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Archive for the Boiler Care Category

What You Should Do After an oil delivery

oil deliveryAfter your oil top up you should wait around 2 hours before firing up your boiler. The reason behind this is that the new oil being delivered will unsettle any crud/water e.t.c. at the bottom of your tank. This can then flow into your oil line and block your filter/pump causing an unnecessary call out. Giving the tank oil time to settle will help prevent this.

If your boiler starts smoking…

If you notice that your boiler is smoking, then, very simply you need to turn it off and call your heating engineer. The problem will not remedy itself!

Turn your boiler off at the controls (programmer/timer), boiler isolation switch or the switch on the boiler itself. It would also be prudent to turn off the supply of oil to the boiler. This can be done at the tank or if you have one, a small isolation valve just inside your boiler casing.

The Fire Valve – An Important Safety Device, Protecting You And Your Home

A Fire-valve is an important safety device on your oil boiler system. Very simply, it shuts off the supply of oil to the boiler should it detect a certain temperature in the boiler casing, i.e. if there’s a fire. It should stop the oil from fueling any fire you have in and around your boiler.

There are two main styles of Fire-valves, Remote action and Handwheel head.

The remote action fire valve is required by OFTEC to be sited on oil lines to all new boiler installations. If an external boiler, this needs to be sited at least 1.5 metres away from the boiler itself. If on an oil line for an internal boiler it needs to be sited outside the property with the phial to be located inside the boiler casing. It should be fitted with the head (bulbous part) on top.


KBB - Fire valve

The Handwheel head style is still used in some modern installations, most notably on HRM Wallstar boilers where it id combined with a non return valve. If you have a Handwheel style fire valve in your boiler casing on a non HRM Wallstar boiler this should be replaced with a remote action fire valve.


Fire valves should be inspected on your annual service and replaced/relocated should they not meet current OFTEC standards.

Note: HRM and OFTEC are not agreed as to the suitability of the Handwheel style recommended on the Wallstar boiler. It is a ‘grey’ area.

Missing An Annual Service Can Affect Your Safety And Cost You More

wasting moneyMissing an annual service does more than costing you money in the long term. There is also safety to consider. When a qualified engineer performs a correctly done service they can check on many things…

Excessive smoke and partially burnt fuel can deposit itself in the heat exchanger in the form of soot, restricting the transfer of heat to the water in the heating system. A clean heat exchanger will transfer more heat giving you better efficiency. According to OFTEC, 3 mm of soot build up can bring about a drop of 8 {91bdfdb8e6beefb03730d8f87ad81b2cee89b80dc73190e0f9e6bd796d0945f5} in efficiency.

Photocells, which detect the light in the heat exchanger(the flame) can glaze over or get specks of dust/soot on them, this can cause the boiler to shut down. Boilers that frequently switch on and off are less efficient than those that run for a longer periods.

Electrodes create the spark that lights the oil/air mix inside your boiler, over time these can become worn and attract soot, if in poor condition, these may not produce the ‘correct’ spark causing the boiler to lock out. Also, if these aren’t positioned correctly, they can cause flame infringement further still lessening the efficiency of the boiler.

Oil nozzles are replaced every 12 months for a reason, they are a consumable that wear over time affecting fuel combustion, they could cause ‘sooting up’ of the heat exchanger due to too much fuel passing through.

Baffle plates, if not cleaned regularly can attract deposits which make it impossible to remove and clean them,again causing a loss in efficiency.

The service allows the engineer the opportunity to inspect the boiler and tank and make it as efficient and safe as possible.

When To Invest In A New Boiler

oil-boilerA shiny new boiler including installation can cost as little as £2000.00, though this is dependent on many factors. They include upgrades that might be needed for the heating system, the quality of boiler installed, the positioning and of course the tradesman.

If your boiler is over 30 years old the likelihood is that it is due for replacement, parts may be difficult and expensive to source and the efficiency won’t be that great.

If you are intending to have an extension, new kitchen e.t.c. then you might want to consider whether your boiler is in the right place for you and where the positioning of a future boiler may have to be. Your current boiler positioning may not be suitable for a new boiler due to flue and fire-valve considerations for example.

If your boiler is breaking down regularly, again, it might be wise to put those call out costs towards a new efficient, reliable boiler.

How Long Should An Oil Boiler Service Take?


On average, a correctly done boiler service should take somewhere between 1 1/2 and 3 hours. Anything less than 1 1/2 hours and a full service has not been carried out. If the service lasts 20 to 30 minutes then you really should be asking yourself what has happened in that time. Would you be happy if your car service took less than an episode of Eastenders?

An ‘easy’ service on a boiler such as a floor standing Thermecon, without a hospitable brew from the householder can be done in 90 minutes whereas a service carried out on a new Worcester combi condensing boiler can take you into the 3 hour zone.

Remember also, that a service should include an inspection of the oil tank, oil-line and heating system as well as the boiler itself.

If you are worried that a service may not of been carried out correctly, please get in touch for advice.

What is a condensing boiler?

condensing-boilerAs of the 1st of April 2005 building regulations state that any new or replacement Oil boiler needs to be a condensing boiler. Only in exceptional circumstances does this not apply.

A condensing oil boiler is a boiler that re-uses previously wasted heat from flue exhaust gases. They will have a bigger heat exchanger or an additional heat exchanger, which allows the water in the water jacket to extract more heat from the exhaust gases than non-condensing boilers.

As the water vapour cools it turns into water (condenses) and leaves the boiler via a condense pipe (and trap) to a suitable termination point.

Condense water is slightly acidic, between 3-5 PH and thus would ‘rot’ ‘old fashioned’ boilers heat exchangers. Condensing boilers are generally made of stainless steel to prevent this. Whilst not great, the slightly acidic nature of the water is no worse than a lot of fizzy drinks.

Know your Oil Boilers!

There are 3 types of Oil Boilers that can be installed and used as a source of hot water

  1. Combi Boiler (or combination boiler).
  2. Regular Boiler (or traditional/conventional boiler).
  3. System Boiler.


Combi boilers provide heating and hot water directly from your boiler whilst regular and system boilers heat your central directly and produce hot water for your domestic hot water cylinder.

Situations where an oil fired combi boiler are best suited include:

  • You live in a flat/bungalow with little or no roof space.
  • You want to convert your loft into an habitable room, requiring the removal of loft tanks.
  • You require hot water ‘on tap’.
  • You have a seperate annex for a family member.


Note: The siting of the combi boiler is very important as it loses efficiency when there are long draw offs (pipe runs to taps, showers e.t.c.).

Situations where an oil fired system/traditional boiler are best suited include:

  • You require a system that allows the use of several draw offs (taps, baths, showers e.t.c.) at once.
  • You have low cold mains pressure coming into the property.
  • Your property has bathrooms, kitchens e.t.c. a long distance from each other and/or boiler siting.


Before selecting a boiler for installation, it is important to discuss your needs with your OFTEC registered oil engineer. Contact us now and let us help you get the right boiler.

Bleeding Air Inside Oil-fired Heating System Radiators

Bleeding a radiator is a fairly straight forward maintenance job, something you can do yourself with just a few tools. Read through the instructions and get your tools together before starting. If you have any doubt or lack the required tools then please feel free to contact us

Step 1

Turn your heating on and wait for the radiators to get hot. This will help you determine which radiators require bleeding. Those with ‘cool spots’  or that don’t heat at the top will be the ones you need to concentrate on.

Step 2

Turn off the heating. Wait awhile until things cool down a little.

Step 3

To bleed the radiators you will need a good quality radiator key such as the one below.

good-radiator-bleed-keyDo not use the style shown below.



Lay down a sheet or towel under the radiator where you are working.

At the top of the radiator on one end is the radiator vent. You need to attach the radiator key to the square bit at the centre of the valve or insert the flat ended part of the screwdriver into the groove.

Keep a clean cloth in one hand near to the vent, hold the key or screwdriver and slowly turn anti-clockwise. you should start to hear a hissing sound, this is the air escaping.

Once water starts to escape, close the vent by turning the key or screwdriver clockwise.

Do not fully unscrew the radiator vent grub screw! If the valve itself starts to turn, tighten it up and then hold it in place with a spanner.

Step 4

If you have a combi or system boiler or your heating system is pressurised, you may need to ‘top up’ the water pressure in your heating system.. You can do this with the relevant taps at the boiler or the lever valves at your filling loop. (please refer to boiler manufacturers instructions).

Spring – The Perfect Time For a Boiler Service

oil-boiler-serviceAs summer approaches and the bitter cold nights of the winter disappear from our mind so do our thought move from our heating to the sunny delights of Bermuda shorts and ice lollies. Spring and summer is the ideal time to have your boiler serviced and/or have work carried out on your heating system. The benefits of having heating work carried out in these months include:

1 -The greater availability of your OFTEC registered engineer (winter months tend to see us busy with breakdowns and emergency boiler replacements).

2- A service can identify potential remedial work and system upgrades which can then be carried out when the need to have the heating turned off won’t affect the household to the degree that it would do during the winter.

3- External Oil boilers should ideally be worked on in the dry as water and electrics don’t mix. Many winter services are called off due to unsuitable weather conditions, i.e. rain leading to a new appointment having to be scheduled.

4- Many engineers increase their prices during the winter months. (NOT US!)

Heating controls


Set your programmer to control both your heating and hot water heating times to suit you and your  lifestyle. If you are out during the day, only have it come on in the morning and in the evening.

Room thermostat

These should be positioned where they won’t be affected by adverse heat/chills from fires, radiators, cat-flaps e.t.c.

Thermostatic radiator valves (T.R.V.)

These are located (if you have them) on one side of your radiators. These control the temperature of your rooms individually. They generally have numbers (1-5) or roman numerals (i-v) on the head. Set these midway to start with and adjust as uyou feel a room needs more or less heat.