Heating oil additives, good idea?

smallblueplanet

Hi

we've had our oil-fired CH from new, for about 17 years. I always have the Grant boiler serviced annually. It's due one this September/October.

We only have a 1200l tank, and over the past few years get 500l purchases at a time. It has never run out, there's always a few cms above the oil outlet. Just recently - last Spring with CH/hot water and over summer with hot water - the boiler has been cutting out randomly, mostly overnight I think. Sometimes for a few days running then other times not for weeks.

Anyway, I wondered if it was worth on its next 500l to put in one of the 'fuel additives' things, or buy fuel with it already added? Would it help or will the service sort it out? I thought I could get the service engineer to add 'whatever' if needed.

Thanks.

dunstonh

It is worth adding fuel additives every few fills.   I fill up three times a year and use the additives in one in three of them.   However, I don't use the additives supplied by the oil company.  It is cheaper to buy them yourself.   You can ask the filler to add it for you if you can't reach up.

Additives may help your problem if it's due to gunk, but they are more about preventing things rather than fixing them.  Some people have reported smoother running after adding them, but the problem is that you will add around 500ml for a 1000 litre useable capacity (1200 is probably closer to 1000 useable).    If you don't put it in before a fill up but put it in after then it is going to take a long time to mix in with the kerosene and work its way through.

Have you checked your oil tank sludge filter?      A boiler engineer should check and clean them each visit, but not all do.   It is something that many people can do themselves easily.     When I first moved into our house, the engineer failed to check the oil tank sludge valve on both of his previous visits.  I then had a fault, and the engineer didn't do call-outs at weekends.  So, I phoned another local engineer who came out.   He fixed the fault and checked the filter.  It was full of sludge and dirt.  He believed the lack of cleaning out in previous services resulted in gunk getting through to the boiler.  Needless to say, the original engineer is no longer servicing ours, and the other one does.

smallblueplanet

Thanks dunstonh.
Indeed what is a 'oil tank sludge' filter!? (Edit: found it, so no, never cleaned!) Our service engineer isn't the most communicative but is good value and relatively reliable so he might have been doing it, but I fear not. Where is the sludge filter to be found?
We're due a fill around the time of the service so I could add the additive myself before the fill, I presume you just pour it in? I would use an amount appropriate to the quantity of fuel oil added. I think I have seen the additive for sale (onAmazon, but I only Googled quickly) but could you suggest a brand that is decent? 

lohr500

I have been using this for a few years now and add the recommended amount with each fill :

https://www.amazon.co.uk/gp/product/B08HLYLFFH


There may be cheaper alternatives out there.

No idea if it does any good, but I never suffered any sooting up issues with our 30 year old boiler and the 18 month old Grant boiler is running fine on it .

I serviced the old boiler myself and made sure to clean both filters in the fuel line. One was immediately after the stop !!!!!! at the base of the oil tank. The other was next to the boiler.


Cutting out could well be a sludged up filter as dunstonh has suggested, or it may need the nozzle replacing and the air mixture checking.

Kiran

smallblueplanet said:

We only have a 1200l tank, and over the past few years get 500l purchases at a time. It has never run out, there's always a few cms above the oil outlet. Just recently - last Spring with CH/hot water and over summer with hot water - the boiler has been cutting out randomly, mostly overnight I think. Sometimes for a few days running then other times not for weeks.

Do you have an insulated tank? I had a problem with water getting into the fuel caused by the warm air condensing on the walls on the tank. This was causing issues with the boiler locking out even though we had fuel. I have to get the tank pumped in that instance. I now check every six months for water in the fuel and as I was advised by the guy who pumped it, turn the boiler off for half an hour after the tank is fuelled to avoid drawing in sludge