Oil boiler vs Electric boiler

Discussion in 'Engineers' Talk' started by Peter Alderson, Jun 28, 2018.

  1. Hi
    Can anyone give me some advice on this. I have an oil fired system using an old Trianco Eurostar boiler. It's regularly serviced, works well and is very efficient for its age of circa 20 years. The problem is the oil tank. its steel, also circa 20 years old and beginning to blister underneath where it sits on the piers. Replace it, I thought but not so simple as its tucked against the bungalow in a tight space with no real option of moving it unless I want it stuck in front of my french doors in full view. Also that's not so good if i ever want to build a conservatory on the back.
    A new tank in its current position won't pass regs, but I cant really put it anywhere else. Thought about a new one of the same type and size, with fire proof board round it, also getting a fireproofed tank, but they are big and very expensive.
    So do I stick with it or is it time to say goodbye to the old boiler and install an electric one. We have no gas supply where i live.
    Has anyone had experience of electric boilers, the type that will run an existing wet radiator system plus hot water and are the running costs much greater ?
    Any advice would be much appreciated.
  2. Dam0n

    Dam0n Active Member

    Where abouts are you? I may have a metal one you can have for some beer tokens.

    We had the exactly the same problem and have installed an electric thermal store so no need for the oil tank anymore (which coincidentally is right by the back wall of the house)
  3. I'm in Newbury, but havn't decided what to do yet, another tank by the house won't comply with regs. Whats a thermal store ?
  4. Dam0n

    Dam0n Active Member

    My thinking was you could just replace like for like and no one would be the wiser...


    The one I have installed is an electraflow or something. It has the option to connect solar thermal panels plus a wood/oil burner.
  5. HappyHacker

    HappyHacker Member

    Generally an electric boiler (they are very cheap) will cost more to run than oil, but that may change of course. A thermal store will store heat generated using off peak electricity which is cheaper than normal but if you have an off peak electric tariff then the peak (during the day) costs more than normal. The rule of thumb was that if off peak usage was more than 1/2 total usage it would be cost effective but with the variety of tariffs and suppliers today you have to work it out. The heat store is then used to provide heat to the house via radiators etc during the day.

    To get a properly sized installation you need to find someone who knows what they are doing. Have a look on the web for guidance on the various options.

    I thought that it was possible to get a new oil tank fitted that did not comply if you were limited on space, you need to talk to tank people who will be able to advise you. A new oil boiler will be much more efficient than your current one.
  6. Heat

    Heat Active Member

    You could ask your local building control if the rules could be relaxed for your oil tank. A new plastic oil tank would need to be a bunded type (a tank in a tank basically) to avoid risk of oil leak contamination. There might be some relaxation of rules on positioning of new tank. Normally has to be 1.8m (6ft) from a flue terminal or a roof edge or door or window. Plus 76cm (30”) from anything flammable like a wood fence or hedge.
    The spoilt view from your window won’t be a major factor in replaxing any regs though I would assume
  7. Thanks for the replies above, they are helpful. I have decided to stick with the oil boiler I have for now as it will be less disruption. Incidentally my boiler maintenance man reckons the boiler is 90% efficient even though its 20 years old, and keeps extremely clean too. No ash in it at all when he checked it last. Moving the tank is a problem, not just for the view but because I don't want to rule out putting a conservatory on the back maybe, so I dont want a tank there. I have arranged to have the tank replaced with a high quality, internally braced, single skin steel tank as its the only one that will fit in the required space, it is not near open drains , watercourses etc and fire cladding will be fitted to make it comply. Bunded would be better, but not practical in this situation.
  8. Heat

    Heat Active Member

    Your old oil boiler will not be 90% efficient. Analysers only give an estimated reading and are subject to how the engineer uses them.
    The best possible actual efficiency of the best standard efficiency oil boiler over a year allowing for seasonal changes in weather is about 85%. There would be an improvement on that though if you had a conventional flue pipe internally which the heat ‘loss’ would add greatly to heat inside your home.
    For your old boiler to reach over 80% efficiency it needs to have a flue temperature (heat loss) above boiler of about 200 degrees C or less and the burner has to be burning the oil as efficiently as possible to achieve high Co2 while still burning fairly clean.
    Generally in theory you should save 10% or more fuel if changing to a condensing oil boiler, which may not be a lot on low usage. But a lot of people do find massive savings.
    Grant Vortex oil boiler is my choice
  9. Thanks, must admit I did wonder about the figures. I will bear in mind the suggestions if and when I need to change the boiler but it doesn't seem worth going to the expense at the moment if its working ok. It doesn't seem too bad on cost, I would say a full 1100 litre tank full lasts nearly a whole year for my 3 bed bungalow. In the summer it uses very little to heat the water only and the guage probably drops about an inch a week in the winter months. It would probably be a bit more if we were at home every day, not just evening and weekends.
    Heat likes this.
  10. Heat

    Heat Active Member

    Very astute of you to realise your current oil consumption relating to likely cost of replacing boiler is not much, if any of a saving unless very long term.
    You have about same oil usage of me. Secret is with gas or oil boilers (besides good house insulation) is not to use the boiler on many on/off times. It is first hour that uses most fuel. Each hour after that uses increasing less fuel. Controls help to save oil also (thermostatic rad valves, wall stats etc)
    Heating your hot cylinder just in summer will barely use oil as the boiler will only burn for a very short period in total.
  11. Bob Rathbone

    Bob Rathbone Well-Known Member

    If you don't have mains gas and don't want to use oil, a heat pump is the next cheapest option to run, ground source being the most reliable. Installation costs are high.
  12. That's interesting about the first hour using most, I guess that's logical when you think about it because it has to heat up all the cold pipework as well as get the house temperature up. We have thermostatic valves, and I try to just leave the thermostat on about 20 deg mostly. Occasionally when we go to work and it's freezing I leave it on all day at around 17 deg for the cat, and it warms up better when I get in. I wonder if it would be better in the depths of winter to leave it on low all night as it comes on for only a couple of hours in the winter mornings, then I'm out the door. probably not much in it.
    I notice a difference when it's been serviced and I'm trying to keep the system clean with a fernox TF1 filter which I fitted. My service man reckons a new boiler wouldn't last anywhere near as long as my old one.
    Just something about heat pumps. I would go with the ground source if I had to choose. My neighbour went with air source, I don't understand that. Its trying to heat the house the most when the air is the coldest, I don't get the logic here. Its going to work best in the summer when you don't need it! Great! He has it for about three years now and is on his third unit I think. perhaps the first two were rubbish, certainly I could hear it droning away, really noisy. This last one seems better.
    My back garden is around 22 metres by 18 or so, would that be big enough for the ground pipes ? and I have heard you need a fair old sized pump room.

Share This Page