Parents have heating oil burner on all day?

buel10

Hi,

My parents, who are retired, live in a rural area in a two up-two down cottage and whilst working on a job near their kerosene tank during the day I noticed that the burner came on for short periods of time over several hours. When I asked why this was, they told me that the water heating is on all day between the hours of 7am and 9pm.

I use mains Calor Gas for my water heating and have it on from 4am to 5am for the morning shower and 4pm to 5pm to keep the water hot for the night (Shower, dish washer, etc).

My parents seem to think that having their water heating on during the day with a thermostat is cheaper that, say, an hour in the morning and an hour in the late afternoon.

Please can someone give me some advice on this as I would like to save them money.

Thank you in advance.

PasturesNew

Tell them to think of it like a kettle. They fill a kettle and put it on, it boils water .... they don't pass by and flick it on every 30 minutes in case they want a hot drink .... only actually having one at bedtime.

Running anything all day just to keep it "up to temperature" will cost more than leaving it off until needed.

Ebe_Scrooge

Excellent advice from PasturesNew - what they're doing is running a tea urn at the church fete, where the water is constantly kept boiling for instant cuppas Convenient but expensive.

One thing I would add, is check the insulation on the hot water tank. Once the water has come up to temperature, if it's not being used then it should remain hot for a good few hours. If the boiler is kicking in fairly regularly, this would suggest that heat is escaping. Getting the insulation improved will save a fair bit of money in the long run, irrespective of whether you're running the kettle or the tea-urn scenario.

Smiley_Dan

Not just the cylinder, but also make sure the pipes are lagged. Heat soon escapes out the top of the cylinder through the pipes, and given pipes are normally copper this soon conducts through the metal into the open air. Fine for space heating, but do you really need space heating at this time of year?

Cardew

This question comes up time and again. It is of course cheaper to have hot water on timed than 24/7.


HOWEVER as long as the hot water tank is well insulated the heat loss is much less than many people realise.


Modern tanks are tested to a British Standard(BS) and the heat loss is typically 1kWh to 2kWh in 24 hours with the water at a constant 65c. You can sometimes see the figure stamped on the tank.


So in practice the cost between hot water on a timer or left on 24/7 is not huge.


It is also pertinent that the heat is not 'lost' for much of the year, as it warms the fabric of the house - which is why many tanks are in airing cupboards.

Chimney_Sweep_3

Heating water to the first 70c can take the most energy keeping it there or slightly above uses very little assuming well insulated this is why for central heating advise is to keep it on constant low setting. This is the advise a plumber friend is always giving and have also been told by BG.

Cardew

Chimney_Sweep wrote: »

this is why for central heating advise is to keep it on constant low setting. This is the advise a plumber friend is always giving and have also been told by BG.

Bet you haven't got that(incorrect) advice in writing from BG.


Why does every BG central heating installation come with a timer, if a constant low setting is recommended?

Smiley_Dan

Cardew wrote: »

Modern tanks are tested to a British Standard(BS) and the heat loss is typically 1kWh to 2kWh in 24 hours with the water at a constant 65c. You can sometimes see the figure stamped on the tank.

So in practice the cost between hot water on a timer or left on 24/7 is not huge.

Those figures make a lot of assumptions, notably that there are no pipes connected (!) and the entire tank is heated.

Therefore, "in practice" you will lose more than that.

Doesn't change the fact that Cardew is correct and you shouldn't be keeping it on all the time, though.

Smiley_Dan

Chimney_Sweep wrote: »

Heating water to the first 70c can take the most energy keeping it there or slightly above uses very little assuming well insulated this is why for central heating advise is to keep it on constant low setting. This is the advise a plumber friend is always giving and have also been told by BG.

Pretty sure this is fundamentally incorrect, and I only did GCSE physics.

The heat loss is proportional to the temperature delta therefore more power is required to heat the tank, or even maintain the temperature, at higher temperatures. The heat loss from the tank will be higher at a higher temperature, so you will need to continually top up.

This is not the same thing as more energy per se, but over a time period that power adds up to wasted energy.

reeac

Smiley_Dan wrote: »

Pretty sure this is fundamentally incorrect, and I only did GCSE physics.

The heat loss is proportional to the temperature delta therefore more power is required to heat the tank, or even maintain the temperature, at higher temperatures. The heat loss from the tank will be higher at a higher temperature, so you will need to continually top up.

This is not the same thing as more energy per se, but over a time period that power adds up to wasted energy.

Quite right [and I have two Physics degrees]. I must admit, though, that our oil boiler comes on for hot water for three periods per day all year round. I guess that at around 6p./kWh it won't break the bank.

Smiley_Dan

I actually moved to using the immersion heater because even though the cost/kWh is slightly under double it only heats 1/3 of the tank, which is enough for us. I reckon we come out ahead as a result.

Plus there are no losses in heating the pipes to and from the tank.