Unvented Cylinders Ticket

[Foodface]

Had a customer call today saying they had a Worcester Bosch engineer out for what they thought was a boiler problem, turned out the motorised valve on their unvented cylinder had gone. They asked me to do it and I said no, as I hadn't done the ticket. Don't really come across them much and we predominately do servicing work, is it even worth doing the ticket?

Just wondered what people thought like.

Nice one

Fodface

 

[mountainman]

I'm not entirely sure that you need G3 to change a motorised valve as its not part of the 'unvented' side of the system.
As long as the new valve was spring return, normally closed the same as the old one.
It probably only needs a new motor or head and it would be a bit drastic to need the G3 ticket to change either of these.

 

[Foodface]

I spoke to my training providers and they said I needed the ticket to work on it, thought it best not to meddle if I was unsure. Not got a great deal of work in so will be a bit annoyed if I did the wrong thing.

 

[Millsy 82]

You dont need a ticket to swap a 2 port valve that would be like saying you have to be gas safe to change a pump. You cant touch the cylinder expansion vessel or the bits on the cold main going to it like pressure reducing valve pressure relief etc etc.

 

[lame plumber]

two port on the coil is a safety device as well on an unvented and part of the system so the rules would say you need an unvented ticket.

 

[Howsie]

I agree with Lame as wrong as it sounds. On both counts

 

[lame plumber]

I agree with Lame as wrong as it sounds. On both counts

get back in your box, just like to tell it as it is occacionally when others havent quite got it right

 

[Foodface]

Ha ha ha, I always seem to start an argument. I thought you had to have the ticket to work and install componants directly to do with the relevant appliance.

 

[Koogatubac]

Lol

 

[mountainman]

I agree with Lame as wrong as it sounds. On both counts

I know that the industry is nuts, but needing G3 to change a synchron motor is truly mad.
I don't mind myself, as I have the G3 ticket but there is so much confusion in the industry that my last two callouts to 'unvented' cylinders turned out to be Gledhill Boilermates. Lol.

 

[Millsy 82]

two port on the coil is a safety device as well on an unvented and part of the system so the rules would say you need an unvented ticket.

Do you need boilers to change an external pressure vessel or prv? No. How is this any different? I agree it is a safety device but you dont need unvented to replace a 2 port valve.

 

[lame plumber]

so you know the hw mv is a safety device and part of the package then and how the rules should be applied.

 

[Millsy 82]

I will do some digging around tomorrow and find the answer. If you are correct then that is just stupid. How can you be able to work on a heating system but not be able to change a 2 port valve?

 

[lame plumber]

because its part of an unvented HW system, its like having to install a 2 port when installing an unvented cyl even though there may be a 3 port valve already in situ, its provided by the manufacturer so has to be installed,

 

[chris watkins]

Strictly speaking the 2 port is not the safety device, it is the over heat (energy cutout) thermostat which provides that function, I agree in most cases it would be linked to a spring return zone valve but this does not have to form part of the system.
This can best be seen in the Vaillant Un-vented cylinder which so long as it is installed & wired to one of their boilers does not have a two port / ECO, this function is accepted as being met by the boilers own high limit stat.

 

[SimonG]

I will do some digging around tomorrow and find the answer. If you are correct then that is just stupid. How can you be able to work on a heating system but not be able to change a 2 port valve?

Doesn't matter if it's stupid (and I do agree) but it is classed as one of the cylinders safety devices. I can see it as another way a manufacturer would try to dodge a warranty call.

 

[chris watkins]

Building Regs - G3
Non-self-resetting energy cut-outs
3.28 Non-self-resetting energy cut-outs mayonly be used where they would have the effectof instantly disconnecting the supply of energyto the storage vessel.
3.29 Non-self-resetting energy cut-outs shouldconform to:

1. BS EN 60335-2-73:2003 Specification for safetyof household and similar electrical appliances.Particular requirements. Fixed immersionheaters and BS EN 60730-2-9:2002Automatic electrical controls for householdand similar use. Particular requirements fortemperature sensing control; or
   
2. BS EN 257:1992 Mechanical thermostats forgas-burning appliances.
   

3.30 Where a non self-resetting energy cut-out operates indirectly on another device (seeparagraph 3.18) to interrupt the supply of heat(e.g. it is wired up to a motorised valve or someother suitable device to shut off the flow to theprimary heater), the energy cut-out shouldcomply with the relevant European Standard(see paragraph 3.29) or the supplier or installershould be able to demonstrate that the devicehas equivalent performance to that set out inrelevant standards.
3.31 Where an electrical device is connected tothe energy cut-out, such as a relay or motorisedvalve, the device should operate to interrupt the supply of energy if the electrical power supply isdisconnected.

3.32 Where there is more than one energy cut-out (see paragraph 3.35), each non-self-resettingenergy cut-out should be independent (e.g. eachshould have a separate motorised valve and aseparate temperature sensor).
3.33 Where an energy cut-out is fitted as setout in paragraphs 3.13 a) or 3.18, each heatsource should have a separate non self-resettingenergy cut-out.

Not that clear I know but is the case. I must say I would always have it linked to a 2 port.

 

[kirkgas]

I'm not entirely sure that you need G3 to change a motorised valve as its not part of the 'unvented' side of the system.
As long as the new valve was spring return, normally closed the same as the old one.
It probably only needs a new motor or head and it would be a bit drastic to need the G3 ticket to change either of these.

I would disagree, as the 2 port valve on the cylinder isn't used as a conventional 2 port, it's a safety device which closes if the cylinder picks up excess heat in the flow pipe, so it is very easy for someone not to wire it properly as they would normally expect a valve to be powered on, where as in this case it will power off when the stat picks up the excess heat to stop it getting into the cylinder

 

[Foodface]

Where's Harry Hill when you need him?

 

[kirkgas]

Strictly speaking the 2 port is not the safety device, it is the over heat (energy cutout) thermostat which provides that function, I agree in most cases it would be linked to a spring return zone valve but this does not have to form part of the system.
This can best be seen in the Vaillant Un-vented cylinder which so long as it is installed & wired to one of their boilers does not have a two port / ECO, this function is accepted as being met by the boilers own high limit stat.

But if the original system has a 2 port it is part of the safety device procedure and has to be kept, and as its part of the original package you should have the G3 ticket to exchange it

 

[BN9Pete]

:boxing_smiley:

Where's Harry Hill when you need him?

very good

 

[Bunker]

Staggers me that the Megaflows have a sticker on the side explains to the custard how to re charge the air. I'm doing my ticket in October just so I can service them legally/ responsibly

 

[BN9Pete]

I did my unvented ticket in 1995 CITB it has no expiry date on card,i avoid uv systems now as I am told its now out of date, is this correct? thanks Pete.

 

[Mike Jackson]

The regs changed about 6 years ago.

 

[chris watkins]

I did my unvented ticket in 1995 CITB it has no expiry date on card,i avoid uv systems now as I am told its now out of date, is this correct? thanks Pete.

It was changed from "Ever Green" to renewal (5 years which seems a bit much) because of all the changes to Part G which came in with the new 2010 AD, it now covers vented as well as un-vented so 7 Litre has gone, D1 now 600mm, our favorite is that HepVo traps & connections to soil stacks are allowed, limit on hot water temps to baths of 48 degC to name but a few.
Worth doing the up-date Pete IMHO if you go to a good training centre.

 

[BN9Pete]

thanks for the clear reply chris, I have asked a few other installers in my local merchants and none could give me this answer. may go on up-date if keep getting asked about uv work but most houses I work in don't have uv systems. regards Pete.

 

[kirkgas]

I did my unvented ticket in 1995 CITB it has no expiry date on card,i avoid uv systems now as I am told its now out of date, is this correct? thanks Pete.

Yes, you now need to renew it every 5 yrs