Common Boiler and Heating System Installation Faults

27 Apr. 2019

Written by Neil Marsh MCIPHE RP RHP EngTech

You may think you are getting a bargain when a heating company quotes a low price for a boiler replacement, however, more often than not, you will get what you pay for …

Boiler replacements are not a cheap process, by using a budget solution it is likely that important aspects of the installation are not being done and that will often lead to further costs to pay at a later date correcting the faults that have occurred from aspects not being done correctly or at all.

FORTHRIGHT have been installing boilers for a long time, and we can assure homeowners with confidence, that doing something correctly takes time and the use of correct equipment! There are very few occasions where a boiler can be installed correctly in just one day. Companies that are installing boilers regularly at these speeds only care about one thing, profit. Companies and installers can often make higher profits by doing so.

Repair work will be more frequent when installation faults are present. They may not show initially and take time to become evident, however, when they do homeowners will be faced with costs to rectify these issues. Manufactures warranties come with terms and conditions that exclude faults due to installation. It is likely that the 3-10 year warranties that most manufacturers are offering nowadays will be invalidated where boilers are not being installed correctly.  Below  are the common installation faults that FORTHRIGHT encounters:

1. Undersized gas pipework

A boiler requires a sufficient amount of gas to work correctly. Faults can occur when the gas supply to a boiler is inadequate. It can even be dangerous in severe cases. 

As gas is delivered into a property at a fixed pressure after the gas meters regulator, the longer the length of pipes and the more bends and fittings used routing the pipework within the property, the more resistance and therefore the less gas will be available at the outlet. Gas pipework needs to be carefully sized and routed to meet set requirements and ensure that it does not compromise with the structure of the building, such as excessive drilling/notching of joists. 

Depending on the distance from the meter, boilers and other appliances with a higher kilowatt input are likely to require larger diameter pipework to ensure the correct supply of gas to each of the appliances.  Larger pipes are more costly and difficult to route, plus many gas engineers do not know or do not bother to size gas pipes correctly. When 28mm and 35mm copper pipework are used, it can quickly add a noticeable amount to the cost of a job and can present issues with routing, as its diameter is often too large to notch into joists without causing defects with the structure of the building.

2. Condensate pipes at risk of freezing

A condensing boiler (all modern boilers) regularly produce condensate which should be discharged to a drain via a condensate pipe. Where condensate pipes are installed externally, and freezing conditions are present, the condensate within the pipe will begin to freeze as it makes its way to the drain. With enough time the condensate pipe will freeze and prevent condensate from escaping to the drain, which will cause the boiler to stop working. The larger a condensate pipes diameter and the more it is insulated from the freezing air surrounding it, the longer the duration before freezing takes place. The UK has suffered some harsh winters over the last number of years where temperatures have been well into the minuses for several days or weeks at a time. When weather like this occurs, condensing boilers are at high risk from failure, and the boilers that have poorly installed condensate pipes will fail first.

Inevitably condensate pipework freezing can only be prevented to a point. We have witnessed entire soil pipes and drains freeze solid in extreme conditions, which would eventually affect the best-installed condensate pipework. By insulating the pipework correctly and using components like trace heating kits it is possible to reduce the likelihood of a condensate pipe freezing, although the cost needs to be considered. Externally graded lagging needs to be UV resistant. It is expensive and trace heating kits also can add a noticeable amount to the bill, hence why many installations do not have such equipment installed. 

3. Cheap boilers

Although not technically an installation fault, boilers like this work out far more expensive long run. Boilers such as IQE, Sime, Halstead, Biasi, Ravenheat and other “budget” boilers may seem appealing, but these manufacturers make their money back by building poor quality appliances with components that will fail after a few years and marking up spare parts expensively. It is not uncommon for components from these manufacturers to cost double or triple that what they would cost on other similar boilers spares from brands such as Baxi, Ideal and Worcester.

4. Power flushing

Most companies do not power flush existing systems period. Others that do, do but fail to do it correctly. Most companies do not do it because they need to dedicate a day on average for this process which eats into their profits as they can make more money by installing more boilers. The need to power flush existing systems is the main reason why boilers cannot be installed correctly in one day! In some instances a boiler can be replaced in under 4 hours, however, more often than not, it will take longer to do it correctly, even with two men on the job. The power flushing process will take between 6-8 hours most of the time to complete, although it can take much longer and can not be adequately done until the boiler is fully operational. 

Sludge, scale and any other sediment gets into waterways, valves, pumps and pipes and causes problems. As issues from sludge and scale are accumulative, it can sometimes take several years for the faults to show. 

Modern boilers are prone to faults from sludge and scale, if which boiler manufactures know this, hence why they exclude related faults from their warranties. Manufactures are in the business of making money! A warranty that was invalidated by an installer for one reason or another, such as failing to power flush the system, is better for them as they can charge for the work to put right or refuse to repair it. In such an instance the installer is usually blamed, and the manufacturer denies all accountability while the homeowner is faced with the cost of the repair work and the power flush, often totalling several hundreds of pounds. This is a very common situation. 

We regularly undertake power flushing when fitting new boilers, or where a central heating system is having issues as a result of sludge, scale or sediment. We are leading providers of power flushing in Gloucester, Cheltenham & Tewkesbury. 

When boilers are installed, the process of soldering copper pipework draws flux residues into the pipework of the heating system, which can upset the PH balance of the heating systems water if not removed. As a result, heating system water becomes more acidic and causes a “PH imbalance”. 

A PH imbalance within a central heating system, especially when acidic, will speed up the deterioration of the radiators, seals, expansion vessels membranes, o-rings and anything else that is perishable in the system. Power flushing will help remove these residues and introduce, fresh, clean water to the system.

5. Heating system inhibitors not used.

Inhibitors prevent corrosion within the heating system. Better quality inhibitors also help prevent the formation of limescale and microbial growth. Failing to add inhibitors to the system at the correct dosage will allow for corrosion to take place and invalidate a boilers warranty. All manufacturers specify that inhibitors must be present and at the correct dosage for the warranty to be valid.

6. Using existing radiator valves

Most modern systems are now sealed systems, which are heating systems that are pressurised with water and cut off from the main supply. Like a car tyre, system pressure will drop over time, especially with frequent use as the mechanical joints (components such as o-rings, washers, compression joints and flanges) all over the system pass water. Unless there is a visible water leak this will not be seen it will be so small the water will evaporate unnoticed. 

As mechanical joints age the rate at which water escapes increases, especially on components such as radiator valves which are operated regularly. As the rate of water escaping system increases, the rate that the heating system will need to be “topped up” also increase which. Increased top up frequencies increases the likelihood that boiler will run at low pressure unnoticed. Boilers that are running at lower pressures can be damaged from high bouts of temperature due to air being present in the boiler. Failing to maintain a boiler correctly is excluded from the warranties supplied by manufacturers, and keeping pressure levels as per the manufactures instructions, is part of the maintenance requirements.

Even when a system is flushed old valves can stick as scale, sludge and other sediments present in the water have already passed through the O-ring seals. The power flushing process does not reach here, and this can lead to a situation where radiators fail to operate which is not covered by the boilers warranty.

By having all old and worn radiator valves replaced when a boiler replacement is taking place, the system power flushed correctly and inhibitor levels maintained from this point onwards, the homeowner will ensure many years of trouble-free use from their radiator valves. 

7. Flue Installation 

Vertical flues often lack supports, such as clamps, which in strong wind conditions can lead to the flue coming apart, which is a hazardous situation.  Other required components, such as fire plates and fixing screws, are often not installed.

Flue terminals that are not sited correctly sited can be dangerous and cause problems when the property goes up for sale. FORTHRIGHT regularly encounters flue terminals that have been installed in incorrect positions.

8. Expansion Vessels Sizing 

When a sealed system is installed an expansion vessel is required. Combination boilers and system boilers come with integral expansion vessels; however, they have a finite capacity to how much system water they can support. When a heating systems total water capacity exceeds the capacity of the expansion vessel and the temperature of the system water is raised sufficiently (the heating is operated), the vessel will be subject to pressures beyond what it is designed to operate at, leading to premature failure. In more severe instances, the pressure can rise excessively, leading to regular pressure loss.  Most boilers that have built-in vessels have a vessel that is suitably sized for an average heating system of 7-10 radiators. Many boilers are installed onto heating systems that far exceed this number of radiators, which inevitably lead to problems which will not be covered under a manufactures warranty. In such instances, an additional vessel should be installed close to the boiler.

9. Scale reducers not fitted (combination boilers)

When a scale reducer is not fitted to the main cold supply an area where hard water is present, limescale will accumulate faster in the plated heat exchanger leading to decreased efficiency and the plated heat exchanger eventually failing. The manufactures warranty does not cover this. Scale reducers can reduce the time it takes for limescale to form. It is a mandatory requirement to fit these in areas where tap water sediment exceeds 200PPM. Most heating installers do not own equipment to measure/test the sediment levels in tap water to check if they need to install one or not. 

Most companies have one goal, and that is to make as much money out of a customer as possible. It is easy to believe that you are getting a great deal when a bottom feeding company offers to install a boiler for £1400.00 or a similar ridiculous price, but we and any other company that installs boilers correctly can assure you that it is not profitable for a company to install a good boiler correctly at these prices. 

When you contract FORTHRIGHT to install you a new boiler or central heating system, you do not need not worry about installation defects as we install boilers correctly and protect against it! We refuse to cut corners and fit poor quality appliances. For a boiler or central heating installation in Gloucester, Cheltenham, Tewkesbury our the areas around, contact us for a highly competitive priced, quality install.