Changing to LPG underground tank

collectors

Its surprising what deals come up. About 4 years ago i paid £400 for an underground tank piped up to the wall of the house, but we did all the digging. This was changing from electric to gas. I see about 3 months ago color was doing a free tank, "under or over ground" with you digging out. & the contract prices were good. Its just luck if you manage to get a good deal. Some handy info here on sitting a tank.
https://www.calor.co.uk/media/wysiwyg/PDF/tank_siting.pdf

stubert999

Hi All,

Apologies for what is a long story but a bit of a plea for help / advise.

My partner and I recently purchased in September a new build semi detached property (1 of 4) in Staffordshire that is in a remote off gas village. Effectively every house in the village is therefore on LPG external tanks either above or below ground (ours is below the patio at the back of the house and the other three houses are identical).

The tanks were apparently installed in 2013 before the houses went up and the builder still owns two of the properties and the other two were sold.

We had an issue this winter with the gas supply pressure fluctuating and tripping out the boiler and effecting the hob.

Here starts the major problem...

We call our an engineer to look at the boiler and hob - no issue and it works when the weather is above zero for any sustained period of time - this leads me to inspect the Turret under the patio where the LPG tank and pipe work are as my next guess was a pressure regulator valve freezing up with moisture.... oh dear...

I am shocked to find that the turret is flooded almost up to the bar on which the regulators are mounted... so call Calor and they say thats definitly not normal and an engineer will come inspect.

The engineer has discovered that the builder has essentially not put any drainage in around the tank or turret and has also poured a mixture of cement or other grey flakey liquid into the turret (i assume while completing the patio so it seems to be cement / builders rubble or otherwise). This has covered up the serial number / data plate and most of the top of the tank for a thin layer and initially caused the engineer to worry the tank (usually yellow) had corroded!!!... at one point in this inspection we were condemning the tank and getting all the gas pumped out.

Thankfully he called around and upon scraping a tiny bit of the grey stuff away found yellow underneath it - phew step back from the cliff edge.

Anyway we are now at a bit of an unknown in terms of where we stand, Calor own the tank and the contents under the turret but the builder (private) is apparently responsible for the back filling and adequate drainage - another interesting fact is that the calor engineer said they've seen a fair bit of this in high water table villages like ours (which they advise against fitting tanks in) and that now they physically watch the tank being backfilled (which they didn't do as part of the process in 2013 when ours went in).

The builder claims he was told not to put drainage / pea shingle around the tank because it would cause the tank to become a soak away in itself and all in all doesn't seem too concerned. He has also had to have regulators replaced on the tanks on his 2 properties he still owns so I'm not convinced they're not in the same situation, next door certainly are as we've checked with them.

Given this could be a fundamental water table issue in the winter (there was no water in it in the summer) and Calor's engineer has basically said it will probably be condemned in its current state at its 10 year inspection (2023), we honestly don't know what to do.

My view (an engineer's but not civil or a drainage expert) is that we could put a pipe into the sewer if the water board permit it (which I hear is unlikely), or move the tank or raise it (not a small task - and don't know who'd cop for this, it looks to me like it needs to be around 5-6inches higher)?
I don't see more soak aways working if this is a fundamental water table issue?....

Anyway, long story over, we're hoping calor come back with some paperwork to prove what was and wasn't signed and agreed to at installation but on the off chance - does anyone out there have any similar experience with this kind of issue or suggestions where we could go next?

Many thanks in advance from a sleepless stressed out bloke.

philtrick123

This doesn't sound like an easy fix-
The builder would probably say its installed as the spec at the time, so could wash his hands of it unless you can prove otherwise. Cement around the tank doesn't sound right, they could have used the area as a dumping ground for waste cement during the build.

I think you need to work out the level of your water table. If the regulators are going to be flooded/frozen then you'll have issue. I'm not sure they can seal the turret to the LPG tank to stop water getting in there.
My recent LPG UG tank install has ~12 ton of pea shingle around it. The top of the turret is slight proud of the ground, but if the water table was too high I could see it flooding as the turret is not water tight to the tank.
The only solution might be to raise the tank, and landscape the ground up to the turret. If the water table is low enough you might be able to carefully dig out the earth around the turret and below and install some drainage. All of this time and cost will probably fall on you.

Attached is a link to the Flogas installation guide

https://1drv.ms/b/s!AkxeRAYfHqFlg6ttc338nPzLar2f6w