Boiler not heating water

40wattbulb

Hi,

Our gas boiler will heat the radiators really well but doesn't produce any hot water we have to use the immersion to get hot water

Any ideas why this is so..I am pretty clueless on plumbing:(

Some pics of the immersion are attached

Thanks,
Jerry

delly

Hi Jerry, I will move this post to the plumbing forum, but I will give my own limited idea on your setup.

The white box in the centre of the first picture is whats called a motorised valve. This allow the flow of hot water into your tank. This can work in two ways, the first being that you have to switch the water on on your heating control panel and the blue thermostat pictured has to detect that the water in your tank is cold enough to allow the valve to turn. Meaning if you set the thermostat to only allow the valve to work if the temperature is below 50 degrees and your tank is hot already at 70 degrees then it won't work. So ensure the thermostat is high enough to allow the water in.

You'll know if the thermostat is working as when it is engaged it makes a small ticking noise as it opens the valve. There is usually a manual bar that allows you to force it open if you want to try.

I'll let the experts give you a proper idea now however, as I only know what I do from working with my own heating.

40wattbulb

Thanks for the prompt reply...there is no way to specify hot water or heating at the boiler it is just on or not...see pictures attached

I have put the thermostat down to 0 to try and get only hot water but no joy

If when they heating is on I get no hot water

Any ideas?

delly

Ah, sorry, I should have said. The blue box and dial in the first set of pictures is your thermostat for the water. This should be turned up if you want the water to heat, there should be a click at some point as it reachs the current temperature of your water and once you have set it at a higher number it should kick in.

The thermostat in the second batch of pictures would be for a room and in order for it to work you would have to set it higher then the current temperature in the room it is in. Say around 22 degrees and once the temperature in the room goes past this, the thermostat sends a signal to the motorised valve controlling the radiators in that area to close and therefore stop them heating. The blue stat works in the same way, only it is connected to the tank and if it detects that the water is higher then the temperature you have it set at, it will tell the valve to close and not to send hot water to the tank, In both cases however the heating has to be turned on at the boiler itself to work.

40wattbulb

Hmm I put the thermostat all the way to 90 and turned the boiler on but no joy..:(

delly

I would then try to open the motorised valve manually. At the back of the small white box there should be a small metal bar sticking out. By pushing this over, you are effectively opening the valve, it needs a good push but once open it should allow the water to flow threw. The below link gives a visual of what you should be looking for (The link also tells you how to open your valve, but obviously don't do that as I am only using it to show what you should be looking for).

http://www.plumbteamltd.co.uk/portvalve.html

Pete67

There is an indicator light on the motorised valve - if you turn on the boiler and turn the blue thermostat to maximum does the light come on? If not then probably an electrical problem. You can manually open the valve as above as Delly says. One other thing to check is the red handwheel on the pipe below the white motorised valve - if it's closed you won't be able to heat hot water using the central heating boiler. It should be about 1 turn open, if you open it too much your radiators will not heat when the hot water is heating.

40wattbulb

Hi guys thanks for all the help. I got a professional out this evening..He was able to open up the motorised valve (white box) and force it open

Thanks for the education!