Can anyone explain my heating system to me? Seems to be a mix of immersion heater and

chrisgeller

Hi there,

I’ve just bought a new flat and I’m trying to get my head around the heating system – want to make sure I test it before winter and don’t pay a bomb unnecessarily!

In the heating cupboard there seems to be a combiboiler, and what I think is a pressurised hot water storage tank.

The combiboiler is a Valliant, I can’t see a model number on it anywhere, but I’ve attached a picture below.

The hot water tank is marked as a Ariston STI 150 Indirect – which as best I can tell from their website is a pressurised storage heater. The label also says ‘immersion heater’, but that seems to contradict the Ariston website.

I thought the point of a combiboiler was that it could produce hot water on the fly, and so I wasn’t sure what the point of the hot water storage was at all.

jalexa

chrisgeller wrote: »

The combiboiler is a Valliant, I can’t see a model number on it anywhere, but I’ve attached a picture below

Not a "trick question but how do you know it's a "combiboiler" if you can't see the model number?

And bigger pics pls.

chrisgeller

jalexa wrote: »

Not a "trick question but how do you know it's a "combiboiler" if you can't see the model number?

And bigger pics pls.

Hey - thanks for the reply. I only thinks it's a combiboiler as our surveyor seemed to think it was one - not on any stronger basis than that!

You can click on the pics to make them bigger.

jalexa

chrisgeller wrote: »

You can click on the pics to make them bigger.

Nope, not working. Suspect you have only saved thumbnails. Only 6kB.

HappyMJ

chrisgeller wrote: »

Hey - thanks for the reply. I only thinks it's a combiboiler as our surveyor seemed to think it was one - not on any stronger basis than that!

You can click on the pics to make them bigger.

It's not a combi boiler.

chrisgeller

HappyMJ wrote: »

It's not a combi boiler.

Ah,

The links are here:

http://imageshack.us/photo/my-images/692/valliantcloseup.jpg/

http://imageshack.us/photo/my-images/843/heatingsystem.jpg/

So if it's not a combiboiler - what is it?

HappyMJ

chrisgeller wrote: »

Ah,

The links are here:

http://imageshack.us/photo/my-images/692/valliantcloseup.jpg/

http://imageshack.us/photo/my-images/843/heatingsystem.jpg/

So if it's not a combiboiler - what is it?

You have an unvented system boiler or a conventional boiler. Combi boilers do not have tanks. Vented systems like mine also have a cold water header tank.

chrisgeller

HappyMJ wrote: »

You have an unvented system boiler or a conventional boiler. Combi boilers do not have tanks. Vented systems like mine also have a cold water header tank.

OK - thanks - that makes sense - I don't know where an cold water header tank could be, so it must be an unvented system.

Can these create hot water on-the-fly? There's a little interface (a British Gas UP2), that shows the system is heating water for two hours in the morning before we get up. Does it need to do this?

jalexa

chrisgeller wrote: »

OK - thanks - that makes sense - I don't know where an cold water header tank could be, so it must be an unvented system.

Can these create hot water on-the-fly? There's a little interface (a British Gas UP2), that shows the system is heating water for two hours in the morning before we get up. Does it need to do this?

Judging by the expansion vessel, the hot water cylinder is *probably* unvented. Judging by there being two zone valves and a hint of boiler connections at the foot of the cylinder the cylinder is *probably* heated by the boiler.

Ideally you should have a "programmer" (or time clock) somewhere, ideally a 2 channel one giving independent control of the central heating and hot water.

Might be your "UP2" though I'm not familiar with that model.

HappyMJ

chrisgeller wrote: »

OK - thanks - that makes sense - I don't know where an cold water header tank could be, so it must be an unvented system.

Can these create hot water on-the-fly? There's a little interface (a British Gas UP2), that shows the system is heating water for two hours in the morning before we get up. Does it need to do this?

No... and Yes...

Have you turned the immersion off? I'd turn it off it is on. If the hot water runs out then electricity will be used to top up the heat if the timer is not allowing heat to be provided to the cylinder. 2 hours is about right. Then just test it. If you run out of water then program another short timing period in the evening.

chrisgeller

jalexa wrote: »

Judging by the expansion vessel, the hot water cylinder is *probably* unvented. Judging by there being two zone valves and a hint of boiler connections at the foot of the cylinder the cylinder is *probably* heated by the boiler.

Ideally you should have a "programmer" (or time clock) somewhere, ideally a 2 channel one giving independent control of the central heating and hot water.

Might be your "UP2" though I'm not familiar with that model.

Hi Jalexa - thanks so much for your reply. Can you tell me what the zone valves are that you can see? I didn't spot those.

I think that is what the UP2 does - it has separate controls for hot water and central heating - but presumably this set up of boiler + tank is producing all the hot water to feed both?

Is there any way to tell if the cylinder is making hot water using electricity?