Attaching a Copper Pipe to a Lead Pipe Supply

Although the use of lead for new plumbing purposes has long been prohibited, it is not uncommon to find it still installed in older properties. Most homes built before the 1950’s depended on either iron or lead pipe-work for their water supply.

As new plumbing materials were developed for transporting water and gas supplies, most accessible lead plumbing was removed from buildings as part of a normal upgrading of supply networks. In domestic properties, the need to facilitate water supplies to new appliances took advantage of the versatility of copper. Copper pipes were easy to work with and could be cut and joined to accommodate any requirement.

Lately, plastics have started to replace copper as a lightweight and durable alternative. Water supply companies have utilised plastic pipes on a grand scale to upgrade their deteriorating and previously poorly maintained supply networks.

However, it is not uncommon to still find some older domestic properties still supplied with potable water from a lead rising main. Lead pipes are usually conspicuous by their dull, grey colour. When the soft, grey surface is scraped away, the shining, silvery material that is exposed will provide confirmation.

Wherever possible, these old lead rising mains should be removed and replaced with a suitable alternative material. A lead rising main may still be present in an older building for a variety of reasons. It might simply have been overlooked.

Not surprisingly, the most common reason for leaving a lead rising main, and the rest of the lead pipework supplying it, in place is the cost of replacing it. The cost of removing and replacing old lead pipes back to the boundary of the property must be met by the property owner. In many cases, this considerable cost provides a disincentive.

How much of a health risk is perpetuated by leaving a lead main in place is a matter of conjecture. Undisturbed lead pipes can develop an interior coating of mineral deposits that inhibit the transfer of lead into the potable water supply.

Where a homeowner has concerns about a possible health hazard from existing lead pipework, water testing will indicate whether lead is a problem.

Perhaps one of the most common problems to occur with an existing lead rising main is leakage around an old copper to lead union. In the past, internal lead pipe-work was removed and copper was joined to the remaining lead main using a soldering technique called ‘wiping’.

A wiped joint was created by stretching the cut end of the remaining lead mains and inserting a length of clean and fluxed copper pipe into the widened and cleaned neck. Widening the neck also produced a cupped shape, which had a practical purpose. Firstly, a suitable length of metal rod was inserted into the top of the copper pipe and extending into the lead pipe to prevent movement between the two pipes. Then, bar solder was melted with a blowtorch and allowed to fill the cup on the lead pipe neck. This formed a union between the two pipes. The solder was gradually built up by periodically wiping the molten material with moleskin, or other suitable cloth to form something resembling a thick bandage. Part of the skill was to complete this task without melting the lead.

Although this procedure was prohibited by the Water Regulations some years ago, it is still regarded as a true plumber’s skill and is sometimes used as a temporary measure to repair leaking unions.

Over time, these previously wiped joints are susceptible to corrosion. This is often caused by the electro-potentially dissimilar properties of copper and lead. The corrosion eventually causes leaks in the wiped union that need to be repaired.

To repair on old copper to lead union, or to install a copper ‘T’ component into a lead pipe, a brass coupling called a lead-lock or other similar brass or plastic compression fittings are now the only couplings permitted for joining onto lead.

With the mains water turned off, the old wiped joint can be removed with a hacksaw, or the lead pipe cut at a suitable position to accommodate the lead- locks.

A lead-lock compression fitting works by creating a tight seal onto the lead pipe by utilising an internal gripper and friction ring to compress a large rubber ‘O’ ring against the surface of the lead pipe. This forms a watertight seal. The lead-lock fitting is made of brass, and so eliminates the problems associated with connecting dissimilar metals. The opposite end of the lead-lock has normal compression fittings to accommodate conventional copper or plastic pipework. Other permitted joining components use a similar technique.

Where possible, a small cut-off section of the lead pipe should be taken to the plumber’s merchants to ensure that the correctly sized lead-lock is obtained. Old lead pipes were manufactured in different gauges and were usually categorised by weight. Each different weight corresponded with a particular diameter.

Where it is not possible to remove a section of lead pipe for comparison, possibly because the remaining lead pipe is too small, a length of cotton can be wrapped around the lead pipe, and where one end joins another, the cotton can be cut. This piece of cotton, when measured, will provide the circumference, which when divided by 3.142 will establish the lead pipe diameter.

Nevertheless, when trying to fit a suitable lead-lock, it may be necessary to file away any external grooves or raised surfaces on the lead pipe to ensure a snug-fitting ‘O’ ring and water-tight connection.

It is also very important to prevent the soft lead pipe from kinking, bending twisting or deforming when applying tension to lead-lock couplings during tightening. A suitable set of grips applying an opposite force will prevent this problem occurring.

When completing the join, the mains water should be turned on gradually and the new connection closely monitored for signs of leakage. Where a leak is detected, the lead pipe can be filed to modify it and the fitting replaced or sometimes adjusted and re-fitted.

Unfortunately, a lead rising main is often located in the most inaccessible of places and working on it requires considerable patience and manual dexterity. If this is the case, it is often more appropriate to employ the services of a qualified plumber to undertake any connections to a lead main. Where a subsequent joint failure occurs due to an incompetently installed fitting, insurance cover for water damage may be affected.

After disturbing any existing lead plumbing, it is a wise precaution to run the cold-water tap for ten minutes or so to flush through any minute lead fragments that may have become dislodged. It is also good practice to run cold water through a lead supplied drinking water outlet for a few minutes prior to using, particularly if the water tap has not been operated for a day or more.

Although no longer used for installations, old lead pipe-work can continue to provide safe water for domestic consumption. However, where possible, old lead pipes should be removed.

Remote Diagnostic Boilers

Imagine getting a phone call from your gas supplier informing you that your boiler has been talking to them.

Your boiler has advised them that although it is working satisfactorily at the moment, it is, nonetheless, in imminent danger of a catastrophic breakdown. Consequently, they need to send their engineer around to replace a part. The boiler has informed them which part it requires and they just need to arrange a convenient time to pop round and fit it.

Now. Does that increase your comfort level, or reduce it?

Of course, the self-diagnostic capability of appliances and machinery is nothing new. You probably encounter it when you take your car for a service and the garage simply connects your vehicle to a laptop computer. From this, they can detect most faults and also ensure that the mechanics and electrics are all running efficiently.

If you have a modern, top of the range domestic gas boiler you may well have seen a gas engineer carrying out a similar process.

The boiler’s ability to interact with technology is nothing new. Boilers, sensors, programmers and timers have all been interacting together in the home for many years. The practice of remotely communicating with the domestic boiler has already become well established. A growing number of householders are controlling their heating via smartphone and android gadgets. These devices utilise broadband technology to monitor and adjust boiler function and household temperature settings from almost anywhere in the world. Not surprisingly, adjustments to the householder’s heating controls are now often made from an armchair in the home and sent over a few thousand miles of networks and satellite connections to a receiver a few feet away.

But this next step forward in communication with a remote central monitoring facility, which can be hundreds of miles away, is already past the development stage and being trialled by one major energy supplier.

Remote Appliance Diagnostics Systems or RADS for short are being heralded as the next great innovation to revolutionise boiler operation for householders. Offering a sophisticated electronic control and monitoring service through a remote diagnostics centre, it is claimed that these devices will maximise comfort and efficiency for boiler owners.

There is no doubt that the early identification of impending boiler problems will provide an extra level of confidence for households, particularly during the winter months. Nobody welcomes an unexpected boiler breakdown in the middle of winter.

There are other benefits too. Most boiler owners are familiar with the situation where an engineer has been called out to investigate the cause of a malfunctioning boiler. The diagnosis usually requires a considerable amount of time fiddling with the boiler’s internal components and a certain amount of head scratching. Inevitably, the engineer comes to a conclusion which usually centres on the recommendation of the fitting a new part. Fitting the part is a straightforward procedure. Ordering and getting the part is another matter.

With RADS, a remote diagnosis should ensure that the engineer arrives pre-supplied with the necessary components.

Through a RADS system, the boiler will be in what is referred to as ‘real-time’ contact with the remote monitoring centre. Real-time is one of those phrases that sound high-tech, but simply means connected to and maintaining a regular contact with the centre. This ensures that the boiler’s operational performance can be monitored for unusual working behaviour patterns. This monitoring will eventually produce a boiler behaviour history, which, when combined with information from maintenance and repair history, will provide valuable information for analytics and engineers.

When an actual or potential malfunction is detected by the provider’s monitoring centre, the centre alerts an engineer. Remotely, the provider’s engineer can use diagnostics software and analysis to determine the possible cause of the problem. In doing so, he can pre-source and obtain any necessary parts from the energy provider’s stores.

Meanwhile, the energy provider’s monitoring centre contacts the boiler owner to arrange a convenient time for the engineer to call. This means that the provider’s engineer can attend to the boiler at a pre-determined time, carry out a few checks to confirm the fault, and immediately install any necessary parts. This, of course, can save considerable cost and inconvenience for the householder and also improve the efficiency of the provider’s engineering department.

Many boiler manufacturers are now building boilers with this technology pre-installed in anticipation of an eventual general consumer uptake of the system. Other companies are investing in developments to provide the necessary components to allow existing boilers to be modified to function with RADS.

Along with remotely controlled and monitored smart meters, boiler-monitoring looks likely to become a normal part of an energy supplier’s service.

How far these developments will provide other additional benefits to consumers remains to be seen.

Having remote boiler diagnostics may remove the potential for intervention by the homeowner. The service provided by the energy provider will ensure that the provider’s engineers facilitate repairs and maintenance to their customer’s boilers. This will allow them to monopolise the boiler repair and maintenance trade, with the potential to affect the businesses of many small, independent boiler heating and plumbing specialists.

Along with smart meters, it could also provide a disincentive to energy customers to source competitively priced alternative energy sources and to easily switch between suppliers.

Perhaps the greatest and growing concern for homeowners is the increasing monitoring of their activity by monolithic companies who have become obsessed with collecting and analysing data connected with consumers and their behaviours. This information is often used to influence and change behaviour patterns in a manner that is beneficial to the companies who collect it, or to those who sell it on to other interested parties.

New energy heating and control technology undoubtedly brings many benefits to homeowners and their families, but when the control of that technology is removed from the homeowner, a certain amount of discomfort about the issues surrounding remotely controlled systems will have to be overcome before they are totally accepted without suspicion

Renewables and Intermittency

Energy surrounds us. Light and movement combine in a dynamic process of transforming energy from one form to another. Perhaps, like me, you can remember school physics teachers remarking that ‘energy cannot be created or destroyed; it just passes from one form to another’.

So, what is the problem with current fuel supplies?

Simple. Because of our increasing demand for energy and our over reliance on what might be still considered cheap fossil fuels, we are coming close to exhausting fossil fuel reserves altogether. We take electricity and natural gas for granted. As a minor example of a more serious and complex situation, our toys and gadgets like computers and mobile devices use little power individually. However, on a global scale, it takes the combined fuel output of several fossil fuel burning powers stations just to power the servers that supply the World Wide Web, which these devices rely on. Moreover, that does not include the power used to run the devices, the power used to create the devices and the power required to extract and purify the materials used in the devices’ construction.

Of course, fossil fuels are renewable. The problem is that they take millions of years to form and unfortunately, we cannot sit back and wait.

Nuclear fuel was once heralded as the saviour for human energy requirements, however, such salvation has not only became a nightmare regarding the security issues surrounding the storage of spent fuel, the cost of building and the short life and subsequent de-commissioning costs of nuclear power stations makes the electricity they produce very expensive indeed.

Tapping into other energy sources around us is really quite simple. However, the cost of doing so can be a disincentive without government funding.

Renewable energy sources can be divided into two categories. Intermittent supplies, such as wind, wave and solar.

Non-intermittent supplies like energy crops and biomass, methane digesters, hydroelectric and tidal barrages.

Although all of these have some characteristics that can make them either difficult or unethical for considering as large-scale energy converting systems, the intermittent types pose the greatest challenge.

Intermittent energy sources are, as their name suggests, unreliable or perhaps more appropriately, unpredictable in their output. They are what is termed ‘The Achilles’’ Heel’ of renewable energy supplies.

As such currently they can only be used viably as an addition to the energy demand as electricity supplementing the National Grid.

In looking at conventional UK human activity and power requirements, it can be seen that demand for power is lowest between 11.00 pm and 6.00 am. Energy demand increases slowly during the day and then reaches a peak between 6.00 pm and 8.00 pm. Being able to respond immediately to peaks and demands, particularly those that are unpredictable like supplying increased energy during a cold spell of weather, requires a responsive power source. Intermittent supplies cannot be turned on and off when the source of the supply is not available.

What is needed is a way of distributing renewable energy from intermittent sources in a way that can reduce or remove the intermittency factor.

Prophetic visions abound about possibilities such as global intermittent energy collection devices with energy transported around the globe as electricity on a global grid network. Daylight supplying night time areas and vice-versa with increased nigh time wind supplies. DC current replacing the problematic nature of transporting AC current over large distances. Huge global energy ‘granaries’ of harvested energy stored in batteries or as vast underground caverns of compressed air operating power station generators during peak energy demands.

In reality, and away from imaginations that are perhaps too futuristic for present immediacy, the solution to renewable energy intermittency is probably already well under development.

Energy obtained from intermittent sources can be easily and efficiently converted into hydrogen and stored under pressure as a liquid.

Hydrogen is a very clean fuel, simply converting back into oxygen and water when it is burned to release its energy.

Transporting energy as a liquid or a gas along pipe networks is a highly efficient method of moving energy across distances. There is little loss of energy, unlike the horrendous losses on electrical grid supplies.

What is more, experiments in America have concluded that mixing small amounts of hydrogen gas in with the methane gas supplying domestic and industrial usage causes no problems with appliance operation. Eventually, all appliances could be converted to run on hydrogen, even vehicles.

Surely, gas from wind power has to be the most feasible means of dealing with renewable energy intermittency. Producing hydrogen gas and circulating it through established gas networks supplying domestic users, industry and local electrical power generating stations, must be an attractive solution.

Although the exploration and extraction of shale gas may go towards supplementing and securing gas supplies in the UK, any further developments in storing intermittent renewable energy production will very likely continue to progress along hydrogen production and storage techniques to continue the UK’s utilisation of gases as a fuel source.

 

Replacing a Damaged Central Heating Pump

Heat pumps are the workhorses of wet central heating systems. Generally hidden from sight they quietly operate, pumping the central heating fluids around the radiators at the thermostats command. Naturally, like all mechanical appliances, they will eventually fail beyond economic repair and need replacing.

Usually the failure of a central heating pump is diagnosed after discovering that the house has become cold or that the boiler refuses to fire-up. Sometimes the clue to a pump failure will be the symptom of hot radiators upstairs and cool ones downstairs. Further investigations, such as checking for the free rotation of the pump and ensuring the presence of a live electrical supply will usually confirm the diagnosis.

Whatever the cause, there are two methods of sorting out the problem. Either call for the services of a heating engineer or change the pump yourself.

Because the removal and replacement of a wet central heating pump is usually a relatively straightforward task there is no reason why a confident householder with basic DIY skills should not undertake this procedure themselves. However, if changing the pump starts to become arduous and problematic because of restricted access or seized isolating components, the work should be transferred to a skilled engineer. Although this will be an expensive option, it could work out cheaper than paying to rectify a bodged DIY attempt.

Before proceeding to change the pump, it is always a good idea to source a replacement. An identical pump is preferable if the existing pump was capable of performing its task without effort. Never be afraid to ask for advice from the retail outlet, it is free. One of the benefits of fitting an identical pump is that it will fit straight into the exact position and the fitting area of its predecessor without the need for modification of the existing pipe-work.

Where an identical pump cannot be sourced, pumps manufactured by competitors will do the job. It will save considerable time and effort if the new pump will fit exactly into the gap between the original connection pipes.

Having sourced and acquired the new pump, examine the old pump in its current position. Hopefully it will have valves either side of its fitting point to enable the pump to be isolated from the central heating circuit prior to removal. The valves may be gate valve type or discreet pipe valves that are usually located on the union joints. Often, because of infrequent operation, these valves may require a little gentle persuasion to make them operate and close effectively. Union joint valves are usually operated with a screwdriver. This type of valve is closed when the screw head is in the vertical position.

Where no isolation valves have been fitted or the valves have become seized, there may be no alternative other than to drain down the entire system.

Having isolated the pump from the central heating circuit the next task should be to disconnect the pump motor from the electrical supply. It is imperative to ensure that the electrical supply to the pump has been turned off prior to removing the pumps electrical housing cover. The boiler and all its electrical components such as timers and programmers should be turned off and to make absolutely sure that the electrical supply to the pump has been removed, turning off the entire domestic electrical supply should be considered. That might sound extreme, but for DIY purposes, there are no concessions when it comes to making fatal mistakes.

Having ensured that there is no electrical supply to the pump, the electrical housing cover can be removed and the wires disconnected from the unit.

It is important to determine the direction of flow through the pump and pipe-work. This will usually be indicated by an arrow moulded into the metal casing of the pump. It is important to ensure that the new pump, when fitted, pumps the circulatory fluids in the same direction.

The pump union joint nuts on the pipe-work at either side can now be undone to remove the old pump. It is advisable to place a bowl or suitable receptacle to catch any water that may exit as the pump is removed.

Occasionally, the union joint nuts become stubborn to turn. They can be persuaded to turn by giving them a sharp tap with a chisel and hammer. The angle of the chisel on the nut should direct the force in the correct direction to ensure that the nut is loosened and not tightened further. Once freed, the nuts can be unscrewed and the old pump removed and discarded.

Once the pump has been removed, any washers or debris in the remaining pipe unions must be cleaned out and completely removed.

It is perhaps easiest to connect the new pump to the electrical circuit prior to plumbing it into the heating circuit.

Ensuring that that the arrows on the new pump indicate that the direction of flow of central heating fluid is identical to the previous pump, the new pump can be plumbed into the circuit in accordance with the manufacturers instructions. The application of a bit of silicone grease to the screw threads on the pump connections will help to seal the union and make any later replacement much easier.

When the new pump has been installed, the isolation valves can be opened and the electrical supply re-instated. The boiler and all relevant timers and programmers can be turned back on and the pump should operate. It will probably require bleeding to remove any air trapped in the new pump. This is accomplished by locating the bleed screw on top of the new pump and loosening it to allow any trapped air to escape.

Where the system has had to be drained, it should be re-filled, not forgetting to add inhibitor prior to re-starting the heating system.

As with any new plumbing work, it is always a good idea to inspect the work area frequently for any signs of water leaking from joints or the newly installed appliances.

If all has gone well and the DIY task has been completed successfully, the pump should operate perfectly and provide good service for many years.

zoning

The concept of zoning might seem a little complex but in all probability, if your system is a conventional indirect hot water system, you probably have a simple example of a type of zoning in operation. Hot water generated by your boiler is directed to either the domestic hot water cylinder, zone one, or the central heating, zone two. In this case, a motorised diverter valve maintains the zones.

The purpose of zoning is to optimise the domestic heating system to ensure that the different areas within the house are heated only to the required level, which in certain parts might be quite infrequently or even not at all.

In a home where a single thermostat operates to control the entire heating system, the whole house will be heated to the setting on the thermostat regardless of whether all the rooms are occupied or not, or whether they are receiving supplementary heat from sunlight or cooking tasks. The thermostat will take its base setting from its location.

Many thermostats are inadvertently placed in unsuitable positions, for example in a cold hallway or a draught, and often set to achieve an almost impossibly high temperature. This can mean that no matter how hard the boiler works, it can never reach the cut off point.

In this situation, the boiler runs continuously with some rooms cool and others uncomfortably hot.

Changes to the Buildings Regulations have been introduced to reflect the importance of conserving energy by creating zones to maximise boiler efficiency. In new builds and complete installations, the directions are mandatory and in boiler replacement situations, the directions are related to good practice.

Consequently, any new system in a home that is not based on an open plan format must have at least two heating zones. These must be individually controlled by the operation of a thermostat and a zone valve. Radiators must have Thermostatic Radiator Valves (TRV’s) fitted except those in rooms with a room thermostat installed and radiators and towel rails in bathrooms.

When replacing a boiler in an existing system it is now good practice to install TRV’s on all radiators, except those in rooms with a room thermostat and those in a bathroom. These should be installed whilst the system is drained down.

Although the generalised instructions in the Buildings Regulations will provide a good basic system of zoning, it is in a homeowner’s interest to plan and develop a zoning system that reflects the requirements of the house occupants.

Installing a timer in a two-zone system can control when heat is delivered to a particular zone independently of the zone thermostats. An example would be a timer, which responds to the expected household activity in the living or cooking areas of the property during the day and then redirects heat to the bedroom zone area at night.

Rather than settling for a simple two zone system, usually zone one, ground floor, and zone two second and subsequent floors, a multi zone system can be constructed to take into account the life-styles and commitments of various members of the household.

By installing motorised diverter valves, each operated by an individual thermostat and timer, zoning can be fine-tuned to allow each zone, possibly as individual rooms, to be controlled with precision. The motorised diverter valves will open and close to provide heat only when it is required. Consequently, the boiler will operate only as needed and in a controlled and efficient manner.

Motorised diverter valves can be fitted with wireless controls and can be operated and programmed along with their individual thermostats and timers from a central control programmer.

For a complete and remotely controlled system of zone and room control, TRV’s are relatively good at regulating individual radiators. They are also ideal for regulating temperatures in different areas, for example a cooler bedroom for sleeping in and a warm living area for relaxing in.

New wireless controlled examples can be remotely controlled from a central programmer, or by a remote control system.  Honeywell Evo Home has a system that can accommodate the remote control of up to twelve wireless TRV’s through its dedicated software system and hardware. A broadband connection is required.

A system called Heat Genius works in a similar fashion to Honeywell Evo Home, but has the extra option of fitting motion sensors in individual rooms and areas. This allows the system to learn about the habits of the house occupants and predict energy requirements based on this learning.

The system also has adequate provision for build and add on technology as and when it becomes available. Installing a complete Heat Genius package in an average three-bedroom property with seven radiators would cost around £800 including the individual room sensors, the TRVs and the Heat Genius Hub.

The efficiencies and controls afforded by installing the components necessary to produce effective zoning are only part of the practical tasks associated with energy saving. Much of the efficiencies these systems deliver are dependent on the energy usage and awareness of the house occupants. Without a concerted effort to minimise heat loss, use energy with efficiency in mind and learn from the limitations of the installed systems, installing technology without interacting with it is a futile waste of time and money.

Where technology and adaptable human behaviour co-operate, major savings in energy and costs can be readily achieved.

The Causes of Low Water Pressure

For some people low water pressure or a loss of the mains water completely, can be nothing more than a temporary inconvenience, particularly if it results from a water service provider’s routine maintenance on the mains supply network.

If this is the case, then the householder may have been fortunate enough to receive the courtesy of advanced notification from the provider. On the other hand, a sudden interruption to supply might be the result of a burst water pipe or other unpredictable system failure, hopefully before leaving the mains and the responsibility of the water provider.

Low water pressure issues that cannot be attributed to the fault of the provider can be caused by numerous problems.

Low pressure can sometimes be an issue where neighbours share a supply pipe from the mains. In these cases, pressure may seem to fluctuate particularly at regular times throughout the day. Increased demand on the water supply will reduce available pressure and this can often be observed in summer when other residents reduce pressure in the supply pipe by watering their gardens.

When a water provider has determined that the pressure at the mains boundary is sufficient, the capacity or internal diameter of the supply pipe may be a problem.

Where a pressure or a flow and capacity issue arises on a shared supply pipe, the owners of the properties that the pipe supplies are jointly responsible for the pipe’s maintenance.

When investigating water pressure issues within the home, a first consideration should be the extent or limitation of the problem. The problem may be restricted to an individual appliance or to an entire system’s function.

A water filter on the inlet valve of a boiler may be blocked and could need cleaning and likewise, a slow running tap may have the same problem on the outlet filter, if one is installed.

Shower-heads can become blocked with lime-scale, seriously impeding flow or preventing operation altogether. These may simply require cleaning or replacement.

Where there appears to be a drop in water pressure throughout the entire domestic water supply of a property, a leak in the pipe-work may be the cause of the problem. Apart from the obvious visual evidence of leaking pipes inside the home, leaks can occur both internally and externally that might not be quite so conspicuous.

If you are fortunate to have a water meter installed it can be worth turning off all the water utilising appliances and taps and taking a reading from the meter. If, after a few hours with no domestic water consumption, a further reading of the meter shows an increased unit usage, then a leak in the domestic system could be the problem. Externally, a leak in the pipe-work below ground will usually show up as a wet patch, particularly on a dry day.

Sometimes a leak in a pipe will be heard and identified by the hissing sound of escaping water under pressure.

Over time, pipe-work supplying the water from the mains can become restricted or completely blocked by accumulated deposits. This is a particular problem with old galvanised pipe-work. Replacing this pipe-work with copper is the best solution.

In some old properties, lead pipe-work may still be installed. This can be identified by gently scratching the exposed pipe. The resulting scratch mark will be silver in colour. Lead pipe-work is quite soft and susceptible to accidental crushing and bending which can restrict the flow rate and pressure within the damaged pipe.

At the point where a water meter is installed, or where the water supply enters the property it usual to find a stop valve. Sometimes, particularly after plumbing has occurred within the property, this valve is turned off and then on completion of the work, is not turned back on fully.

Occasionally, and particularly following provider maintenance work, air and debris can accumulate behind this valve and restrict or prevent flow. Turning on a tap within the property and then turning the stop valve on and off a few times should resolve the problem. If an airlock has been a problem, the water will splutter out of the tap and then normal water pressure should be restored.

In some cases, and particularly where a new occupant has moved into a property, those occupants may be aware of a water pressure difference between their old and the new property. A reduction in water pressure is likely to be noticed where the new property is on a hill or where a supply pipe facilitates the water requirements of numerous homes.

Many new appliances require a minimum operational water pressures and a householder is well advised to ensure that the water supply to the property is capable of meeting the appliance’s requirements. Some appliances will fail to operate without a minimum pressure for safety reasons, for example shower units and boilers.

Water service providers aim to supply a water pressure of 1 bar at the mains boundary. If for some reason the home-owner is unable to meet the minimum pressure required by appliances, the installation of an accumulator water tank may provide a solution. These cylinders store a supply of water imparting and maintaining a suitable pressure which can supply appliances where low-pressure issues would otherwise prevent operation.

It is worth noting that where regular intermittent low-pressure issues occur which are caused by a water provider’s inability to maintain a regular minimum water pressure above 0.7 bar, the home-owner may be entitled to compensation.

Where a provider affects a householder’s mains supply by delivering a low water pressure below 0.7 bar, and lasting for over one hour on two or more occasions within 28 days of each other, the householder may be able to claim compensation from their provider. However, planned maintenance and emergency work on the mains network are excluded from this provision.

 

Micro-bore Pipes for Central Heating Systems

Back in the 1970’s, micro-bore pipes were the revolutionary plumbing material for central heating systems. Copper pipe of between 8 mm and 10 mm was available on rolls and flexible enough to be gently bent by hand without the need for joints and soldering. New developments in manufacturing processes meant that micro-bore plastic pipes were now available that were durable and resilient enough to cope with high temperatures and pressure.

The simplicity of installation meant that installing the pipe-work for a central heating system could be regarded as a DIY task and the home owner could save a small fortune by not hiring a plumber. Professional installations could also be completed in a fraction of the time and at a considerably lower cost. Floorboards no longer needed to be lifted or notches cut into joists to accommodate pipe-work and the work was accomplished quickly avoiding all the previous domestic upheaval.

However, the systems were often incompetently plumbed, sometimes with little regard for boiler output capabilities or radiator output ratings. Micro-bore copper pipes were often kinked instead of being carefully manipulated to achieve curves. Consequently problems occurred which tended to tarnish micro-bore systems.

Keen to jump on the bandwagon of condemnation were the old school plumbers. 15 mm and above diameter copper tubing had long been associated with artisan plumbing practices. The skills that were a feature of the tradesman’s craft were being undermined by the simplicity and flexibility of small-bore copper and plastic pipes. As such, plumbing with such materials was often seen as inferior and cheap.

Never the less, many original micro-bore installations are still operating very effectively today and their owners swear by them for reliability and absence of any, or only minimal maintenance requirements.

The recent economic situation coupled with a growing awareness of environmental issues has seen a renewed interest in micro-bore pipe-work. The cost of copper has soared, along with the cost of other metals on the global market and as a result, entirely copper installations are expensive projects to undertake. The time required to install most copper heating networks is considerable. Time spent cutting and bending material and soldering, brazing or fitting compression joints adds to the cost installations. Not surprisingly, installers are looking at ways to reduce cost and remain competitive.

Micro-bore systems can be used for open or pressurised central heating systems that use a two-pipe flow and return convention.

Micro-bore heating systems can utilise the fact that very little water needs to be present in the system compared with conventional pipe-work. As a result, less boiler heat is required to heat the volume of circulating fluid and a smaller capacity boiler can be installed. The important considerations to observe are the distance of the radiators from the manifold and the output ratings of each radiator.

The pipe-work from the boiler to the manifold is generally 22 mm. Although it is better to place the manifold near to the boiler to save on 22 mm pipe, it is not imperative to do so. Either 8 mm or 10 mm pipe can run from the manifold to each radiator as a flow and a return, depending on requirements.

The length of pipe-work to each radiator from the manifold should be kept below 5 metres. Each radiator must be correctly balanced to provide an 11 degree C drop over its surface from the inlet to the return pipe. Some radiators may incorporate a double valve to accommodate both inlet and return feeds, which also economises on pipe-work.

It is general practice with micro-bore systems to run plastic pipe-work, usually Hep20, below the flooring and then revert to copper where the pipe becomes visibly attached to the radiator. Not only is this more aesthetically pleasing, it also acts to provide more durable pipe-work where unprotected exposure could lead to damage by children’s toys or by other knocks and bumps.

Because micro-bore pipes have less surface area, heat loss from the pipes is reduced. Avoiding joints, which might otherwise impede the smooth flow of central heating fluid, by gently curving the pipes improves flow rates of circulating fluids, but the system pump must be capable of supplying adequate force to compensate for the narrow diameter of the micro-bore pipes. The velocity of the pumped water must remain above 0.3 metres/second.

Because of their diameter, micro-bore central heating installations do require a little more consideration. Although there is no direct evidence to suggest that they are any more prone to blockages than conventional systems, it is advisable to maintain good system management and maintenance procedures.

Rather than advisory or good practice, the use of a suitable inhibitor is a must, as is regular system flushing. Flushing should be undertaken by a qualified and competent engineer who is accustomed to working on micro-bore systems. In hard water areas, the use of a water softener will guard against lime-scale formation, which if anything is more of a problem in micro-bore pipes.

Contrary to some advice, it is not advisable to bury micro-bore pipes for central heating systems within plaster or below concrete screeds. Although micro-bore pipes are used for under-floor heating, the temperature of water destined for central heating is considerably greater. Expansion of buried hot central heating water pipes will cause concrete or plaster to crack.

Micro-bore heating systems do require a little more consideration during the planning stages to ensure all operating requirements are met, but once installed there is no reason why the system should give any less performance or working life expectancy over conventional systems. On the contrary, a micro-bore system actually removes some of the problems that seem to blight larger bore installations.