Different Types of Gas Boilers for your Central Heating System

Types of Gas Boiler Heating Systems

Types of Gas Boilers

If you have the unfortunate problem of a boiler breakdown in winter and you have to replace your gas boiler or you are simply looking to upgrade your gas boiler then there are a few things you need to consider when choosing what type of boiler to install in your home. The size of your boiler, the type, construction, and energy efficiency will all have an impact on your home and your energy bills. You should take some time to consider your options and think carefully about which boiler to choose.

Below is some information on the regular or ‘conventional’ gas boilers, system gas boilers and combination or ‘combi’ gas boilers. (System boilers are very similar to conventional boilers.)


Combi Gas Boilers

A combination or combi boiler is both a high-efficiency water heater and a central heating system boiler in a single compact unit. Combi boilers heat water directly from the mains when you turn on a tap, so you won’t need a hot water storage cylinder or a cold water storage tank in the attic.
They are also very cost-effective and energy-efficient as water is heated instantly rather than being heated and then stored in a cylinder. An added benefit is that hot water is delivered at mains pressure, which means that you could get a powerful shower without the need for a separate pump.







System Gas Boilers

System boilers require a cylinder for storing hot water, however the major heating and hot water system components are built into the boiler itself, making it quicker and easier to install. In addition, there is no need for a tank in the attic, so it can be an option in a home with little or no attic space or where the space is earmarked for a conversion.
These boilers are also compatible with solar water heating systems, which deliver environmental benefits as well as lower energy bills.






Regular Gas Boilers

Regular boilers (sometimes known as conventional or heat only boilers) are ideally suited to homes that already have a traditional central heating and hot water system which is linked to a separate hot water cylinder. These boilers also need a cold water storage tank in the attic to feed the hot water cylinder as well as a tank that maintains the water level of the central heating system.

A regular boiler may be the best option for replacing an existing boiler if the property has an older radiator system, as it might not be able to cope with the higher water pressure that is delivered by system or combi boilers.





Call us Today for a Free Gas Boiler Replacement Quote

We at Dewar Gas & Oil Service are specialist in this field, looking after ten of thousands of customers across Dublin city and surrounding areas. We would be more than happy to send out a directly employed, qualified and fully insured heating engineer to give you a free written quotation for a Gas Boiler Replacement.

Why your boiler makes banging noise when firing up.

Boiler Makes Banging Noise

Boiler Makes Banging Noise

You arrive home and you put on the heating after a long day at the office. You have been thinking about that book you put down on an exciting chapter last night. You try to cosy up on the couch with a cup of tea. You should be at peace but unfortunately you’re disturbed by a strange but constant banging noise, despite being alone in your home. What the hell is that you ask yourself? Well, if there’s no one else in the house banging around. Let’s pray it’s not a burglar, it’s likely then to be your boiler makes banging noise / central heating system.

Your central heating shouldn’t be noisy at all, so if your boiler makes banging noise or any sort of humming, tapping, clicking and gurgling noises then you need to have it investigated. We in the trade call this kettling.


So let’s see what is causing all the fuss?

There are a number of reasons why your boiler makes banging noise but if you’ve just had a new boiler installed; this is likely to be the culprit. Whilst boilers shouldn’t make any noise whatsoever, if they’ve not been installed correctly, they’ll make all sorts of strange sounds.
Other problems can include poorly maintained heating systems and limescale build-ups.


Identifying the noise and problem

Before calling a plumber, we recommend you do some of your own checks. Try to find the location and times the noise starts, ie (is it when your heating just starts up, cools down, when the temperature is turned up higher etc. These are some of the questions the heating plumber will ask you when you phone them up. Below we’ve provided a quick guide to some of the sounds you are likely to hear and what they may mean.


Banging noise coming from the pipes

If you hear a banging or clanging noise, it’s likely to be coming from your pipe work. Check that they have all been fitted and secured with clips or bracketed and tied down properly. If you can see that they are loose or not secured properly, then that’s probably what’s causing those annoying sounds. If the pipes appear to be secured and clipped correctly, then there may be a pressure issue inside the pipes and system. The best thing to do is drain them out and refill the system again. If the banging persists, you will need a plumber, to perhaps power flush the system or install larger pipes for your new boiler.

If your heating thermostats are set at the wrong timing or the system is filled with too much pressure, they may cause your boiler to create a humming sound. To stop this from happening, we recommend checking that your thermostat is working correctly, that the correct water pressure is present (consult the manufacturers manual) it is usually between 1 mbar and 1.5 mbar depending on the system. If it is, it may be a cause of needing to reduce the water pressure, slow down a pump speed that is feeding the heating system.

Please keep in mind that if the pressure is set too high, it can cause damage to your pipes, which is likely to result in them banging and clanging. If you are unsure of any of these it is wise to contact a qualified heating engineer.


Gurgling and tapping noise from the radiators

If you can hear a gurgling or tapping sound coming from your radiators, there’s likely to be a build-up of air inside them. The solution to this problem is pretty simple – you just need to bleed the air out of the system.

To do this, loosen the bleeder screw (ensuring you’ve got a tub underneath, be careful not to open too much the screw could fall out on you) and wait for the water to appear. Once it does, you can be sure that all of the air has gone. Note you may need to top up the heating system if it is a sealed system to the recommended manufacturers water pressure, usually around 1mbar to 1.5mbar.

Tapping sounds can also be caused by lime scale in your radiator pipes also known as kettling. To resolve this issue, you will need to buy a descaling solution to pour into your system. Just make sure your central heating system is turned off beforehand.


Call in a qualified heating plumber

If you do not feel confident in investigating or trying resolve any of these issues yourself, it’s highly recommended that you get in touch with a Registered Gas Installer and or Oil Installer to see if your boiler makes banging noise. We at Dewar Gas & Oil Service are specialists in this field looking after ten of thousands of customers across Dublin city and surrounding areas. We would be more than happy to send out a directly employed, qualified and insured plumber to resolve it for you.

How Often Should a Gas Boiler be Serviced

Gas Boiler

Gas Boiler Maintenance

To ensure a long life for your gas boiler and natural gas appliances, it is important to have them serviced regularly. Appliance manufacturers recommend that all appliances should be serviced annually.

An annual boiler safety checks and gas boiler service are carried out by a professional RGI service engineer ensures that your boiler is functioning properly. Regular servicing of your boiler is important as it ensures that the boiler is working to the specifications designed by the boiler manufacturer. This will help prolong the life of the boiler as well as reduce the risk of faults and expensive repairs down the line.

Gas boiler services can only be carried out by an RGI (registered Gas Installer) who represents the RGII (Registered Gas Installers Ireland).

The Service Engineer will complete 19 detailed checks and tests when carrying out a boiler service. All Visual Checks and Tests Applied are in accordance with Irish Standards 813:2002 as laid down by the National Standards Authority of Ireland for Domestic Gas Installations.

Here you will find a complete gas boiler service checklist which outlines everything that you should expect/demand from your gas contractor when they are servicing your gas boiler.
Annual Gas Boiler Service Checklist.

Reasons to have your Gas Boiler Serviced Annually

Save money on repairs.
Full-blown boiler problems can often develop from minor faults. An annual service will increase the chance that these are picked up on and fixed before they become a problem, saving you money and future gas boiler repairs.

Reduce your heating costs.
The engineer who undertakes your annual boiler service will make sure that it is running as efficiently as possible. This will go a long way towards making sure that you minimise your heating bills.

Carbon monoxide can kill.
Boilers that aren’t properly installed, maintained or ventilated can produce carbon monoxide. Symptoms of carbon monoxide poisoning include headaches, drowsiness, nausea, breathlessness and stomach pains. Signs are hard to spot and can be confused with tiredness or a cold. Unfortunately, this silent killer can’t be seen or smelt, so it really is important to make sure your boiler is serviced at least once a year.

If you’re a landlord, it’s the law.
Landlords have a responsibility under Statutory Instrument SI.534 of 2008 Housing (Standards for Rented Houses) Regulations 2008 to ensure that the gas installation in the house or apartment shall be maintained in good repair and safe working order. The Technical Guidance Document in relation to this Regulation states that a current Declaration of Conformance certificate for an IS.813 Annex E inspection issued by a Registered Gas Installer for the gas installation in the house or apartment will prove compliance with the regulations.

Where is the best place to put a carbon monoxide detector?

Carbon Monoxide Ireland

What is Carbon Monoxide (CO) ?

Carbon Monoxide (also known as CO) is a colourless, odourless poisonous gas and is a common yet preventable cause of death from poisoning worldwide. Approximately half of the deaths from unintentional CO poisoning result from the inhalation of smoke from fires. Other significant causes are vehicle exhausts and deaths in industrial/commercial settings. On average between 1 and 2 people die each year in Ireland from unintentional CO poisoning in the home in incidents related to domestic heating or other fossil fuel installations in the home (i.e. excluding the inhalation of smoke from fires).

The incomplete combustion of organic fossil fuels such as oil, gas or coal is a common environmental source of CO and is responsible for many cases of non-fatal unintentional CO poisoning.

In normal conditions the combustion process (the addition of oxygen) will result in carbon in the fossil fuel, combining with oxygen, in the air, to produce Carbon Dioxide (CO2), the same substance we exhale when we breathe.

However, if there is a lack of air for the combustion process or the heating appliance is faulty, Carbon Monoxide can be produced.

When CO is inhaled into the body it combines with the blood, preventing it from absorbing oxygen. If a person is exposed to CO over a period, it can cause illness and even death.


Where should I place carbon monoxide detectors in my home ?

Since we are most vulnerable to the effects of carbon monoxide poisoning while we sleep, it is important to place alarms near your family’s bedrooms. If you only have one CO alarm, place it as close to everyone’s sleeping area as possible.

Ideally, you should have carbon monoxide detectors placed throughout your home, as you do smoke alarms. You should place a CO detector in each major area of your home: in the kitchen, in your living/dining room, in your bedrooms, and the office. If you have children or elderly family members living with you, provide extra protection near their rooms. If you live in a multi-story home, be sure to place at least one carbon monoxide detector on each level.

If you have a gas clothes dryer, put an alarm in the laundry room. Place one in the garage, if you park your cars there. Wherever you have a solid fuel-fired appliance – anything that could produce carbon monoxide – you should also have a CO alarm.


Carbon Monoxide Poisoning

Causes of CO Poisoning

You can be in danger of Carbon Monoxide poisoning at home if dangerous amounts of Carbon Monoxide accumulate in the home. This can happen as a result of any or a combination of the following:











Symptoms of CO Poisoning

Symptoms of Carbon Monoxide poisoning can be similar to those caused by other illnesses such as a cold or flu. They include





What to Do?

If anyone in your house has any of the symptoms outlined above, they should get fresh air immediately, then go to your doctor and ask him/her to check for Carbon Monoxide poisoning.

Stop using the appliance immediately and do not use it again until it has been checked by a registered gas installer.

The amount of CO which the blood absorbs depends chiefly on two things: how much CO is in the air and the time of the exposure. Adverse effects of CO on humans are reduced by periods of breathing fresh air. The degree of recovery depends on the number and length of those periods. The general state of health and degree of physical activity of a person exposed to CO are other factors involved in the effects of Carbon Monoxide on the body.

Prevention is always better than cure: by having your gas boiler and gas appliances correctly installed in good ventilated areas, properly repaired and getting a gas boiler service annually by Registered Gas Installers (RGI) the risks of being exposed to CO poisoning are reduced.