right here it goes

[eddiebrown424]

round the exes who complained that her DHW was not working. Greenstar system boiler pressurised system was low pressure so I topped it up. There are 2 dials on the boiler one central heating and one for DHW. Read that the dhw dial only works if there is a diverter valve in the boiler but as there is a three port and two zone valves near the pressurised cylinder I assumed that there wasn't so only the central heating knob would work. The boiler fires fine with this on any setting bar frost stat. there are two danfoss stats and a controller by the boiler but no option for hot water only. I figured if the states were off or less than 10 degrees upstairs and down that the main diverter valve would work however it doesn't. There are TRVs but surely on such an expensive and complicated pressurised system with zone valves there must be a way of having hot water only other than turning off all the TRVs.

Any advice please

Thanks

eddie

 

[lame plumber]

a little knowledge is soooooooooo dangerous try using the programmer

 

[dancinplumba]

a little knowledge is soooooooooo dangerous try using the programmer

Haha proving the point

 

[Ermintrude]

Installer is required to leave instructions.

Sounds a mess, two zone valves and a three port?

Can you see where the fitter left his horse?

 

[SimonG]

Installer is required to leave instructions.

Sounds a mess, two zone valves and a three port?

Can you see where the fitter left his horse?

What you on about? Y plan with second zone and a two port on the unvented hot water as part of it's safety requirements.

Might want to give a little thought before putting fingers in gear.

 

[Ermintrude]

Putting whole arm in here!

If two zone valves assuming CH is over 100m2 system as split heating with one of the zone valves, Unless the 3 port is 28mm would suggest that it's restricting the heat output.

Why would you build in a y plan unless its an old system and you couldn't figure it out? Interlock through a three port then zone valve???? Be nice to fault find on! Always convert to s plan with correct size two ports.

I would check that this is wired correctly.

You should contact a suitably experienced contractor with unvented and part p to inspect as suspect that there are a few crossed wires!

 

[Simon F]

there is a three port and two zone valves near the pressurised cylinder. The boiler fires fine with this on any setting bar frost stat. there are two danfoss stats and a controller by the boiler but no option for hot water only.

lets get some clarification here, are you saying it is an unvented HW cylinder
or do you just mean an expansion vessel for the CH system??
boiler works, therefore this is a control issue.
is there an immersion heater that has been heating the water and is now broke, has the boiler ever heated the water??
is there a cylinder stat?
usually the problem will be a faulty zone valve.
post some pictures of the pipework and valves

 

[stevetheplumber]

got to agree with zebadee here i would always go for the s plan as one valve usually comes with the cylinder

 

[eddiebrown424]

nope its defo a pressurised cylinder it just looks like there are three stats and no programmer. there is an immersion as a back up and wht I eant was that there are two one valves one for upstairs and on for downstairs. It seems a really complex system for a three bed council house.

 

[Ermintrude]

Where is picture?

 

[Leo21]

Putting whole arm in here!

If two zone valves assuming CH is over 100m2 system as split heating with one of the zone valves, Unless the 3 port is 28mm would suggest that it's restricting the heat output.

Why would you build in a y plan unless its an old system and you couldn't figure it out? Interlock through a three port then zone valve???? Be nice to fault find on! Always convert to s plan with correct size two ports.

I would check that this is wired correctly.

You should contact a suitably experienced contractor with unvented and part p to inspect as suspect that there are a few crossed wires!

not doubting your knowledge, but your attitudes not good is it!

 

[Ermintrude]

Ay? Attitude? Sorry if I seem a tad frank but that's me. I'm straight up 100% of the time.

 

[eddiebrown424]

will have to get some pics forwarded zebedy she is the ex so don't spend a lot of time around there lol. I don't think it is a piping issue as it all makes sense. I just can't fathom out how you have DHW only as it looks like three stats and no programmer but there must be a way of choosing this option. It's a council house so a man from T. Browns will come and do it it just bugged me as a plumber that I couldn't resolve the issue although i didn't stay long and should have downloaded the stat literature I guess.

 

[AWheating]

if its an unvented cylinder it must have seperated controls for the hot water and there must be a 2 port on the hot water side. So its either dangerous or not the system we think? pictures would help.

 

[eddiebrown424]

Hi thanks will try to get some. Out of curiosity (lucky i don't have a cat) why does an unvented cylinder need a two port on the hot water side. And what is meant by seperate controls.

Thanks eddie

 

[R1CKY]

Hi thanks will try to get some. Out of curiosity (lucky i don't have a cat) why does an unvented cylinder need a two port on the hot water side. And what is meant by seperate controls.

Thanks eddie

Unvented cylinders require a physical restriction on the primary circuit in the event of an overheat, a three port valve can not provide this as they rest open on the hot water port. A motor open, sprung return 2 port valve is required, when the overheat stat triggers, it cuts the power to the valve and it closes itself.

Separate controls means it must have a dedicated time and temperature channel for the hot water. I.e a timer and cylinder stat (with built in manually resettable o/heat cut out).

 

[eddiebrown424]

why thank you learn some on here.. Does that mean that all un-vented are s-plan.

Thanks again

 

[R1CKY]

Not necessarily, some may have a three port with a two port fitted after, but to me that says the installer was lazy/not confident at wiring. But they all should have a 2 port, powered via a cylinder stat with a manually resettable overheat cut out.

Yours should have one, checked it hasn't tripped. If it has, you should get it seen to by a plumber qualified to work on Unvented Cylinders.

 

[SimonG]

but to me that says the installer was lazy/not confident at wiring.

Or in majority of cases, cust too tight to have it done 'properly' via s plan

 

[R1CKY]

More than likely! Personally I wouldn't give them the choice!

 

[SimonG]

More than likely! Personally I wouldn't give them the choice!

Unfortunately sometimes it's the difference between working or not.

 

[Ermintrude]

Do it right or just don't bother.

 

[SimonG]

Do it right or just don't bother.

Alright for you perhaps, but what's wrong with 3 port and 2 ports being utilised. Yes it's not ideal but it would work.

Yes it 'appears' as though you know your stuff, but seem to be a little missing on the practical and common sense required in the 'real world'.

 

[Ermintrude]

In the real world I supervise the jobs and replace shoddy work all day long, correct other people shortcuts at customers expense. 22mm 3 port limits the throughput of system and makes difficult to identify problems. All it would take is 3 bits of tube and a tee! Not like that's going to loose you the job is it?

 

[Leo21]

So you don't actually have to price for work and get it then? And make it pay.

 

[Ermintrude]

I'll back off and let you make what assumptions you like and excuses for doing a poor job just to make a quick buck!

 

[lame plumber]

still reckon he needs to hunt out the programmer, its got to be somewhere

 

[Leo21]

I'll back off and let you make what assumptions you like and excuses for doing a poor job just to make a quick buck!

Why thank you kind sir! I'm up for a quick buck anytime.

 

[Dotty]

Thank you for editing the rude word out Leo.

However, everyone wind their necks in now please before I turn into a Stroppy Croppie!

 

[Leo21]

Thank you for editing the rude word out Leo.

However, everyone wind their necks in now please before I turn into a Stroppy Croppie!

Just stroppy Croppie? Or the I'm on call stroppy Croppie, that one scares me!

 

[Dotty]

That was two hellish weeks of sobriety. Scared me too.

Life became crystal clear with no warm fuzzyness.

Didn't like it at all!

 

[Leo21]

Definately wouldn't describe you as warm and fuzzy over those two weeks. We were all on out tippy toes!