How it works and how to maintain it.


The Borehole


The bore is 70 meters deep and lined with steel to a depth of 50 meters. Water from aquifers peculates through the porous chalk layer and rises up the bore to a depth of 40 meters below the surface. Water refills the bore at a rate of 4 cubic meters per hour, so this is the maximum rate of extraction. If this is exceeded (or if for any other reason the water level drops) the control panel in the pump house will automatically stop the pump to avoid damage.


The pump is a Pedrollo 4SR 4/14 – its specifications are in excess of what we currently require. The pump is guaranteed for 12 months but can last for 5 years (or much longer) depending upon water quality. It can be checked electrically every year to see if the motor is wearing out. It can be cleaned if needed, but the advice I was given was to use it until it breaks and then buy a new one. The pump was installed by Cruwmans.




The Pump House

Pressure Control

The pump house contains the control panel [22] (Instructions) for the submersible bore-pump. The purpose of the panel is to protect the pump by working in conjunction with the pressure sensing switch [3] controlling how/when the pump switches on/off, it also switches off the pump is the bore is dry. It was pre-set by cruwmans so contact them if there are issues with it.

The pressure sensor [3] is currently set to operate at 4-5 bar. It switches off at 5 bar and on when the pressure in the pressure vessel [2] drops by one bar.

The pressure vessel [2] operates as a buffer so the pump does not need to switch on and off as frequently as it would otherwise. A second pressure vessel is [11] under the platform to help smooth out the flow up to the tower. The pressure on the pressure vessels should be checked maintained every 6 months instructions  the pressure with no water in the tanks should be approx 5 bar. (I can’t remember exactly the pressure so check with

if there is a power failure or if the fuse under the platform fails then the readout on the control panel [22] will be blank.


Valves and Feeds:

Valve [7] controls the feed to the land – regardless of whether it is from the tower or direct form the bore and pressure vessel.

Valve [8] controls feed from the tower – make sure this is open if you intend to use water from tower on land. There is a second valve to control feed from tower to the land under the platform [10]

The flow reducer to land [5]  is currently set at 2.5 bar  this could be increased to 3 bar if needed.

The feed from the bore, to the building is closed using valve [12] under the platform.



This is controlled by a plug-in thermostat that is set for heater to come on a 2 degrees. The heater is to protect the switches, sensors and valves from being damaged by freezing conditions There is a battery in the thermostat but if there is a prolonged power cut it might be worth checking. Also check each winter.

NB: The pump house needs improved insulation and a better door. The pipes at the rear are exposed and vulnerable to freezing. Ideally the whole shed should extend to the rear so all of the pipes are protected by the heater.



Under Platform


Under the platform are two filters (particles [13] and iron [14] ) and a second pressure vessel[11]  to maintain pressure for pumping to the tower and flushing the iron filter. The pressure vessel should have 5 bar of pressure when empty. Check every 6 months.

The feed from the tower to the pumphouse (and continuing to the land) can be controlled by valve [10].

The electrical switch [9] contains a 13 amp fuse. This is the power to the pump house.



The coarse filer is to remove and large particles that would reduce the efficiency of the iron filter. The iron filter works by drawing in water and oxidising the dissolved iron (making rust) the rust is then removed from the water because it sticks to the filter media inside the tank [14]. Every third day then large volumes of water are passed though the filter media and physically washing off the rust, which passes down the drain. This process wears away the filter media which might need topping up every 12-36 months.

The coarse particle filter [13] needs cleaning every 3-6 months. Simply unscrew to remove a stainless steel filter and rinse it under a tap. To clean close [12], drain pressure vessel [11] (by flushing or by running taps)

The iron filter [14] requires servicing every 12-36 months by initially service after 12 months and then the engineer will suggest a frequency. The clock on the iron filter head should read the correct time. Set it by using the up/down arrows. The other button is for manually flushing (pumping lots of water quickly through the iron filter and out to the drain via [16]. The iron filter is set to “flush” at 2.00am every third day.

The meter on [14] should read approx 3 bar when resting, 1.5 bar when pumping.




Bell Tower

The bell tower contains a fine particle filter to ensure that only clear water passes through the UV filter, so that nothing interferes with the UV light shining through the water.


The fine particle filter [18] contains a disposable filter that needs annual replacement.

The UV steriliser [19] (sterilight sp-950, Instructions ) has a control box that measures the transmittance of light and tells you when the bulb needs replacing. Press the green, lit button once to see the transmittance. This is acceptable if it is above 55% but when it falls below 65% then the quartz sleeve will need removing and cleaning. NB. shut valves before removing the quartz sleeve. Pressing the button a second time will tell you how long before the bulb needs replacing. An audible alarm will sound when the bulb needs to be replaced. The alarm can be silenced for 7 days to allow time to order a replacement (see instructions). The bulb can be slid out BEHIND the green/red pipes.






If the flow to the tower is too weak,

  1. Check pump house pressure gauges, if they are too low then check pressure in pressure vessel[2]
  2. if everything OK in pump house, check pressure in pressure vessel under the platform
  3. Check pressure on the iron filter [14] should read 3 when resting, 1.5 – 2 when pumping. If resting pressure is low then clean particle filter [13]. If pumping pressure is too high check float valve in tower tank.
  4. If still not working then call



If the water pressure is too low out of the taps

  1. Check/replace disposable filter in tower [18]




To use water from tower on Land

I there is a power failure then no water will pump up to the tower or out to the land. There is sufficient water i the tower to last for several hours (depending upon demand) but with no power the land water will stop almost immediately.

To switch the land water to feed from the tower open switches [8] in the pump house and [10] in the cellar. [7] should already be open. To return to bore-feed to the land, close [8] and [10]




To return the whole system to mains water:

1. Switch land water over to the tower

2. Open valve [21] in carrol corridor

3. Close blue valve at bottom of tower, outside chapter room.

4. Switch off any other pumps/filters as needed.



Every 3 months

Clean Particle Filter under platform [13] (if clean then frequency can be reduced to every 6 months)



Every Six months

Check pressure in both pressure vessels

Clean Particle Filter under platform [13]

Check Clock on iron filter [14]

Check all pressures on all gauges



Every Winter

Check thermostat, heater and insulation in pump house.



Every Year

Check pressure in both pressure vessels

Cleans Particle Filter under platform [13]

In tower, replace UV bulb [19] and particle filter [18]

Check transmittance on UV filter [19]

Arrange for servicing of Iron Filter [14]

Electrical test pump (if you can be bothered)





 Cruwmans: for borehole, pump and control panel

Mbl – 07880 778406 or 07989 787079
E-mail –
Unit 5f, Clockhouse Farm Ind. Est.
Cavendish Lane
CO10 7PZ

Pumps and Filtration: for all filters

Office: 01473 831261

UV Sterilizer parts and repair: