The fourth hole

When we left our heroes, they were just finishing off the third hole and about to put the pipe down it. We thought we were almost done with the drilling.
But, what happened next was that as the drillers were feeding the pipe in, at about 90 metres, they hit an obstruction. They started pulling the pipe back out again with the intention of re-boring the hole with the drill but when they started pulling the pipe out it caught on another obstruction. They tried everything to get the pipe back out again including tying it to the drilling rig and pulling it out that way but eventually it just snapped. I assumed that they might be able to clear out the pipe with the drill but apparently the plastic is so robust that the drill would just have bounced off it.

Feeding the pipe down the hole

trying to pull the pipe out again with the rig

The only option was to drill hole number four. We had a long debate about where to put this and eventually agreed that putting it on the lawn was the best option. Or maybe the least worst option.

Thankfully the fourth hole went very quickly and smoothly (although it also required a significant amount of casing - in this case around 35 metres) and they were finished it in a day and half.
We were pretty nervous about having the rig on the lawn not so much because of the mess it would make while drilling but because it might churn up they lawn while they were driving it on and off, and also having to have trenching across the middle of the lawn.

Moving the rig off the lawn once the drilling was finished

Knowing how nervous (precious?) were were about the lawn, the guys were very careful when driving the rig off. The mess left at the hole and over the lawn was absolutely minimal.

So, the drilling that was supposed to take four to five days has actually taken two weeks which was a bit of a pain but no more than that. We felt sorrier for the drillers who were completely gutted by what happened with the third hole, given they were so close to getting it completed.
It's also worth mentioning that the guys operating the rig were really good to get on with and very focussed on getting the job done. They also didn't mind us prancing around taking photos of them all the time and asking daft questions about what different bits of kit did.
I'm expecting we'll now have a short hiatus while we sort out getting a 3-phase meter put on the house. We already have a 3-phase supply so it should be a straightforward operation but requires Scottish and Southern to come out and do it so we're not holding our breath. Once that's done, we can get the trenching and groundwork done to get the pipes into the house, and then get the heat pump itself installed.
In the mean time, the in-laws and lack of oil are getting closer and closer. There's a sense of inevitability about the two coinciding.

Second and err... third holes

The following are various photos from the drilling of the second and third boreholes.

The observant amongst you will have spotted that we were only supposed to be having two holes drilled, but part way through drilling the top part of the second hole, the casing cracked. The drillers tried to continue with it and spent half a day trying to force more casing down despite the crack, but eventually they gave up on that hole completely, moved the rig a couple of metres and started a third hole.

This third hole has now been fully drilled and just needs the pipes and pressure testing done on it, so all the drilling gear should be gone tomorrow. The estimate was originally that they'd be here for four days which looks like it's going to be more like seven and a half.

In other news, the electrician was in today checking that we really do have 3-phase electricity to the house (we do) and the plumber was also checking a few bits and pieces. We need to get Scottish Hydro out to put in a 3-phase meter which the electrician can then wire up to where the heat pump itself will be.
Before all that happens, there needs to be some trenching dug so that the boreholes can connect to the heat pump once it's in place.
I was hoping not to have to buy any more oil but I know we're getting low and with the in-laws turning up in a few weeks I might have to find out what the smallest delivery is we can get.

Finishing the first hole

The following are photos from when they finished the first hole on Thursday and put the pipe down it that will be used for extracting the heat for the heat pump.

We never quite saw the little blue piece of kit in action so we're not entirely sure what it did but the best guess is feeding the pipe down into the hole but we might be quite wrong with that.

Drilling for real

In the past couple of days they've started drilling for real although it has been considerably slower than expected. I think this is partly because they've had a staff shortage due to the October week holiday, and partly because they had to go down 29 metres before hitting solid rock. This means that every three or four metres they have to stop and weld in another piece of pipe casing which goes down with the drill, slowing the whole process down significantly. Now that they have hit solid rock they're expecting it to be much faster.
The drill causes a bit of vibration and is a bit distracting while trying to work - not dissimilar to having a pneumatic drill nearby.
These are photos taken from the past couple of days.

The drill bit

This is some of the casing being pushed down into the hole with the drill

The first day of drilling

The title on this is a little misleading because in fact no drilling took place because one of the drillers had gone on holiday and the other one couldn't do any more than bring all the kit in and discuss where they are going to drill when the actually do get round to drilling. Anyway, here are some pictures of big yellow drilling things -

The first post

We've teetered on the brink of installing a new heating system almost since we moved into the house but hadn't taken the plunge until now. We inherited a 30+ year old oil boiler with the house. It's been pretty reliable but with the cost of oil having gone up so much (I think it was about 45p per litre last time we bought some) and the boiler probably being pretty inefficient we needed to do something about it.

Our old boiler

The challenge is that the house is quite big, stone built and short of ripping the plaster of the walls, very difficult to insulate. It also has loft-rooms, so insulating the roof is a bit tricky too. We've had all sorts of advice over the years, from those who say that retro-fitting a heat-pump to a house like this will never work because the heat-losses will be too great, to those who say it will work fine.

We currently don't heat the house particularly well, largely because I'm a stingy miser and don't like paying for the oil but, even so, our oil bills were probably somewhere around £1,500 to £2,000 last year. As well as the existing boilder we have two wood-burning stoves, one in the kitchen and one in the living room. We fuel these entirely from wood from trees that conveniently fall down from time-to-time in the garden when there's a strong wind.
In the past year, we've started looking more seriously at replacing our heating system. We've looked at both heat pumps and wood pellet boilers. The wood pellets had some major advantages -

• very low carbon emissions
• a similar kind of heat output to an oil boiler so very much a straight replacement

The downsides with the wood-pellets were largely to do with space: the unit itself is big and we couldn't work out how to fit it into the space the current boiler occupies plus we would have to find space for storage of wood pellets. There was also the issue of having to get the wood pellets from the storage to the hopper of the boiler. Either this would have to be done by hand or an auger would have to be fitted which would have significnatly to the cost.
The other factor in our thinking is that we have the wood-burning stoves and we don't actually like our house to be very warm (probably no more than 15-18 degrees).
For these reasons, we have eventually gone for a 17kW ground-source heat pump. We're aware that this is a bit of a risk given the type of house we live in.
The aim is to get the heat pump in over the next month - hopefully before Winter really sets in. The heat-pump is a NIBE, supplied by EcoLiving. The first step of the installation is going to be drilling two 150m boreholes which should be starting early next week.