What could be wrong with my boiler?

jinglejones

I live in a pretty nice sized 3 bedroom home. It has a shower and a cast iron bath. I only moved in back in November, and have found that there is a problem whenever I try and have a bath. Even if I make sure the hot water has been on for hours before I start to run it, the boiler only seems to have enough hot water in it for half a bath's worth. As its a cast iron bath, it loses heat very quickly, so I end up sitting in luke warm water!

Even when I have a shower after 15 minutes or so the water runs completely cold.

Any idea what could be causing this?

clutton_2

is it a combi boiler that heats your water or is it an immersion heater ( comprising of an electric element inside the hot water tank)

jinglejones

Its an immersion. I think? There seems to be two boilers - one in the kitchen that has a pilot light on it, and a a timer beside it where I can pressed hot water boost & central heating boost (as well as putting the timer on so it goes off at night etc) and then there's another big round tank upstairs in the airing cuboard which has lots of padding round it and an immersion bit on the top.

I assume this is the standard set up for the majority of houses, right?

Fire_Fox

When was the boiler last serviced?

G_M

Are you using the boiler to heat the tank, or the electric emmersion heater in the tank itself?

Is there a thermostat on the tank? Usually about halfway up, it should be held against the side of the tank but not covered by the 'padding'.

If you are using the emmersion, sometimes these are quite short, and since they project down into the tank from the top, they may only heat the top part of the tank.

If the thermostat on the side (which controls the boiler) is covered up by the padding it will heat up fast. It will then 'think' the tank is hot and will signal the boiler to turn off prematurely.

Also worth checking what setting the tank thermostat is on (should be about 60). Oh, and also the setting on the boiler itself (might be inside the boiler casing.

Failing all that, see Firefox's post above!

Or try a specialist forum like DIYnot.

LisaLou1982

Is the large tank upstairs insulated? If not, get a jacket for it - it'll keep the water hot for a lot longer

G_M

LisaLou1982 wrote: »

Is the large tank upstairs insulated? If not, get a jacket for it - it'll keep the water hot for a lot longer

Sounds like the 'padding' is insulation.

Agreed you can never have too much of this. As tank jackets are so cheap from B&Q it's always worth adding another.

However even without insulation it's unlikely the tank would cool quite that fast.

silvercar

jinglejones wrote: »

I live in a pretty nice sized 3 bedroom home. It has a shower and a cast iron bath. I only moved in back in November, and have found that there is a problem whenever I try and have a bath. Even if I make sure the hot water has been on for hours before I start to run it, the boiler only seems to have enough hot water in it for half a bath's worth. As its a cast iron bath, it loses heat very quickly, so I end up sitting in luke warm water!

Even when I have a shower after 15 minutes or so the water runs completely cold.
Any idea what could be causing this?

Both coloured phrases suggest that your tank is too small for your needs.

googler

If the tank is smaller than the bath, and you're only heating the water in the tank........

googler

If you've had the immersion 'on for hours', then go to the hot water tank, reach through the insulation, and feel the surface of the tank - if this is hot all the way to the bottom, then good. If it goes cold or lukewarm part-way down, then the thermostat seems to be cutting it off too quickly.

BitterAndTwisted

One of the ways you can preserve the heat in the bathwater is to insulate the space underneath with bubblewrap. You'll need to remove the bath-panel to do this but it can make a huge difference if you fill up the entire space with it.

Good luck with your hot-water problem-solving