Water in oil tank??

CarPark2

Full details below, but in brief, it looks like there are cracks in our oil tank and we have water in there. We have just gotten 500 L of oil. We are thinking of replacing oil with a heat pump anyway, so don’t want to spend a load of money on a fix.
Is there any way to drain the water and save the 500L of oil?
Is there any way to seal the cracks in the tank (see attached pics)?



Moved into house 2.5 years ago,
It was built in 2005.
Boiler has been working fine and we have serviced it every September. As far as I can tell, it was the boiler that was fitted when the house was built, but house was only used as a holiday home by the original owners, so it probably got very little use.
Boiler stopped working on Thursday . My wife figured the oil was low, so ordered more and asked the delivery guy to bleed the boiler. He did that, and water came out. All in about 1 little of water came out.
Boiler worked after that, but cut out on Friday. We reset the boiler and it worked briefly, but cut out again soon afterwards.
We called a plumber. He cleared the filter and nozzle. Again it worked briefly after that but then cut out again.
He looked at the oil and there still seems to be water in it.
Looking at the top of the tank, there are a few cracks in it. See attached photos.

So it looks like the cracks in the tank are letting in water. I am considering replacing the oil system with a heat pump, so I don’t want to invest a lot in fixing the oil. However, the heat pump system is a big job (might involve underfloor heating etc), so we can’t go the rest of the winter without heat.


What are our options:
- is it possible to seal the top of the oil tank with silicone or something else?
- is it possible to drain the water from the tank without losing our recently bought 500L of oil?

Any advice gratefully received.

macchoille

CarPark2 wrote: »

Full details below, but in brief, it looks like there are cracks in our oil tank and we have water in there. We have just gotten 500 L of oil. We are thinking of replacing oil with a heat pump anyway, so don’t want to spend a load of money on a fix.
Is there any way to drain the water and save the 500L of oil?
Is there any way to seal the cracks in the tank (see attached pics)?


Moved into house 2.5 years ago,
It was built in 2005.
Boiler has been working fine and we have serviced it every September. As far as I can tell, it was the boiler that was fitted when the house was built, but house was only used as a holiday home by the original owners, so it probably got very little use.
Boiler stopped working on Thursday . My wife figured the oil was low, so ordered more and asked the delivery guy to bleed the boiler. He did that, and water came out. All in about 1 little of water came out.
Boiler worked after that, but cut out on Friday. We reset the boiler and it worked briefly, but cut out again soon afterwards.
We called a plumber. He cleared the filter and nozzle. Again it worked briefly after that but then cut out again.
He looked at the oil and there still seems to be water in it.
Looking at the top of the tank, there are a few cracks in it. See attached photos.

So it looks like the cracks in the tank are letting in water. I am considering replacing the oil system with a heat pump, so I don’t want to invest a lot in fixing the oil. However, the heat pump system is a big job (might involve underfloor heating etc), so we can’t go the rest of the winter without heat.


What are our options:
- is it possible to seal the top of the oil tank with silicone or something else?
- is it possible to drain the water from the tank without losing our recently bought 500L of oil?

Any advice gratefully received.

I’m no tradesperson but I’m guessing that sealing the cracks will be a very short term solution. Unless you’re getting your heat pump in the next few weeks I’d be looking for a second hand tank, there’s a few on DoneDeal under 60 euro

CarPark2

macchoille wrote: »

I’m no tradesperson but I’m guessing that sealing the cracks will be a very short term solution. Unless you’re getting your heat pump in the next few weeks I’d be looking for a second hand tank, there’s a few on DoneDeal under 60 euro

Thanks. I presume for a second hand tank, you would need a trailer to collect and still need somebody to fit it etc?

I don’t have the trailer. Any idea how much a new tank delivered and fitted and old tank removed would cost?

Still waters

Use tech 7 roof repair or something similar, brush it on and itll do the job for a long time

sham58107

CarPark2 wrote: »

Thanks. I presume for a second hand tank, you would need a trailer to collect and still need somebody to fit it etc?

I don’t have the trailer. Any idea how much a new tank delivered and fitted and old tank removed would cost?

You should ask your oil dealer to remove the oil, as soon as that tank is not repairable and if left too long it may leak a lot !!

The oil dealer may be able to supply new tank, or any hardware will deliver probably around € 3-400 euro , as someone else said you could probably get second-hand but you want to be sure why it is for sale.

if you change system you just flog new tank

gerard2210

CarPark2 wrote: »

Thanks. I presume for a second hand tank, you would need a trailer to collect and still need somebody to fit it etc?

I don’t have the trailer. Any idea how much a new tank delivered and fitted and old tank removed would cost?

I got an oil tank replaced last summer cost around 500 euro. That involved taking oil out of old tank, fitting new tank and putting oil back in.

DGOBS

Totally agree with above, that tank is in an awful state, especially the first pic assume this is on the tank side.
500ltrs of oil is very heavy, and a tank showing that kind of split could fail at any time

Your oil supplier should not have put oil in that tank in the first place!

CarPark2

gerard2210 wrote: »

I got an oil tank replaced last summer cost around 500 euro. That involved taking oil out of old tank, fitting new tank and putting oil back in.

Thanks. This probably sounds like a stupid question, but did you buy the tank and then arrange fitting separately or did the tank seller do it all or did your plumber buy the tank and manage the changeover?

pablo128

The water will be at the very bottom of the tank. If you get a pipe that reaches the bottom and can draw the water out with some kind of vacuum pump, that might be enough to get you until the summer. In the meantime you could cover the tank with a tarpaulin or something similar.

con747

CarPark2 wrote: »

Full details below, but in brief, it looks like there are cracks in our oil tank and we have water in there. We have just gotten 500 L of oil. We are thinking of replacing oil with a heat pump anyway, so don’t want to spend a load of money on a fix.
Is there any way to drain the water and save the 500L of oil?
Is there any way to seal the cracks in the tank (see attached pics)?



Moved into house 2.5 years ago,
It was built in 2005.
Boiler has been working fine and we have serviced it every September. As far as I can tell, it was the boiler that was fitted when the house was built, but house was only used as a holiday home by the original owners, so it probably got very little use.
Boiler stopped working on Thursday . My wife figured the oil was low, so ordered more and asked the delivery guy to bleed the boiler. He did that, and water came out. All in about 1 little of water came out.
Boiler worked after that, but cut out on Friday. We reset the boiler and it worked briefly, but cut out again soon afterwards.
We called a plumber. He cleared the filter and nozzle. Again it worked briefly after that but then cut out again.
He looked at the oil and there still seems to be water in it.
Looking at the top of the tank, there are a few cracks in it. See attached photos.

So it looks like the cracks in the tank are letting in water. I am considering replacing the oil system with a heat pump, so I don’t want to invest a lot in fixing the oil. However, the heat pump system is a big job (might involve underfloor heating etc), so we can’t go the rest of the winter without heat.


What are our options:
- is it possible to seal the top of the oil tank with silicone or something else?
- is it possible to drain the water from the tank without losing our recently bought 500L of oil?

Any advice gratefully received.

Any water in the tank will settle on the bottom so I doubt the cracks you posted pictures of have let enough water into the tank to get it to the level of the feed out of the tank which is usually about 4 inches above the base of the tank. If you are changing to a new system soon I personally would not be concerned. That is only my opinion though.

10-10-20

You have what appear to be UV induced cracking at the stress-points, mainly on the top mm of plastic and not affecting the underlying layers just yet (as you are not experiencing oil leaks).
I don't see what harm a mastic would do here as the tank is flexible and will expand and contract as the oil level changes. But I'd consider it a short-term fix.
You'd need a mastic which is going to adhere to MD Polyethylene (MDPE), but that's going to be difficult to obtain as PE is pretty resistive to gluing. Still, it could be used to prevent water ingress and let you use up that 500l fill.
The other option would be to plastic-weld the tank with a soldering-iron and some PE as feed-stock. I'd be going down the mastic route, TBF.

con747

I would think there is another problem with the boiler.

jmreire

CarPark2 wrote: »

Full details below, but in brief, it looks like there are cracks in our oil tank and we have water in there. We have just gotten 500 L of oil. We are thinking of replacing oil with a heat pump anyway, so don’t want to spend a load of money on a fix.
Is there any way to drain the water and save the 500L of oil?
Is there any way to seal the cracks in the tank (see attached pics)?



Moved into house 2.5 years ago,
It was built in 2005.
Boiler has been working fine and we have serviced it every September. As far as I can tell, it was the boiler that was fitted when the house was built, but house was only used as a holiday home by the original owners, so it probably got very little use.
Boiler stopped working on Thursday . My wife figured the oil was low, so ordered more and asked the delivery guy to bleed the boiler. He did that, and water came out. All in about 1 little of water came out.
Boiler worked after that, but cut out on Friday. We reset the boiler and it worked briefly, but cut out again soon afterwards.
We called a plumber. He cleared the filter and nozzle. Again it worked briefly after that but then cut out again.
He looked at the oil and there still seems to be water in it.
Looking at the top of the tank, there are a few cracks in it. See attached photos.

So it looks like the cracks in the tank are letting in water. I am considering replacing the oil system with a heat pump, so I don’t want to invest a lot in fixing the oil. However, the heat pump system is a big job (might involve underfloor heating etc), so we can’t go the rest of the winter without heat.


What are our options:
- is it possible to seal the top of the oil tank with silicone or something else?
- is it possible to drain the water from the tank without losing our recently bought 500L of oil?

Any advice gratefully received.

First thing to mention...the water, will all go to the bottom of the tank, as it's heavier than the oil, and they will not mix.
2nd, most tanks (if fitted correctly ) are not fitted truly horizontally....they slope a little backwards away from the outlet tap / valve. The tap / valve will normally be a few inches higher on the tank, than at the very bottom. All this is designed to allow the moisture / water go to the lowest point of the tank, and the oil will be taken from a point higher than the water level. You can get a tube of water miscible paste from any motor factors, this will react to water in any fluid. So you can paint some of this paste on a dip-stick ( or long wooden stick ) stick in into the tank, touching the bottom, and it will show you exactly where the water level ends and the oil level begins.
So you can either transfer all the oil out into a new tank ( ideal solution ) and then dispose of the old tank and the remaining quantity of water / sediment.
Or drain the water and try to seal the cracks in the tank. But it can be very hard to seal these plastic tanks, as the oil tends to eat through the normal sealants, and they will leak again. A replacement non-leaking tank would be the best solution, and as you are planning on changing the heating anyway, it need not be a brand new tank, You will find lots of 2nd hand ones for sale on the internet.

jimf

my biggest concern would be that the tank could split at any moment dumping 500lts of oil

not a mess you want on your hands

con747

jimf wrote: »

my biggest concern would be that the tank could split at any moment dumping 500lts of oil

not a mess you want on your hands

If any of the major cracks are below the oil level that is possible. If they are above it it would be unlikely.

Ghosteen

There's a paste you can get to check if there's water in your tank. Brush it on a stick, dip it in the tank and if there's water it changes colour. Also, this sounds really odd but I just happened to hear it recently and it works for a temporary option. Rub where the crack is with a bar of soap. The person who was told this tried it and it worked!

Ghosteen

That was for oil leaking out of the tank actually

greasepalm

Agreed tank is in a very bad state and an environmental cleanup might be needed.My thoughts might be drain some oil out to lessen the weight into plastic barrels or an old oil barrel 45 gallon drum which can be siphoned out from high up to lower down.

jmreire

BTW, could you post one or two pics showing the entire tank? One showing the complete side, and then one showing each end, and the top of the tank? Would give a better idea how much of the tank is affected? The oil capacity would be helpful information too...if you got 500 ltrs, then how high up in the tank is the present level?

CarPark2

DGOBS wrote: »

Totally agree with above, that tank is in an awful state, especially the first pic assume this is on the tank side.
500ltrs of oil is very heavy, and a tank showing that kind of split could fail at any time

Your oil supplier should not have put oil in that tank in the first place!

All pictures are of the top of the tank. All of the cracks are on the top of the tank. There are no signs of any cracks on the side or bottom of the tank.

con747

CarPark2 wrote: »

All pictures are of the top of the tank. All of the cracks are on the top of the tank. There are no signs of any cracks on the side or bottom of the tank.

I wouldn't worry about tank failing. Get a qualified boiler service person to find why it has stopped working the past few times. No offence to plumbers but most do not specialise in heating systems.

Ghosteen

First thing I'd do is try the paste. At least then you know if there's water in your tank or not.

jimf

con747 wrote: »

I wouldn't worry about tank failing. Get a qualified boiler service person to find why it has stopped working the past few times. No offence to plumbers but most do not specialise in heating systems.

as somebody who does this for a living I would worry its not a job I would be prepared to do with a tank in that state if it fails as the last competent person on site guess whos ass is on the line


as for fixing the boiler it most likely needs a new fuel pump nozzle and hose but only after all the water has been removed from the system


water can easily be removed from the tank with a suction pump saving the oil content but imho that tank has to go asap

sorry op but this is the only safe solution to your issue

con747

jimf wrote: »

as somebody who does this for a living I would worry its not a job I would be prepared to do with a tank in that state if it fails as the last competent person on site guess whos ass is on the line


as for fixing the boiler it most likely needs a new fuel pump nozzle and hose but only after all the water has been removed from the system


water can easily be removed from the tank with a suction pump saving the oil content but imho that tank has to go asap

sorry op but this is the only safe solution to your issue

All of the cracks are on the top of the tank in what appears to be non critical areas, and why would you change the pipe? Also I would expect it needs a full service by a qualified boiler engineer to find what caused the initial problems.

jimf

water in the tank is what caused the problems it has fecked up the fuel pump

new hose needed because it will be contaminated

new nozzle needed for the same reason as hose

also oil line needs to be blown out as a teaspoon of water will contaminate a new pump within 48 hours

and then boiler fully serviced and set up using a flugas analyser

as for tank itself im sticking to my original post

con747

jimf wrote: »

water in the tank is what caused the problems it has fecked up the fuel pump

new hose needed because it will be contaminated

new nozzle needed for the same reason as hose

also oil line needs to be blown out as a teaspoon of water will contaminate a new pump within 48 hours

and then boiler fully serviced and set up using a flugas analyser

as for tank itself im sticking to my original post

I agree with some of your post.

jimf

con747 wrote: »

I agree with some of your post.

thanks I think

what part do you not agree with the tank I suppose

Darc19

Had similar issues, the tank was placed flat and sediment had built up and was causing boiler not to fire.

We put a plank of wood under the outlet end to effectively raise that end by about 3cm.

Haven't had an issue since.

May not be op issue, but would just take a minute to make sure.

greasepalm

cheap.:D

con747

jimf wrote: »

thanks I think

what part do you not agree with the tank I suppose

Yep, the tank. In all honesty the cracks are on the top and the Op just needs to get a few months out of it and it looks like a 900-1000ltr tank with less than 500ltrs in it by now so highly unlikely to fail. The new hose is a bit much. Also the nozzle but that's only about €8 anyway!

jimf

con747 wrote: »

Yep, the tank. In all honesty the cracks are on the top and the Op just needs to get a few months out of it and it looks like a 900-1000ltr tank with less than 500ltrs in it by now so highly unlikely to fail. The new hose is a bit much. Also the nozzle but that's only about €8 anyway!

the nozzle and hose are a must change as well as pump


im not saying the tank will split for sure con but I am saying I would not be prepared to be involved

worst case scenario tank splits dumps oil op has to inform his insurance co who in turn will involve the epa now theres a headache from hell when it comes to oil contamination

they will want to know the all the details etc I would not like them ringing me for my insurers details

Ghosteen

Well that escalated quickly... :pac:

con747

jimf wrote: »

the nozzle and hose are a must change as well as pump


im not saying the tank will split for sure con but I am saying I would not be prepared to be involved

worst case scenario tank splits dumps oil op has to inform his insurance co who in turn will involve the epa now theres a headache from hell when it comes to oil contamination

they will want to know the all the details etc I would not like them ringing me for my insurers details

From your end of things I agree with the tank failing if you done any work on the system. Some of the work you say is needed I wouldn't. That's just my opinion though.

Wearb

I think there is a little confusion here about Jim's (and Dgobs) excellent advice. When he refers to a hose needing changing, it's the short flexible hosing that connects to the burner.



This job has to be done as Jim said or you will be replacing a new pump with another new one in a few days. Not a cheap part.

con747

Wearb wrote: »

I think there is a little confusion here about Jim's (and Dgobs) excellent advice. When he refers to a hose needing changing, it's the short flexible hosing that connects to the burner.



This job has to be done as Jim said or you will be replacing a new pump with another new one in a few days. Not a cheap part.

Dgobs assumed the cracks on the tank were on the side, the Op said all are on the top so I disagree with that but it's all open to any scenario happening with the tank.

John.G

CarPark2 wrote: »

Thanks. I presume for a second hand tank, you would need a trailer to collect and still need somebody to fit it etc?

I don’t have the trailer. Any idea how much a new tank delivered and fitted and old tank removed would cost?

I got a new tank about 1.5 years ago after my 25 year old one split on the top after getting a refill of 750 litres, my own supplier pumped it out for €60, supplied & delivered a new (900 liter) tank for €280 and refilled & credited me for the exact amount removed and also removed the old tank (all for that €280).
In view of the potential risks involved I would most certainly not advise purchasing a second hand unit.

John.G

Ghosteen wrote: »

There's a paste you can get to check if there's water in your tank. Brush it on a stick, dip it in the tank and if there's water it changes colour. Also, this sounds really odd but I just happened to hear it recently and it works for a temporary option. Rub where the crack is with a bar of soap. The person who was told this tried it and it worked!

Hope its not sunlight (soap) as mine cracked due to the constant exposure to sun on the top!!.

jimf

John.G wrote: »

Hope its not sunlight (soap) as mine cracked due to the constant exposure to sun on the top!!.

I think lifebuoy is the soap of choice in cork :p:p

Wearb

jimf wrote: »

I think lifebuoy is the soap of choice in cork :p:p

Get back to work Jim.

jimf

Wearb wrote: »

Get back to work Jim.

home for a quick mug of tae and a corned beef sandwich :o

DGOBS

Con747, that split (NOT A CRACK) in that first pic looks to be roughly the entire width of the tank (I'm glad it's no on the side) but is an indication of imminent tank failure. There is no denying that (would love to see what the tank supports look like, but can only guess)

Any advise on just hang about and wait, use up the oil, and try fill the cracks is madness pure and simple.


Soap to seal a crack in an oil tank was an old trick, as it's about the only thing that will seal given the plastic is impregnated with oil (mastic etc doesn't work)

I did read above some nutty suggestion of 'welding the plastic with a soldering iron'.......ehhhh....NOOO!
An oil tanks ullage space is full of vapour that can ignite (the more empty and oil tank is the easier it it to ignite/explode the vapour)

OP, do the right thing for you, your home and your insurance, get the oil removed from the tank ASAP (your oil supplier may well help you, especially as they will be implicated should the tank fail if they just filled it) in the long run it's the safest and cheapest solution available too you.

DGOBS

Had similar issues, the tank was placed flat and sediment had built up and was causing boiler not to fire.

We put a plank of wood under the outlet end to effectively raise that end by about 3cm.

Haven't had an issue since.

May not be op issue, but would just take a minute to make sure.

This 'tank tipping' now means your tank bottom is completely unsupported and will fail over time.

John.G

Probably not by design but my 25 year old tank was actually inclined very very slightly towards the oil outlet valve and there was practically nil sediment in the bottom when I scrapped it and more importantly never damaged the burner oil pump which is starting its 15th year shortly. I have never let the tank run dry either and I reckon that even relatively few burner resets to try and flood the pump after running out of oil does more damage than a lifetime of normal service. Also there will be at least 75 litres of oil in my present tank when the oil outlet becomes uncovered due to its location so theoretically at least one would need this volume of water to build up before it would cause pump damage and could/can be easily drawn off before it reaches this level, if in fact it ever builds up to this level which is very unlikely to happen due to condensation alone, IMO.

DGOBS

I always leave a water hog in mine and change it out yearly, especially due to summer condensation in a half empty tank.

John.G

OK, maybe I fell for it but what is a water hog??

Wearb

John.G wrote: »

Probably not by design but my 25 year old tank was actually inclined very very slightly towards the oil outlet valve and there was practically nil sediment in the bottom when I scrapped it and more importantly never damaged the burner oil pump which is starting its 15th year shortly. I have never let the tank run dry either and I reckon that even relatively few burner resets to try and flood the pump after running out of oil does more damage than a lifetime of normal service. Also there will be at least 75 litres of oil in my present tank when the oil outlet becomes uncovered due to its location so theoretically at least one would need this volume of water to build up before it would cause pump damage and could/can be easily drawn off before it reaches this level, if in fact it ever builds up to this level which is very unlikely to happen due to condensation alone, IMO.

Plastic tanks don't need a fall to the rear. In fact it voids the warranty if they aren't mounted level.
There's almost no condensation produced in plastic tanks. Also for structural design reasons the outlet needs to be higher than what's needed in a steel tank.

DGOBS

https://www.oftecdirect.com/Shop/BrowseCategory.aspx?ProductID=54
I wouldn't have you on John....

I have seen condensation in plastic oil tanks over the years! (yes its minimal, but it does occur, used to be much worse with steel tanks)
Good tank husbandry.

Darc19

DGOBS wrote: »

This 'tank tipping' now means your tank bottom is completely unsupported and will fail over time.

It's fully supported - a brick wall would need to collapse and it's about 30 meters from the house.

DGOBS

We put a plank of wood under the outlet end to effectively raise that end by about 3cm.

Did this not raise one end of the tank off the support and now essentially only the but end of the tank sits on the support??
Or did you plane a plank of wood the width of the tank to the slope required, that fully supports the tank?

Anytime (which is many) I have seen tank tipping, a plank (or similar) is placed at one end for the tank, raising the tank off the support, allowing it to slope downwards to the draw off.

This is commonly known as tank tipping, and the unsupported tank then as it gets filled deforms, eventually leading to cracking and sometimes failure.

It's fully supported - a brick wall would need to collapse and it's about 30 meters from the house.

So the house is ok, but what about the surrounding land, any open drains, or open water (rivers, streams etc)
A leaking oil tank into a waterway in a school in Galway a few years back caused the water to be shut off to about 15,000 homes while remedial works were carried out.

CarPark2

Thanks for all the advice. I wanted to find out if the crack was a surface crack or went all the way through. I pushed a folded sheet of paper through the crack and it went all the way through and came out smelling of oil.
It was my wife’s idea - I can’t claim the credit!
So regardless of tank failing or not, it will continue to let water in, continuing to need fixing of the boiler.
So I will try to get a new tank. I’ve covered the current one with a tarpaulin for the moment.
Oil supplier say that they don’t supply tanks, so they are washing their hands of it.
We have a guy coming tomorrow, to give us a quote.

In this scenario, will they have a spare tank to pump the oil to, while they swap out our old tank for the new one?

Our ground is fairly water logged at the moment, so I fear it will be a complete mess if they are bringing in heavy machinery.

con747

CarPark2 wrote: »

Thanks for all the advice. I wanted to find out if the crack was a surface crack or went all the way through. I pushed a folded sheet of paper through the crack and it went all the way through and came out smelling of oil.
It was my wife’s idea - I can’t claim the credit!
So regardless of tank failing or not, it will continue to let water in, continuing to need fixing of the boiler.
So I will try to get a new tank. I’ve covered the current one with a tarpaulin for the moment.
Oil supplier say that they don’t supply tanks, so they are washing their hands of it.
We have a guy coming tomorrow, to give us a quote.

In this scenario, will they have a spare tank to pump the oil to, while they swap out our old tank for the new one?

Our ground is fairly water logged at the moment, so I fear it will be a complete mess if they are bringing in heavy machinery.

Should no need for heavy machinery Op. Just let whoever is doing the job your ground conditions.