Frequently Asked Questions

Your frequently asked questions answered. Covering a range of services including heating, plumbing and boilers.

Our ever-expanding community of happy customers.

If you have a question regarding one of our services or about a particular application or product, it is likely someone else also wants to know the answer too and has asked us before. Take a look below at our frequently asked questions and see if it is included. To view the answer, please click the question and it will expand to unveil the answer.

Boiler servicing is not too dissimilar to an MOT on a car. An annual inspection that is there to ensure your vehicle, or in this case your boiler, is safe to use for another year. For more information, please see our full blog post that explains exactly what is included and why it is so important. Alternatively, head to our Boiler Service page for details and pricing.

If your Baxi boiler is showing code E119 then this indicates that your boiler pressure has dropped and the system cannot regulate a constant pressure. Please contact us to arrange for a fully qualified and gas safe registered engineer to come and assess the situation.

Boilers over time lose pressure. This is perfectly normal but it is important to know how to repressurise your boiler to ensure you maintain constant water pressure. Please see our ‘How to repressurise your boiler‘ blog post for information on how to fix low boiler pressure and how to check the pressure going forward so that you can take action before its too late.

A combi boiler or ‘combination’ boiler is a single unit that operates as a high-efficiency water heater whilst also being a central heating boiler. The combi boiler heats water directly from the mains when you turn on the tap meaning you do need need a hot water cylinder or cold water storage tank.

A storage combi boiler is very similar to a traditional combi boiler. Please see ‘What is a combi gas boiler’ for more info in that respect. What makes the storage combi boiler differ is the addition of a hot water cylinder that is located within the boiler unit itself. This helps to maintain a consistent hot water pressure regardless if someone is already using hot water elsewhere in the property.

There are a couple of types of combi boiler that you can get. The most common being either a ‘combi gas boiler’ or a ‘storage combi boiler’. They both have their advantages but it does depend on your own situation. Contact us and we will help you make the right decision.

If you have turned your boiler on but you are finding the radiators are not warming up it could be a couple of things. It could be faulty boiler pump or something not right with your central heating controller. Feel free to contact us if you need us to come and help get your hot water flowing again.

Conventional boilers, or what are also known as condensing boilers differ to condensing boilers in a few ways. One of the main differences of course being due to its function of condensing or lack of. Please see our ‘Conventional and Condensing Boilers – How They Differ‘ featured blog post for more information.

Baxi are a well-known name in the heating industry and have a range of boilers that suit a range of needs and budgets. There are a number of benefits of having a Baxi boiler including extended warranties, same day/ next day repairs and the use of good quality parts. For further information, please see our ‘Baxi Boiler Benefits‘ blog post.


A smart thermostat is much the same as a traditional thermostat but is as it says on the tin ‘smart’. They perform the same core functions but with the addition of complete control over your central heating as well as the option to automate temperature changes. Please see our ‘What is a smart thermostat‘ blog post for further information including a list of advantages they have over traditional thermostats.

It depends on preference but ideal temperatures for homes is somewhere between 18 and 22 degrees centigrade. The lower the temperature, the cheaper your energy bill will be. Please see our ‘5 ways to save money on your energy bills‘ blog post that details a number of ways to save money, including turning your thermostat down by just one degree to save an estimated 10% off your bill.

The main reason why your radiators are turning on but are cold at the bottom is due to a build-up of sludge / debris that has settled within the radiator. If this is the case you will need to have a power flush carried out to clean your system. Please contact us if you would like to know more or to arrange for our fully qualified engineers to attend.  

Both flushes are an effective and thorough way to remove the build-up of dirt, sludge, rust, and debris that has built up over time in the boiler pipework and radiators. The powerflush is more intensive and is recommended for systems which have not been flushed in a long time. Please see our ‘Powerflush vs. Chemical Flush‘ blog post for more information.

It was often thought and assumed that it was more economical to keep your heating on albeit at a low temperature all the time – even when not at home. There were concerns that firing it up every time you got home and needed it cost more as was needing to heat the whole home from scratch each time. This has now been debunked by a range of experts including those at the Energy Saving Trust. For further information, please see our featured blog post.

Energy bills are rising dramatically. However, simple actions can help cut your gas consumption to make your home more efficient and save you money on your heating bill. For a full list of tips, please see our Energy Cost Saving Advice blog post.


There are a number of reasons why your tap might be dripping. Traditional taps tend to drip because of the internal rubber seal or washer has deteriorated over time and requires replacing. It can be difficult to identify where the issue is and what needs replacing. Our fully qualified plumbers are available to stop your leak and stop you from wasting time, water and money. Please head to our contact page to arrange an appointment or call 020 8287 7194.

There are a number of reasons why your sink might be blocked. It is mostly because of a build up of dirt, hair and skin flakes that bind to the soap scum on the inner pipe work. There are preventative measures through regular cleaning but over a blockage is not completely avoidable. If you have a blocked sink and need it clearing, please head to our contact page to arrange an appointment or call 020 8287 7194.


We carry out the installation of all white goods including refrigerators, dishwashers, washing machines, tumble dryers, etc. We also install and connect to the mains, cookers, ovens, and hobs. For the full list, please see our Appliances page.

The fully accredited team at Aren are proficient in the repair of a range of brands and appliances and are always up to date on the latest models available. The various types of appliances that we can repair are detailed on our Appliance page.


A simple but essential component to any home. A device that is often overlooked and do we really know what to look out for or how to test it is working correctly? Please see our ‘How To: Test your carbon monoxide detector‘ blog post that takes you through the various steps as well as what to do in the event of the alarm going off.

The Government Boiler Scheme which is referred to as ECO for short is an initiative set out to help replace old and inefficient boilers with modern equivalents. Please see our ‘Government ECO Boiler Scheme‘ featured blog post for more information.

Landlords & Letting Agents

The CP12 certificate is your evidence that the properties you manage have been checked by a registered Gas Safe engineer in the last twelve months. Not only does the certificate contain details on each of the gas appliances tested, but it also will identify any safety issues that were found during the checks and any action or work needed to ensure safety. If you need a CP12 certificate for a property you manage, please head to our contact page to arrange an appointment or call 020 8287 7194.

The CP12 inspection is comprehensive and incredibly thorough. A summary of some of the checks that will happen during the inspection can be found on our Landlord Certificates page.

Failure to maintain gas appliances is extremely dangerous and illegal. Failing to do so may ultimately result in loss of life.

Not only that, but you risk being prosecuted, and this could result in you facing imprisonment or a fine of up to £20,000.00, for each offence. Or both, if the case is then referred to the Crown Court where the maximum penalty may be imprisonment, an unlimited fine, or both.

If you are a landlord or letting agent, an EPC is required even before the property can be advertised. If a property is rated at F or G in the ‘Minimum Energy Efficiency Standards’ the property cannot be rented out legally. Please see our ‘Landlord’s EPC Responsibilities‘ blog post for more information.

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    Aren Heating & Plumbing

    Trusted and reliable plumbing and heating specialists covering South London, East London and Croydon. Fully qualified.