Fell Water Supply Project

[jackpreacher]

I bought a Volvo EC15B to complete a water supply project that my farmer neighbour and I started in March 2012.
See here to find out what happened to my EC15B after around 10 hours of use. It pushed back this whole project by 4 months.

Anyway, all that is in the past and 'Doug' is working as well as he should be mainly because of the first rate help and advice I got from this forum - once again, thank you all very much.

Right, enough of the touchy-feely stuff before Stock has a go at me.................


Objective of this project:

1. Remove 800m of dilapidated Victorian 2" pipework from the fell behind our property. This has been the fresh water supply to our property, and neighbour, since time immemorial.
2. Replace the old, corroded and blocked iron pipe with 2 off MDPE plastic water pipes.
3. Backfill and make good as part of the pipeline runs across Forestry Commission land and we had to comply to their rules & regulations regarding working practices etc.


Application

1. The water is to be used for livestock consumption on the farm next door and for our own consumption at our property. However, until the water meets the organic requirements for human consumption it can only be used for filling toilet cisterns and outside taps for washing vehicles etc.
2. The water has to flow through the pipeline continuously so that it cannot freeze during cold snaps so part of the flow will be directed through the heat exchangers of a secondhand IVT Ground Source Heat Pump.



Logistics and Equipment

1. We have a Kubota KX91-2 and a Volvo EC15B plus one ancient Landrover Defender 110.
2. Two off 100m reels of marine rope with a breaking load of 4 tonnes
3. 100m of vertical height to place 800m or so of pipe.
4. Limited time periods to work in as our property is a holiday let and the neighbour's is a working farm.




The Geology

Thw Water source close up.jpg
Here is the water source around 100m vertically above the point of use. After pipe losses [more on that later] there should be between 2 and 10 bar of pressure available at the taps.



View of water source and trench.jpg
This is a view of the water source as the trench approaches the point where the 2 pipes diverge - one to the farm and the other to our place. This trench was dug by the Kubota KX91-2.


View from Water source.jpg
A view of the same scene but from the water source perspective.



The 800m Trench.jpg
......and again.

[jackpreacher]

All went to plan during March 2012 through to August. In the July Doug was bought and his job was to dig the 300m of trenches on our land.

..all was going well.....albeit a little smokily, and then he died in the trench.


Doug just before he died in August 2012 #2.jpg
This shows my incompetence on a mini-digger.......but what great fun it is.



Doug just before he died in August 2012.jpg
This is almost the spot where Doug died........



Bad memories of the Injection Pump Failure.jpg
I hate this photo...........



I can still remember the tinkling sound the injection pump made as it fell into the sump..........

but that was then, and since February 2013 we have got on with the project and almost completed it


Progress as of April 2013

1. 2 runs of 800m of MDPE pipeline is in=situ and either buried or laid overland.
2. All trenches on the farm and our place have been back-filled and .....ahem.....landscaped.

More photos to follow next week. we have this week coming up to connect the water up, filter it and try it out.
The Heatpump is already plumbed in - see here - and I had it working last week with a temporary connection from the fell supply until the valves all clogged up due to all the crud getting into the pipeline when I was hauling it up the fell.....still, it's all cleared now.

[245dlc]

Jack I'm curious about the intake of your pipeline is there a small dam or weir to help funnel the water into the pipeline? Interesting project nonetheless most water streams in the area around here are either contaminated from agricultural runoff or by animal activity such as beavers (they are largely responsible for spreading the parasite Ghiardia) however we do obtain our drinking water from a very large aquifer in a limestone formation about 200-400 feet underground that is probably close to the same size if not bigger than all of England.

[jackpreacher]

Jack I'm curious about the intake of your pipeline is there a small dam or weir to help funnel the water into the pipeline?

That is the critical part !!
So far I have just put a 4" flexible pipe in the stream and held it place with rocks - but that is just to test the pipe connections and flush the system through. However, this week I'll be installing the intake proper, designed by, ahem...ahem...yours truly but I'm sure it's something someone else has done many times before.....

The actual intake design is not represented here - this is the initial filter/sediment trap and flow regulator designed to keep the pipeline full of water with no air in the system.

How it works:
Water from the intake is fed into the tank via 4" flexible pipe. The reservoir is based on a regular 45 IMP/55 US gallon oil drum.
As the water level rises the float lifts the flap to let water into the pipeline. As the barrel is fully sealed there needs to be an overflow which also acts as the vent. The excess water is fed back up to the intake so effectively making the intake the 'head' of the system. The intake is around 3m vertically and 10m horizontally away from the reservoir which gives a hydraulic pressure of 0.3bar if the reservoir is full. This should just be within the limits of the oil drum, but if not I can position the overflow lower in the stream as that is what will determine the pressure in the reservoir.


Intake Design flowing.jpg

If the inlet water flow rate decreases then water level will drop in the reservoir and the float will sink, effectively choking off the water into the pipeline. There will be a hysteresis effect whereby the flow rate out of the reservoir should balance the flow rate in. This should, in theory, avoid the ingress of air into the pipeline.

Intake Design Closed down.jpg

[jackpreacher]

Constructing the intake reservoir

We managed to get some work in on the Fell supply this week.

The design of the intake reservoir has changed somewhat although the design is very similar. I've used 4, high flow float fillers, inverted. Tests today showed these can handle flow rates of 3 litres/second each so we should be able to get a high flow with around 150 psi.

Incidentally, the temporary intake up the fell has been reliable and our Ground Source Heat Pump has been running off the water for 4 days now. Heating costs have been reduced enormously due to the massive reduction in wood pellets consumed by the pellet boiler.


Pipework in the stables.jpg


Fitting a 90mm flange to an oil drum lid.jpg

Copious application of sealant.jpg

2 intake flanges and the small 25mm overflow-vent pipe.jpg



Oil drum with 3:4 inch float valves fitted.jpg



4 inverted float valve fillers.jpg


Reservoir fitted with 25 and 32mm MDPE pipework.jpg




Outflow 63mm pipe and ball valve.jpg

[jackpreacher]

A great disaster!!

....and it was all going so well.......

Part of the fell supply is diverted off to supply the Heat Pump in the boiler room. Now HP's are the holy grail of heating systems as they 'appear' to create heating out of nothing, but they are very simply fridges run in reverse. So, imagine having a 100 litre bath of water sitting at 12C, then pouring in a kettle full of boiling water, well, after mixing the hot and cold together the bath water will be at 12.5C, or thereabouts [there are equations to figure out the exact temperature...I'm just using arbitrary, 'ballpark' figures].
A heat pump, whether Air source[ASHP] or Ground source [GSHP], manages to extract high grade heat [the boiling water from the kettle] from low grade temperature sources [the bath and kettle water mixed], but a lot of low grade heat must be passed over the heat exchangers in order for this to happen.

In the case of our GSHP, I substituted the water/glycol heat transfer fluid that is designed to be used by a GSHP with a direct flow of fell water through the plate heat exchanger, PHX. The fell water came in at somewhere between 7C & 9C at a flow rate of 12 gallons/minute and left the PHX around 4C lower. It worked fantastically and heated our ]or rather, the bank's ] 8 bedroomed holiday let for the cost of approximately £4.50 per day, which is, believe me, pretty damn good....comparable to what a decent gas combi boiler could achieve [if we could get gas.......which we can't]

Then.......the PHX started to leak the fell water into the refrigerant lineset.....which basically wrote off the whole Heat Pump.
So we ended up with a flooded compressor, filter drier, etc etc. The refrigerant dissolved into the water [luckily it's only R407C which is not a risk to global warming or other environmental issues] so the pressure in the system just vanished.....the compressor became water flooded and began to make terrible noises due to water slugging.


Argh

Not good.


..and all my fault....


Darn' it.

[jackpreacher]

So ....I have to fix it.

To be clear, I can only fix the HP up to a certain point - to recharge the HP with refrigerant has to be [legally] the job for an 'F' registered gas engineer who is trained in handling refrigerant gasses like R407C, R410A and the like. These are the gasses that are heated/cooled by the compressor/evaporator. In the old days, gasses like R22 were notorious for being tricksie to handle and dispose of because of their ability to deplete the ozone layer, so manufacturers devised far better performing and safer refrigerants......mainly non-flammable as well........always a good thing.


PS: The electric lawn tractor is just going to have to wait a bit...............

[jackpreacher]

First up was to drain the central heating water out of the HP. The loop of central heating water is only around 20 litres as the HP links into the CH via a flat plate heat exchanger, similar to the one that FrankieB uses.

The titles of the photos should explain what's going on.

Draining down the Inner Cylinder and water jacket.jpg


Removing the insulation from the compressor.jpg

Prising off the electrics cover.jpg

Noting the wiring loom connections before dismantling.jpg

Hooking up a gauge to the HP line to check the pressure in the refrigerant sid.jpg

Disconnecting the central heating pump, hidden by my hand.jpg

[jackpreacher]

Disconnecting the Ground Loop circulation pump.jpg

Removing central heating pipes from the pump.jpg

De-lagged compressor and HP lines with original owner markings!.jpg

Condensor flat plate heat exchanger.jpg

Removing the capacitor enclosure.jpg

Opening up the capacitor enclosure.jpg

The cracked capacitor.jpg

Shorting out the capacitors in case of residual charge being present.jpg

[jackpreacher]

Removing the REGO unit's earth strap.jpg

The HP pressure switch had to be disconnected.jpg

Disconnecting the ground loop 28mm pipework from the evaporator plate heat exchanger.jpg

LP Shrader, ground loop pump and evaporator connection.jpg

Getting the sensor wires out of the way.jpg

Labelling every single cable.jpg

Disconnecting all the sensors from the REGO control unit.jpg

Pulling the REGO unit away from the chassis of the Heat Pump.jpg

Pulling the ribbon connectors off the REGO 2.jpg

Pulling the ribbon connectors off the REGO.jpg

Removing the sensor input matrix.jpg

pulling the matrix away from the chassis.jpg

The sensor matrix board is clearly labelled with which sensor plugs in where.jpg

[jackpreacher]

Unbolting the 4 nuts which hold the sprung tray which the heat pump is mounted upon.jpg

The heat pump withdrawn from the chassis and mounted on a workbench.jpg

Stripping off the insulation.jpg

The sight glass is off the scale!.jpg

Cutting out the compressor.jpg

After draining the water out of the compressor I filled it with compressor oil to preserve the w.jpg

[Vinpetrol]

Hi Jack
sorry to hear its gone a bit Pete tong
despite your bad luck this all seams fascinating to me. I am amazed you can do so much of this yourself . We have fitted a few heat pumps in our projects but I have never been that deep inside the guts of one.
Do you have an engineering background ?

Best of luck getting it going again

Vin

[jackpreacher]

Hi Jack
sorry to hear its gone a bit Pete tong
despite your bad luck this all seams fascinating to me. I am amazed you can do so much of this yourself . We have fitted a few heat pumps in our projects but I have never been that deep inside the guts of one.
Do you have an engineering background ?

Best of luck getting it going again

Vin

Thanks for the tea and sympathy Vin!.....
I was an engineer a trillion years ago but have forgotten most things since - its fun just figuring stuff out again.....I suppose the laws of physics and chemistry don't really change that much...

As for the heat pump, well, it only has one moving part (compressor) and a fixed amount of refrigerant (1.4kg), although adding the charge is straightforward enough the ambient conditions must be taken into account (temp & humidity). These are all figures from refrigeration data sheets. The pipework must be free of moisture and not leaking......hence the use of a Vacuum pump to evacuate the lineset.

[jackpreacher]

....just had the price for a replacement PHX....

£532.80 inc FAT & delivery

[jackpreacher]