Electric boiler woes All aspects of plumbing questions and answers, help, tips and information

[heathcote123]

Hi

I have recently bought a house and seem to be learning rather more than I had intended about diy!

My latest woe is the hot water.

There is no gas to the house, just electric. I have a hot water cylinder which has two connections to the mains. One I am told is for ecomomy 7, and the other for an additional boost off economy 7 hours.

The boiler has been unused for 3 years.

Leaving the boiler on (both elements) constantly for a few days gives my luke warm water, and the 'hot' water comes out of the taps very slowly - takes about 15 minutes to fill half a bath.

Neighbour has suggested it may be 'furred'.

Any pointers would be gratefully received. Especially those suggesting quick instant fixes for minimal money!

Cheers

Richard

[johnb]

hi richard two problems i think , is hot cylinder fed from tank in roof it may not be high enough and do you have a 3 way electric valve between boiler and cylinder there should also be a pump is it working,if it is then you may have boiler problem . does boiler supply c/heating does this work all the best john

[DONFRAMAC]

If you have 2 electricity meters, you are still getting some form of economy tariff (Economy7 or Total Heat/Total Control).
Check your bill or phone the billing Co.
To get the best out of these 2-element tanks, you should use the cheap-rate one only thro' the night, and manually select the other when the tank runs cold. (You could use a plug-top timer)
Obviously the elements have to be in working order, and the thermostat also, and have it/them set to 60 degrees.
The last house owner may have used cool water for cheapness.
Raising the height of the header-tank in the loft will increase pressure and flow.
The piping from the top of the hot tank thro' to the bathroom is usually 22 mm, with 15 mm being OK for routing to the downstairs. The feed from the loft to the input to the hot tank needs to be 22 mm.

[zuumah]

Hi,
When you say 'boiler' are you actually referring to the Hot water storage cylinder?

If so, your neighbour may be right. If you live in a hard water area the immersion elements get covered in calcium and the heat is unable to get through to the surrounding water making it very slow to heat if at all!
If you drain your cylinder and take out the heating element you will easily see if it is affected. [sometimes they are so calcified they are distaorted and very difficult to remove] Obviously th edrain point must be lower than the immersion element position

Be sure to totally isolate the cylinder first by turning off the water supply and also the electric supply to it. Also check you have the right tool to undo the immersion head, a the correct replacement element.
r

[DONFRAMAC]

The above advice by "Zuumah", and your neighbour, if found to be the source of the poor heating, won't cure the flow problem when new immersion elements are installed. New pipes to and from the hot tank req.
Also, an eddy-current unit on the main riser, to soften and gradually remove calcification elsewhere in the plumbing. Their is one advertised in this site, at £130, using 2 coils, powered from a mains adaptor --- costs about 10 pence/week to run, and is a DIY fitting job.

[heathcote123]

Thanks for all the replies. It's been a while as I have been discovering the joys of cutting down the jungle in the backyard, and painting, painting, and more painting.

Getting a bit more settled now, so time to focus on this issue and stop having to boil 10 kettles of water for a bath. Had a look at it tonight.

Firstly good news, the hot water pressure just needed on of the twiddly things moved *all* the way. Plenty of pressure now.

Now the bad news.

Firstly, there is no lid on the hot water cylinder (yes I mistakenly refferred to it as a boiler). Just a 6" diameter hole where it looks like something should be.

Next, If I stick my hand in it, theres a solid wall about 6" beneath the surface. I can't see it, but scraping it, it does indeed appear to be a calcium-like deposit. Thing is its completely solid - from side to side of the cylinder. Is there something in there that this has formed on top of, or is the cylinder just absolutely solid with the stuff?

I've tried to drain it by turning a little screw thing that disables the feed activated by the ballcock (excuse my technical terms please :) ), but after leaving the hot taps running for a while its not going down - I think another pipe also feeds it (looks like the 'in' and 'out' pipes are linked?- (maybe I need to post a pic), so think I need to figure out how to the turn the water off entirely.

I'll have a go over the weekend at getting it drained and go from there.

If it is completely solid with the stuff, is it salvagable or am I looking at a new cylinder? - saw some stuff called fernox ds3 which looks suitably noxious, but can it work miracles?

[johnb]

hi heathcote pics would be good john

[heathcote123]

Hi

Did a bit more research, and it turns out its a very old gledhill pulsacoil thermanl heat store, which explains the barrier bit at the top, as it has a small cold water tank on the top, for topping up the main store.

I drained it out, and the elements were indeed furred, so I gave it a load of fernox ds3, which worked a bit, the temperature a flow improved a bit the next day.

Unfortunately though, It would seem that the limescale was the only thing holding it together as it started leaking from the bit where the economy seven element was (I hadn't even touched that bit). I stripped off the cladding, and found that it was completely corroded around that area.

Fortunately I have a couple of weeks off work at the moment :)

I need a new electric hot water system. I have been looking at the eemax series 2. Its a small 2 bed terrace and I'm not really botthered if it can't manage a bath and a sink at the same time - the tech support people seemed to think it would be fine for this. I appreciate that the performance may not be up to a replacement pulsacoil, but I'm thinking *tight* budget here :)

Anyone have any expereince with them?