Combination cylinder question.

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I have a very old combination cylinder in my flat currently that has the very annoying problem of mixing the cold and hot water together meaning the yield is only 50% of a total heated tank. I'm sure its due to the age of the unit which is approaching 25 years.

Will a new combination cylinder fix / drastically improve this issue? A Unvented Cylinder is out of the question due to the sheer cost.
 
not sure what is happening with your tank, unless the cold section is leaking into the hot, under normal use the hot water will heat to the temp of the stat, (usually 65) the hot and cold are seperate, whether the cold water is in the loft or in a tank above the hot wont effect the temp, if the tank is faulty when you change it everything will be perfect, can you describe the fault any other way to ensure we understand what is exactly happening
 
Kirkgas - Im not sure what is happening. I can hear the water mixing though when i use the water from the cylinder. Its like it splashes on top of the hot water from the cold feed. I get around 50L of hot water, then it goes to luke warm, to cold in under 2 minutes and the tank is 110L.

Plumstar Tom - Yes the cost of a new combi is very reasonable, i can get one fitted for £350, a unvented direct cylinder is 3 times more as i need a slimline model.
 
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So would I!!! I would also like to know where he is getting the cylinder from as I will order a truck load!
 
[DLMURL="http://www.discountedheating.co.uk/shop/acatalog/Newark_Combination_Cylinders.html"]Newark Combination Cylinders[/DLMURL]

Personal friend is doing it for me. I trust them implicitly
 
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The thing is, the hot cylinder will only output as much hot water as there is cold water in the storage tank. Check the cold main ball valve is filling okay.

It maybe that you have had a mains pressure reduction for some reason.
Sometimes hot water is supplied not because there is adequate cold stored water, but that when empty main supply through the ball valve had enough pressure and flow to keep a hot flow going.

If you look at a combination cylinder the cold tank or cistern is usually smaller than the hot cylinder part.
 
Have u Tried putting a new immersion in it?
When it is up to temp,before running any hot water off feel the cylinder to see if its hot from the base to the top (of the bottom part of the heater) of the hot cylinder.
It may be your immersion is shot and u have stratification.
Worth checking with it being direct if 1-ball valve is ok
2-Hot water flow is ok
3-only immersion left or the cylinder just doesnt have the capacity u need.
Id say if its only a small fortic combi cylinder u would struggle to fil a bath even with a new one.
Unvented is the way to go you can pick up a u/v cylinder for a couple of hundred quid more and if youve got a personal friend whoose qualified youre sorted.
Combined cylinders are old hat now,but do hav there uses still in certain applications.
Hope this helps,Good luck
Paul

also whatever dhws u choose will fill up with cold water either from a tank or mains during use,its all about haveing enough stored or go instantaniou with either a combi or water heater (rinnai).
 
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Hi Prs

That may be the next port of call, it may need descaling etc. Totally slipped my mind.

Its a very old combi cylinder that's square, haven't the foggiest who its made by, but its got metal corner protectors and what looks like ply to the sides of it all.

The Unvented Direct Cylinder i need is a slimline 450mm wide, the cost is outrageous and my friend isn't certificated. Im looking at neigh on £1200 which i just cannot afford.
 
Think u will find yours is an "elson" water heater. Do you live in a hard water area?
Also if your heater is that old it will be full of sh!?
Take it out, flush it through till water is running clear givit a shake flu**** again.
Then fill it with hot water from an external source and add descaler-leave to work,
Flush again with fresh cold water then fit new ball valve and immersion,but u aint likely to get much more hot water out off it.
What size is it?
only seen em approx 700x600x800mm
If its that old it could just break when u try to get old immersion out!

also same company u used to quote price of new unit sells direct unvented cylinders from 349 up depending on size there 550 dia surley u can accomodate 10cm
 
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Yes, that's it an Elson!

I have a 550mm wide unit, the pipework wont actually go in. I picked up a cheap HS Megaflo new and went to get it fitted and it wouldn't fit as i have a very small airing cupboard which wont expand much, if any at all.

Mine is only 500mm wide. The Model i need needs to be 450mm wide, so its the Range Tribune which are around £550-£650 depending on where you go.

The crap thing is, i had a house fire and my contents insurance renewed 48 hours AFTER it happened so this is screwing with me royally. Would install a Unvented cylinder if i could, everyone wants min of £600 labour and then some, and there isnt much piping to do either as it runs straight to the bath and kitchen taps from the cylinder as it stands.

Silly question

Can i just put in a standard Eco 7 cylinder without a tank thats a direct feed and put a pump on it?
 
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Not much choice then u need to get rid of that elson if u need more hot water,looks like as u first said the combination cylinder is ur best option on your buget. remember to keep it as heigh as u can for hot water pressure,leaving room to get into the tank on top for maintainance.

Cylinders have traditionally gone into cupboards an installer who nows what he is doing would not have a problem with the pipework assuming cylinder fits in.
Also 600 quid plus sounds alot for what is a days work-but its hard to say without seeing the job.
Good Luck hope u get sorted.
 
Just a quick question.

Can i get installed a direct Eco 7 cylinder and attach a pump to it to increase the flow as a viable alternative?
 
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