Problem hot water from immersion/boiler

[rflook]

Hi,

My rather old immersion boiler decided to give up the ghost the other day, notifying the household by tripping the switches at the fuse box. I guess it is the heating element as replacing the fuse did nowt. No problems I thought as we have a boiler which can do our hot water for us - right? Wrong.

Turning on the hot water actually turns on the radiators across the house? So reading up a little bit it seems this could be down to the 3 port motorised valve. Thing is I havent got a fricking clue how to use the thing (it has Auto and Man on it). So I decided to try a few hours in each position - which still gave me no hot water - bugger.

So looking at the piping system I tried to figure out the maze of pipes in my airing cupboard, it is like a mensa challenge in there (or at least it is to me). I have taken a photo of the piping to the right of the immersion boiler where the 3 port valve is - to the left of the boiler is another pipe which has feed coming from the cold water tank.

The two pipes which run against the wall are baking hot. As are the pipes coming out of the bottom and right of the 3 port valve. The pipe from the left of it is only lukewarm (would be grateful if someone could explain the purpose of the left pipe, not quite sure why it is there). At the bottom of the image is what I imagine to be the boiler return pipe (the one with the red stop tap on it). My neighbour who used to be a plumber says that hot water should flow from the boiler into the immersion tank providing hot water. Is this correct?

Would be grateful if anyone could provide any guidance here before I go out and spend money on new components.

Thanks in advance

 

[Dan Robinson]

Try here: http://bfy.tw/9M4j

 

[Razor900]

I think you need to find the programmer/time clock

 

[rflook]

Try here: http://bfy.tw/9M4j

Ha, very funny Seriously though - am quite keen to learn for myself and enjoy attempting to fix things first. If I genuinely cannot figure it out then happy to pay someone, but would like to give it a shot myself before I go down that route - you never learn if you just get someone to do it for you.

 

[endecotp]

So you have a gas boiler, but you've previously been using the electric immersion heater for hot water, right? Why?

The control on the valve should be left on "auto" if you want the system to control it in the normal way.

As above, there must be a programmer (timer) of some sort somewhere....

 

[muggles]

You've got a gas boiler and you've been heating your hot water cylinder using electric? That's costing you an enormous amount of money - it's about 3-4 times more expensive to use electric than gas.

What do you use to turn your heating on and off? Can you post a pic of your boiler?

 

[stem]

The odd thing here is that the 3 Port valve when at rest (ie not powered up) defaults to the hot water only position where a spring holds it in place. Unless its jammed, this is where they also end up when they fail. If you can still move the lever when the system is switched off and feel the resistance of the motor, it is not jammed. It should be in the 'auto' position, the 'manual' position is to hold the valve in a central position with hot water and heating ports open when the system is first filled with water.

There may be an airlock in the pipe to the cylinder preventing the water flowing, it appears that your have an air vent, have you opened it to see if water comes out?

Has it ever worked properly?

Has anything been replaced, or altered about the time the fault occurred?

 

[Hugh Jaleak]

The left hand pipe, behind the pump in your picture, where does it go? At some point you will need a flow pipe coming from the boiler, to feed the pump, if an open vented system, this should go up and loop over the Feed and Expansion cistern in the loft, with the pipe to the pump teed off before it gets there.

The gate valve at the bottom of the cylinder, is probably there to regulate the flow from the boiler, through the cylinder. In these systems if hot water and central heating are being called at the same time, the cylinder can take the lions share of the flow until satisfied, and thus the heating takes ages to warm up. Check that valve is actually open.

 

[rflook]

Just wanted to say thanks for all the contributions. New 3 port motorised valve fitted and it seems (touch wood) to be working well. The only question is that when I took the old one out, there were what seemed like 3 washers inside of the motorised valve (they were slightly silicone looking) that were almost totally perished. The installation instructions for the new component didnt mention anything about washers so I didnt bother buying any to put in. Hopefully that wasnt a bad move.

Oh and in answer to a previous question, I always used the immersion because it heated up the water in the tank that much quicker. The boiler approach seems to take about double the time. I didnt realise until now that the immersion approach was primarily for 'emergency' situations.

 

[Hugh Jaleak]

Motorised valve has compression fittings on the water connections, no washers needed. No sure where the bits you describe have come from, but certainly not required in/on the valve!

Cylinder might be the older type that takes a bit longer to reheat from the boiler, but check the gate valve on the return, I set mine about 1/2 open, so the cylinder gets a reasonable share of the flow when CH is on at the same time. Immersion can be used, but as pointed out, cost a lot more to run than the boiler to heat the same amount of water.