| Archive for Downsizer For an ethical approach to consumption |
| ninat |
question about heating waterWe have oil powered central heating which also does the hot water .The boiler seems to be efficient and the water heats up very quickly. We've managed to cut our usage down to about 1000l per year through the installation of a logburner (sadly doesn't have a back boiler as we are on a pressure system with no coldwater header tank)Our shower is electric, and our new washing machine is cold water, fill, so the only hot water we are drawing off is for dishes. We've a really large well insulated hot water tank which keeps hot for days in the summer so my question is... Is it more efficient to heat the water up once every few days and use until it is all gone or keep it warm by boosting it daily- presumably the thermostat should be set lower if I'm doing this. An ides of thermostat temps would be useful too . Thanks. |
| vegplot |
Generally speaking it's better to heat water on demand when using gas as you're only heating water you use.
I don't know whether it's good for oil fired boilers to be fired up frequently as doing may affect the reliability of the boiler and increase service intervals and therefore costs. If it was a wood burner then it's more effective to fire it once a day and store the heat in large heat store. |
| ninat |
I don't think firing the boiler more often will affect the servicing too much. we have it done once a year anyway for filter changes etc.
I try to make sure in the winter that I'm not firing it up for water alone, but coincide it with the heating being on. |
| RichardW |
With water the hotter it is the more heat you loose.
So its better NOT to keep it hot. Personally with your usage I would make major changes to your system. IE fit an instant water heater. Oh & there are ways of adding a wood stove to a pressured system. Richard |
| Mutton |
Previous house we had an oil combi-boiler rather than a tank so that fired up regularly to do the hot water. Worcestor Bosch one. It seemed pretty good to us apart from the odd times that the valve failed to switch over between hot water and central heating. It would stick with dirt in it or scale. Just a few times a year. We learnt that lifting the lid on the boiler and whopping the valve top with an old drumstick while running the tap would clear the valve.
We ran central heating for 3 bed house plus hot water including showers for two off that boiler. The tank was 1200l and my memory is failing but I think it was three tank fulls every 2 years, so 1800l pa. (Two tanks of oil over three years sounds way too economical which is the other alternative offered by my memory.) The washing machine and dishwasher were set to take the cold feed off the hot water as we'd had a solid fuel Rayburn closed fire in the lounge so had more hot water than we knew what to do with when we plumbed them in. We then replaced with the combi-boiler but didn't re-jig the feeds. Anyway, don't see why the oil boiler shouldn't cope with firing up more often. There is a thing with the new gas condensing boilers that they are more efficient when not always starting or stopping (if I remember that correctly) but don't know if that also applies to oil. |
| ninat |
Richard can it be done safely? to fit a logburner to a pressurised system. are there rules and regs to do with it?
i've decided for the time being just to lower the thermostat a bit and heat the water only when it's all finished. We get so used to the convenience of having hot water on tap all the time and don't realise how much energy we are wasting. |
| RichardW |
Yes its safe. You can get a (dunsley) neutraliser here or other items that handle the heat transfer from one item to the other. |
| alice |
We used to have a combined gas CH boiler/solid fuel room heater and back boiler arrangement, where the solid fuel bit was retro-fitted to the GCH.
IIRC, the solid fuel bit heated a shallow tank which sat underneath the main GCH hot water tank - all together in the airing cupboard. As it were. Aaah, those were the days.... our much-lamented NCB coal concession...we were toasty warm 
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| ninat |
Thanks for link Richard but we have a sealed system, so I don't think the neutraliser would work. |
| match |
Slightly off-topic, but you can always divert the cold water that goes into your heating system past anything else that generates heat - if you can increase the temperature of the water going in, then you use less fuel overall heating it up. There are lots of simple (and not-so-simple) techniques for doing this, from home-made solar panels from old radiators, to boreholes using geo-thermal energy. |