Glow worm space saver constantly heating hot water

[Chrispee]

I have what looks like a very old Glow worm spacesaver in my flat (first time buyer) and have suddenly noticed despite not switching the hot water on for weeks the tank stays hot. When i look at the boiler i have noticed the flame is constantly lit, despite turning the hot water tank thermostat down (was only at 50 anyway) it has what looks to be a 3 way valve, but i dont know if this is the issue, would appreciate any advice as to why the gas is constantly on and likely costing me a fortune!

Much appreciated!

 

[Riley]

Likely that one of the controls on the system is on the fritz. Best to get an engineer out who should be able to sort it fairly painlessly. Don't turn the hot water cylinder stat down as this will result in legionnaires when the constant heating issue is resolved. My suggestion would be the three port valve, one of the micro switches are likely stuck and as such is constantly calling for heat

 

[Chrispee]

Ok thanks, should i be concerned that it's constantly on and keepinhg the tank hot at the moment? The 3 way valve is set to the "open" postition, though may not be working properly either.

Thanks

 

[Riley]

Well your concerns are that the water maybe getting to a temp in excess of what the cylinder stat says. In addition whilst the boiler is firing you'll be paying for it

 

[Last Plumber]

You haven't left the immersion heater on and been looking through the sight glass at the pilot flame have you ?

 

[Chrispee]

To my untrained eye the immersion heater switch is definitely in the off position..unless its wired the wrong way round. I havent had it switched on since i moved in. I assume it wound sound like a kettle element when keeping the water warm and the hot water tank never seems to be making a noise like that.

 

[Last Plumber]

Not always noisy no !

if you turn boiler stat off does boiler flame go out ?

 

[Last Plumber]

theres either two or four pipes above the boiler

Are any of them hot ?

 

[Chrispee]

I see 3 pipes above boiler, 2 are hot one is not.

Rotated dial on what i assume is boiler thermostat all the way round to zero and flame did not go out (only left it here for a second or two) before rotating back to min

 

[Riley]

When you say flame do you mean the burner is on? Someone mentioned this earlier. Or is it just the pilot light?