Unvented Cylinder

[Red]

Hi all,

Its a while since I did my unvented hot water and im not sure what type this is (please see pics)

The customer is looking to replace this cylinder, as im sure your aware modern unvented cylinders require a 22mm mains cold feed, from the pics it looks like this one only has a 15mm feed going to the top section..

I could'nt see a tundish anywhere either?

Any suggestions on what type of unvented cylinder this is?

Thanks

 

[sonray ltd]

if you think this is an unvented cylinder you need to retake your g3.
what ever makes you think this is unvented ?

 

[Red]

The fact that it has no vent, im not sure, thats why im asking, isnt that what the forums for?

Richard

 

[sonray ltd]

i can see the vent.

you can't tell me your experienced & safe with g3 when your having trouble with this cylinder.
don't mean to sound harsh but if this is the standard of the plumbing trade today im disgusted.

 

[Mike Jackson]

Looks like a thermal store to me. Best option is probably to replace it with an unvented if a suitable route for the discharge can be found. 22mm main is recommended for unvented but not essential. It all depends on how many outlets will be used at once.

If your unsure of what it is I would get someone else to take on the job or wait until you have retaken your unvented ticket.

Mike

 

[justlead1]

Hi. You are looking at a combination cylinder. If you lift the ali lid off you will find a ball valve. The top part stores the cold water and is connected to the bottom part via a pipe (internal on some brands) the short pipe covered in foam is the vent. They were used in caravans and small flats as a cheap alternative to the more common CWSC and cylinder arrangment.

The storage of cold water was small, when turning on a bath tap at a lower level, say the floor below the delivery often out paced the storage capacity and mains delivery.

Other issues you need to address are is it indirect or primatic? How is the heating circuit filled? As other have hinted you might not be doing your client justice by undertaking such work with your limited knowledge of hot water systems. Although i would like to help you more, i feel it is work for a more technical plumbing contractor. Good Luck

 

[Red]

Thanks for your more constructive reply's guys,

I did my Unvented 2 years ago and I have been working in new build for the last 5 years only really dealing with combi boilers, Y plan systems and new Unvented cylinders but since the economic slow down I have now moved in to domestic plumbing, I have not come accross one of these before so please forgive my lack of experience but I am competant to install a new system I just want to totally undestand the current set-up.

I have just been back to the customers property to take another look,
After looking at some of my old college paprework it appears to be a combi cylinder (as the latest post also suggests) but there is high pressure hot water at all outlets and no pump (hot water) and there is a 22mm copper discharge pipe running to outside? or is this a overflow for the combi tank?

This is a 4 bed property with 1 bathroom, 1 en suite and a cloak

any info appreciated

Thanks

 

[Mike Jackson]

It's definitely some sort of thermal store. The cold water goes into a coil within the main body and is heated as it passes through. This emerges and is mixed with cold via the blending valve to a suitable temperature. Normally the cold tank on the top of the unit is the header tank for the Primary side but it may not be in this case.

Most thermal stores I have come across are a combined unit with the heating water being drawn from the same unit as the hot water. On this style there are two pumps, one which pumps the primary circuit between the boiler and store, normally on the return and another pump which draws heated water from the store and pushes it round the heating circuit.

This looks as though it may be a separate thermal store heated by a Y plan. If so then it is a piece of cake to convert to an unvented cylinder.

Mike

Have a look at [DLMURL="http://www.newarkcoppercylinder.co.uk/cylinders/thermal_store/"]Thermal Store Copper Cylinders - Newark Copper Cylinders[/DLMURL] . That will give you an idea of what you are looking at.

Mike

 

[Red]

Yes it is definitely a thermal store im sure of that now - thanks

Also I made an incorrect assumption with regards to it being a sealed system. I am pretty sure the small tank on the top is the F & E for the primary circuit as you suggested in your last post,

This is a bathroom renovation the customer wants to move the cylinder location into the loft to use the airing cupboard space to expand the bathroom, they also want the Thermal store replaced.

If the unvented cylinder is installed in the loft obviously there is the problem of getting sufficient head (excuse the pun) for the primary heating system, so would be best to fit a new thermal store rather than converting it to unvented?

Or convert to a sealed system? 2 x 2 ports etc?

Thanks very much for any help

Richard

 

[Mike Jackson]

If possible I would go for a sealed system with an S plan. This would also give greater compatibility in the future when the boiler requires changing.

Mike

 

[justlead1]

Hi. Red i owe you an apology for bum info, it looked like a fortic combination at first glance. Good Luck

 

[Red]

np, thanks anyway,

Well in the end the customer decided to keep the current thermal store set up as the lead time on a replacement was 14 days, also they were not keen on converting to unvented so I relocated it into the loft space on friday morning, the electrician did his part and the system was up and running,

However at first only working on the hot water side (no power to 3port), I manually moved the 3 port over to mid and got heating flow and eventually returning so I am 100% everything is ok on my side of things,

After the sparky changed around the wiring configuration it was running in mid position and then left over night with heating and DHW but the 3 port is not switching over as it should.

Yesterday I supplied some Honeywell wiring diagrams and he tried working to those, apparently the 3 port only has 3 wires and it should have 5, it is a British gas supplied one, after hours of testing he found live was neutral from the boiler, also I obtained a new 3 port (Drayton) which did have the correct amount of wires according to the Honeywell wiring diagram.

When wired it started blowing the boiler fused spur, after trying various tests and wiring setups the system now wont run at all, boiler flashing red (lockout) when calling for heat (Potterton Suprima 60) yes I have been reading how bad these boilers are but it was working fine before..

He has refitted the old 3 port head and it still wont run in mid position as it did at first before... They have had 3 new pcb's from British gas as they have cover.. They are coming out tomorrow...

bit of a nightmare on the wiring side anyway.. I will let you all know the outcome.


Richard

 

[sonray ltd]

this post is beginning to worry me, we now have a sparky that can't wire a valve on a heating system.

>the 3 port only has 3 wires and it should have 5.

i take it someone has nicked two then ?
or more like you can't tell the difference between a diverter valve and a mid position. valve.

>I manually moved the 3 port over to mid.

you will never move a diverter valve to mid position in a million yrs.
so you never moved the 3 port to mid.

>He has refitted the old 3 port head and it still wont run in mid position

you won't get a diverter to mid position ffs.

>bit of a nightmare on the wiring side anyway.

how can it be a nightmare on the wiring.

get yourself a proper elecy who knows heating systems as he hasn't got a clue.

then sit back and think why is the system fitted with a divertor valve in the first place and not a mid position valve.

>after trying various tests and wiring setups the system now wont run at all

why various tests ? wire it right the first time and it will work. don't keep gambling that it might work your in a customers property ffs.

> I will let you all know the outcome

please do i'd like to know how much this customers bill is coming to or why he hasn't chucked you clowns out yet.
-------------------------------------------------------------------- 2 hours later

now the clown decides to send me a private message telling me i don't know what i'm talking about.

i think you look a fool more than me.

a thermal store that looks like a unvented. - i think not so much for your g3.

a motorised valve thats got 3 wires when it should have 5 wires. - not that you don't know the difference between a 3 wire diverter valve and a 5 wire mid position.

a leccy that hasn't got a clue about heating controls.
blown untolled fuse anmd still scratching his head. thats what meters are for to test for faults in wiring, use it.

now lets way up the facts.

1, don't tell me that i don't know what im talking about when i just told
you about your so called unvented cylinder, 3 wire motorised valve
must be new on the market.
a 3 wire diverter valve that you can put in mid position.
and a lecky thats as much help as a chocolate fireguard.

and please don't tell me you have the front to touch gas.

2, if you got something to say say it on here not private mail as i'll
just put it on here. as i don't have to hide my head in shame.

 

[Red]

If you aint got nothing helpful to say dont bother responding to my posts please

try putting that on the forum post.

you got a leccy that can't do heating systems.
both of you can't tell the difference between a diverter valve and a mid position.

er why has one got 3 wire when it should have 5.

you pratt cause its ment to have 3.

you can't tell a thermal store from a unvented.
then still think its a combination.

i think you need to think again not me.

i told you whats wrong sad little man now if you can't addmit it then whos the fool.

I have not said once that you don't know what you are talking about I just don't like your hostile attitude, I simply said to you if you have not got anything helpful to say please don't reply to my posts" and you start getting all mouthy.

Now as I have said previously in this thread I am new to house bashing / maintenance plumbing & heating, I am not an Electrician and it isn't my customer, I have been contracted to do the plumbing side which I have done correctly, it is not up to me which electrician the company hires.

Now as I have already asked you politely please do not respond to my posts as I don't like your attitude, im sure people would rather be reading helpful information rather than you shooting your mouth off.

One more thing, If you spoke to me like that in person you would get a lot more than just a verbal response.

 

[sonray ltd]

you clearly haven't got a clue on unvented cylinder, motorised valves, heating electrics etc.

your just a dreamer your quite free to come and visit us in person.