Need to have kerosene filtered - any advice?

KittenChops

Hi all,

Short story - we've been advised that there's most likely sludge in the oil tank & we should get it filtered - does anyone have any advice / recommendations for getting this done please?  We're in the Midlands.

Edited to add - we also need the oil tank cleaned to remove any sludge in it



Longer story below for context...

We moved into a property about 18 months ago where the heating & hot water use kerosene (no gas connection).  The house had been empty for several months, so during the conveyancing we were told the tank was virtually empty, so with the vendor providing access, we had an oil delivery a few days before completing on the purchase.
Heating / hot water worked perfectly until our second full day in the house, when we woke up to snow & the external oil boiler (installed Feb 2019 by previous owners) not working.  Had someone look at the boiler, think a new, larger burner was put on (can't remember exactly now).  Signed up to a local company who have been out numerous times both that winter & the last, every time it stopped working, the temperature at night probably went down to -10c or colder.  One time they were out trying to defrost the oil in the pipe with my hairdryer (pipes have since been lagged).
So when it happened last (thankfully this winter wasn't as cold as the last, so fewer call outs), the suggestion was that we should have someone come out & filter the oil. They replaced the filter around that time (I thought that should be done at every service?  It was serviced Aug 2022 before we purchased & we had it serviced Aug 2023).
In case it's relevant, in our survey, the tank was flagged as not meeting current regulations (no bunding, next to fence & shed) - I don't want to pay a call out fee & then get told they won't do anything because of that.  Long term plan would be solar (south facing roof at the back) & heat pump but we're a long way off being able to fund that.

CliveOfIndia

This is the sort of thing any decent heating engineer should be able to do (just make sure they're OFTEC registered).  If you have a local community Facebook page, ask for recommendations on there (don't just go for someone who's advertising, ask other local residents for recommendations for someone they've used and can recommend).

In my area, where everyone uses oil, there's 3 or 4 local independent plumbers/heating engineers who everyone uses.  They never advertise, they get more work than they can handle just from word-of-mouth recommendations.

That, actually, is the only down-side - they're so good and charge such reasonable rates that they're always snowed under.  To be fair, they do try and prioritise emergency work, but you often have to wait quite a while for non-emergency stuff.

Jaybee_16

CliveOfIndia said:

This is the sort of thing any decent heating engineer should be able to do (just make sure they're OFTEC registered).  If you have a local community Facebook page, ask for recommendations on there (don't just go for someone who's advertising, ask other local residents for recommendations for someone they've used and can recommend).

In my area, where everyone uses oil, there's 3 or 4 local independent plumbers/heating engineers who everyone uses.  They never advertise, they get more work than they can handle just from word-of-mouth recommendations.

That, actually, is the only down-side - they're so good and charge such reasonable rates that they're always snowed under.  To be fair, they do try and prioritise emergency work, but you often have to wait quite a while for non-emergency stuff.

Agree with this. When my pipes froze 18 months ago he was here until after 7pm on a couple of evenings, firstly to help unfreeze and the second visit to check everything was fine and no leaks.

When I had a slight oil leak, he asked if he could come round to look at it on a Sunday evening.  All at no premium rate charge.

I found him by posting on FB asking for local recommendations.

KittenChops

Thank you both - good advice - I'll let you know what happens...

In the meantime, if anyone has any idea of cost for this (filtering oil & cleaning the inside of the tank to remove sludge), I'd be very grateful

Kiran

The "sludge" will likely be at the bottom of the tank and be caused by moisture in the fuel. A tank with empty space is prone to condensation. Its essentially the same thing a diesel bug. When your fresh oil was delivered it will have mixed up all the old fuel, water and sludge in the bottom of the tank and that will have been pulled through into your fuel line. That is likely why the boiler conked out just after you moved in. I've had similar issues, We moved onto an old farm and the previous owner didn't look after anything. We had a 24 year old boiler so I became very accustomed to how they work and mixing them. One of the things was sludge in the fuel line. This part can be done DIY if your happy to give it a try. I connected a Schrader valve to one end of the oil line and the other end into a old oil jack and blew the line through with a compressor. You can use a car/bike pump but I had 80-90m run. I had to refill the line with oil a couple of times but it went from dirty brown sludge to lovely golden fuel. No issues with the fuel since then. I've replaced the boiler since and have used tank sponges from the fuel tank shop to absorb the water and sludge from the bottom of the oil tank and these seem to work very well. You can get a kit to test for water in your fuel which will let you know when you need to use the sponges. The dry areas of the tank are unlikely to need any cleaning as it should all be at the bottom below the fuel. If you want to get the pros out they basically pump your fuel our of the tank into a holding container via a series of fuel filters. Once it's been through they'll pump the cleaned fuel back onto the tank. Depending on the volume of oil it seems to cost between £3-500 

KittenChops

Kiran said:

The "sludge" will likely be at the bottom of the tank and be caused by moisture in the fuel. A tank with empty space is prone to condensation. Its essentially the same thing a diesel bug. When your fresh oil was delivered it will have mixed up all the old fuel, water and sludge in the bottom of the tank and that will have been pulled through into your fuel line. That is likely why the boiler conked out just after you moved in. I've had similar issues, We moved onto an old farm and the previous owner didn't look after anything. We had a 24 year old boiler so I became very accustomed to how they work and mixing them. One of the things was sludge in the fuel line. This part can be done DIY if your happy to give it a try. I connected a Schrader valve to one end of the oil line and the other end into a old oil jack and blew the line through with a compressor. You can use a car/bike pump but I had 80-90m run. I had to refill the line with oil a couple of times but it went from dirty brown sludge to lovely golden fuel. No issues with the fuel since then. I've replaced the boiler since and have used tank sponges from the fuel tank shop to absorb the water and sludge from the bottom of the oil tank and these seem to work very well. You can get a kit to test for water in your fuel which will let you know when you need to use the sponges. The dry areas of the tank are unlikely to need any cleaning as it should all be at the bottom below the fuel. If you want to get the pros out they basically pump your fuel our of the tank into a holding container via a series of fuel filters. Once it's been through they'll pump the cleaned fuel back onto the tank. Depending on the volume of oil it seems to cost between £3-500 

@Kiran
Thank you for this :-)
Totally get why the sludge is there but great to know the correct process for getting it out!  And I agree, all of our boiler problems most likely come down to this. Looking forward to getting it sorted out (we'll get someone in to do it, this is not something we'd be comfortable doing) & not having anxiety come the winter!

lohr500

I was going to suggest a DIY approach, but then decided against it !!

Once the tank/sludge has been sorted, do consider using a regular fuel additive with each delivery.

I've been using this for years and every time we get the boiler serviced the engineer comments about how clean the combustion chamber is. 

https://www.hydra-int.com/heating-oil-additive.html

Available on Amazon as well.

Given the cost, it isn't a fortune and it certainly doesn't appear to do our system any harm.

KittenChops

lohr500 said:

I was going to suggest a DIY approach, but then decided against it !!

Once the tank/sludge has been sorted, do consider using a regular fuel additive with each delivery.

I've been using this for years and every time we get the boiler serviced the engineer comments about how clean the combustion chamber is. 

https://www.hydra-int.com/heating-oil-additive.html

Available on Amazon as well.

Given the cost, it isn't a fortune and it certainly doesn't appear to do our system any harm.

  Yep, we definitely don't have the skills or the confidence to do it ourselves (I'm imaging an environmental disaster in our garden just at the mere thought of it!) 
We have ordered the additive with subsequent deliveries but it's probably akin to polishing a proverbial erm... "thing" (!) until the sludge is removed.
Thanks for the reply @lohr

We still have quite a bit of oil in the tank from a Jan 2024 delivery, so based on a previous comment (more oil = more cost), we think it's best to wait until later in the year, but I will start ringing around well in advance.  Will update as & when in case it's helpful to someone else.

Kiran

You could definitely do the tank sponge in the meantime What is a Tank Sponge and How Does It Work? (compassfuels.co.uk) That's easy DIY and may resolve, but certainly wont hurt the system 

lohr500

No harm in trying a tank sponge. But if your tank is badly contaminated with water and sludge, a single tank sponge won't make much difference.

The one in the link above will only absorb 700ml of water which is hardly anything.

Imagine if your tank was bone dry and you poured a litre of water into it. That amount of water would barely cover the base.  

Kiran

lohr500 said:

No harm in trying a tank sponge. But if your tank is badly contaminated with water and sludge, a single tank sponge won't make much difference.

The one in the link above will only absorb 700ml of water which is hardly anything.

Imagine if your tank was bone dry and you poured a litre of water into it. That amount of water would barely cover the base.  

They come in 1.5L sponges, the link was just an example of how they are used. If the tank is being emptied, especially in warm weather you'll get more condensation build up in the tank. The outlet for the tank isn't on the bottom, its raised up slightly, so as the condensation level increased the water at the bottom of the tank will increase. Once it reaches the outlet you'll be pulling water into the boiler. Just my opinion, but it would be worth the investment in a few sponges to avoid the boiler breaking down. When we had the issue with our old system, the guys who filtered our oil pulled out just under 4L so this would have definitely prevented the boiler breaking down during the cold weather.