, do you have a wiring diagram on how it is incorporated in the 1-10 choc block.
Many thanks
Feebs73

 

[Megavolt]

Best I can do read around page 11. Put will change depending on make and model

http://www.plumbcenter.co.uk/wcssto...all/ti/on/Center_Centerstore_Installation.pdf

 

[feebs73]

Thanks again
Just had a look at that link, I can see the basic wiring diagram but not one incorporating that 3rd valve.
Thanks once again
Feebs 73

 

[JD Hogg]

You don't need 3 zone valves. You just need to wire the hot water tank zone valve supply in series with the tank stat. You only need a safety zone valve if you are using a Y plan system (i.e a mid position valve or three port valve), in this case the 2 port zone valve is connected in the primary flow to the hot water cylinder and again the zone valve supply is wired via the tank stat.

 

[feebs73]

Ok thanks for that jd hogg,

 

[Megavolt]

You don't need 3 zone valves. You just need to wire the hot water tank zone valve supply in series with the tank stat. You only need a safety zone valve if you are using a Y plan system (i.e a mid position valve or three port valve), in this case the 2 port zone valve is connected in the primary flow to the hot water cylinder and again the zone valve supply is wired via the tank stat.

Tank stat or high limit stat two completely different things

 

[JD Hogg]

It's simple really, the unvented cylinders come as a package with everything you need so if you use all the bits and everything is installed correctly all should be well. For the majority of packages you would get one thermostat called a dual stat which is in fact a combined high limit stat and tank stat (control stat). You would only use a seperate high limit stat if you were installing a dual fuel cylinder e.g. solar or a Y plan system.

 

[Amp David]

Ok thanks for that jd hogg,

Sure this was answered in the in the other post, but never mind.

Who ever has done the plumbing must of made sure that the 2 port valve for the hot water is positioned between the cylinder and blow off/expansion pipe that goes into the tank in loft.





(description of said pipe may be wrong lol).

 

[JD Hogg]

Sure this was answered in the in the other post, but never mind.

Who ever has done the plumbing must of made sure that the 2 port valve for the hot water is positioned between the cylinder and blow off/expansion pipe that goes into the tank in loft.





(description of said pipe may be wrong lol).

Unvented cylinders don't have such a pipe

 

[Amp David]

Thought we were on about vented sorry, go mixed up with his other thread

 

[chris murphy]

Help
Is there anybody out there that can point me in the write direction for a wiring diagram for a cylinder safety zone valve, i am stuggling to find any diagrams on this, i find it hard to belive that this saftey valve system is hard to find as this is apparently very important to stop a pressurised cylinder blowing.
feebs 73

"Hello feebs 73",


I have posted another message in answer to You about this on the original thread here:

http://www.electriciansforums.net/c...ntral-heating-3-zone-valves-2.html#post637425

Some of the Members on this thread have got the correct idea about the `Thermal Cut Out` / High Limit Thermostat being wired to interupt the power to the TWO Port Zone Valve and therefore Close it in the event of the High Limit Thermostat having to operate.

Please also read My reply to Amp David below and then please go to My reply to You on the original Topic [Link above].


I have gone into quite a lot of detail in My latest message to You on that thread - but what I have posted needs adding to in order to accommodate the requirements of the Unvented Hot Water Cylinder and the Heating Zones - plus the Underfloor Heating Controls.

THAT is definitely beyond My capabilities to `design` and explain to You - one of the Electrical Expert Members should be able to adapt the Diagram that I have posted to an `S Plan PLUS` and add the additional wiring for the Underfloor Heating Controls.



Regards,


Chris - Heating Engineer

 

[chris murphy]

Sure this was answered in the in the other post, but never mind.

Who ever has done the plumbing must of made sure that the 2 port valve for the hot water is positioned between the cylinder and blow off/expansion pipe that goes into the tank in loft.





(description of said pipe may be wrong lol).

"Hello Amp David",


The Unvented Cylinder Zone Valve must be a Two Port Valve - `Spring Return closing` [Usually supplied by the Unvented Cylinder Manufacturer] - and is installed on the Flow to the Unvented Hot Water Cylinder.

As well as being wired in an `S Plan` for the Heating and Hot Water System Controls there MUST be wiring from the Unvented Cylinder`s Thermal Cut Out / High Limit Thermostat which interrupts the power to the Zone Valve in the event that the Thermostat operates - thus allowing the Zone Valve to return to the Closed position [Spring Return].

This stops the Heat from circulating around the Cylinder Coil and further increasing the Temperature of the Domestic Hot Water and the possible over-pressurisation of the Unvented Cylinder - IF the Temperature and Pressure Relief Valve malfunctioned and did NOT discharge the over pressure.

If You want to read My VERY long message to feebs 73 about this I have posted a Link to the original Topic in My reply to Him above.

I have attached a Diagram of an EXAMPLE of the wiring for a Heatrae Sadia Megaflow Unvented Indirect Hot Water Cylinder in case anyone else is interested in this.

Obviously people should refer to the EXACT wiring Diagram for the Unvented Hot Water Cylinder that they are wiring and NOT take it for granted that this would be correct for ALL Unvented Cylinders.


Regards,

Chris - Heating Engineer

 

[Amp David]

CHeers Chris,


It was my mistake, thought he was originally on about a vented system.

Totally see what you mean in the above post though

 

[chris murphy]

Hi Elrick
I dont know of the top of my head about the cylinder, i think it is a builder center's own brand it is about 5ft tall with a single immersion element, do you have a wiring diagram on how it is incorporated in the 1-10 choc block.
Many thanks
Feebs73

"Hello again feebs 73",

JUST to make sure that You are asking about an `INDIRECT` Unvented Hot Water Cylinder - regarding your description above [which I have just noticed] - have I been correct in My assumption that there IS a Flow and Return from the Heating System connected to the Unvented Cylinder to Heat the Hot Water via the Cylinder Coil ?

I have been answering You on that assumption because it would be impossible to Heat an Unvented or a Vented Cylinder to meet the needs of a property with `3 Ensuite Bathrooms / Shower Rooms` using an Immersion Heater - unless the Bathing / Showering was being done at different times for each Bathroom.

Even with the Flow and Return from the Boiler it might not be capable of `recovering` the Hot Water temperature quick enough for perhaps 3 consecutive Showers [?] - But that is not your problem.

I assume that You just mean that it ALSO has an Immersion Heater fitted - But will primarily be Heated by the Boiler / Heating Flow and Returns ?

IF NOT - then I have written a LOT of `Non Applicable` Information in My replies to You !


Regards,


Chris

 

[feebs73]

Hi chris
the 5 bedroom 3 ensuite job was a different one to the origanal posting regarding the 3rd zone valve( safety valve), I was just asking about the 5 bed job because in my eyes it is the same s plan just on a bigger version than the origanal post, but does not have the safety valve that has been mentioned before.
many thanks feebs73

 

[chris murphy]

Hi chris
the 5 bedroom 3 ensuite job was a different one to the origanal posting regarding the 3rd zone valve( safety valve), I was just asking about the 5 bed job because in my eyes it is the same s plan just on a bigger version than the origanal post, but does not have the safety valve that has been mentioned before.
many thanks feebs73

"Hello again feebs 73",


Sorry that I misunderstood Your Post on this thread - I thought that You were just trying to get the information by rewording the question.

I am a bit confused by the title of THIS thread - `Re: Safety zone valve to cylinder` - what are You asking about HERE ?


Also did You read My VERY Long message to You on the `other` thread about the `Safety / Thermal Cut Out`wiring / and example Wiring Diagram for the Unvented Cylinder`s Zone Valve ?


Regards,

Chris

 

[chris murphy]

You don't need 3 zone valves. You just need to wire the hot water tank zone valve supply in series with the tank stat. You only need a safety zone valve if you are using a Y plan system (i.e a mid position valve or three port valve), in this case the 2 port zone valve is connected in the primary flow to the hot water cylinder and again the zone valve supply is wired via the tank stat.

"Hello JD Hogg",

On an Unvented Indirect Hot Water Cylinder the Two Port Zone Valve operation MUST also be wired to the Thermal Overheat Thermostat / `High Limit Thermostat` fitted to the Unvented Cylinder - If this ever operates it interupts the power to the Zone Valve which then closes via the spring return.

This obviously stops the Heat circulation to the Unvented Cylinder Coil and prevents further Overheating and possible Over-pressurisation of the Unvented Cylinder in the event that the Pressure and Temperature Relief Valve malfunctioned and did NOT release the Over-pressurisation - which although unlikely is possible.

Regards,

Chris - Heating Engineer

 

[chris murphy]

Hi chris
the 5 bedroom 3 ensuite job was a different one to the origanal posting regarding the 3rd zone valve( safety valve), I was just asking about the 5 bed job because in my eyes it is the same s plan just on a bigger version than the origanal post, but does not have the safety valve that has been mentioned before.
many thanks feebs73

"Hello again feebs 73",


Have You seen My latest messages to You on the other thread ?

Also - having read your comment above - is the Underfloor Heating in the same property as the Unvented Hot Water Cylinder / `3 Zones Valves` thread that We have been corresponding about ?

If not - I feel that You confused matters when You mentioned the description about the `5 Bedroom - 3 Ensuites - Underfloor Heating to the Ground Floor` etc. during the correspondence about the Unvented Hot Water Cylinder / `3 Zone Valves` thread - although obviously unwittingly - I thought You were describing the Job that We were writing about ?

Until NOW [having read your comment above] I have thought that this was the SAME Job / Heating System / Wiring enquiry - ?


What I have written on the ORIGINAL thread about the S Plan Plus and the Thermal Protection / `High Limit Thermostat of the Unvented Hot Water Cylinder would still be fully applicable - BUT - I have been involved in a slight `debate` with another Member about the `Ground Floor Underfloor Heating` being wired seperately to the S Plan Plus wiring plan.

IF it is NOT installed in the property that we first started corresponding about I would NOT have kept mentioning it and trying to elicit responses including the wiring for that on Your behalf from the other Members.

Could You please clarify this point - "Thanks".


Regards,

Chris