Plumbers North London Islington Plumbing Holloway 24 Plumber Archway Boiler Breakdowns Gas Heating Engineer Finsbury Park

Plumbers North London Islington Plumbing Holloway 24 Plumber Archway Boiler Breakdowns Gas Heating Engineer Finsbury Park

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Worcester Bosh Boilers, Vaillant Combi, Potterton Breakdowns, Glow-worm no hot water, Mira Showers, Baxi Back Boilers, Grundfos Pumps, Biasi, Honeywell Heating Controls Supplied and Fitted

What is "Kettling" in relation to Gas Boilers?

Many people question:



What is Kettling within a Boiler?

A Boiler works by heating hot water via a Heat Exchanger.

In hard water areas, lime scale deposits build up on the heat exchanger and restrict the flow of water.

When the flow of water is restricted (trapped in the heat exchanger) it becomes too hot and starts to steam, boil and therefore expand. This is what causes the noise and sounds like a kettle boiling, hence the name.

Other debris from the system (sludge) can also collect on and around the heat exchanger causing the same problem.

Kettling reduces efficiency and boiler life hence rectifying the situation is actually cost effective as opposed to a wasted outlay of funds.

It is vital to remember that only a Gas Safe registered Heating Engineer \ Plumber can work on your Gas Boiler


Is my boiler going to explode due to kettling?

The boiler has numerous safety controls that should kick in and lock the boiler out (to turn it off) before any kind of explosion occurs.

While it is true that water expands by 1600 times when turning into steam, a combi boiler combats this by having a pressure relief valve and a traditional boiler will make use of the expansion cistern (normally in the loft).

It is however vital for the Plumber to establish the cause of the boiler locking out, diagnose the heat exchanger being at fault and remedy the problem.

Cheaper boiler have smaller heat exchangers so will experience kettling much more frequently then a high standard, top of the range model.


Why is my gas central heating boiler making a rumbling noise?

This is more then likely due to Kettling of the Boiler

This needs to be investigated by a Gas Safe Engineer.


What is the knocking noise coming from my Boiler?

This is more then likely due to Kettling of the Boiler

This needs to be investigated by a Gas Safe Engineer.


Can i cure kettling within my boiler?

Yes kettling is easily prevented & cured!

A kettling boiler can be remedied, prevented from reoccurring and actually could have been prevented from kettling in the first place.


Replacing the Heat Exchanger

Naturally this will be undertaken by a Gas Safe registered engineer and will require the boiler to be stripped and a brand new heat exchanger added removing the issue at hand.

This will normally require the system to be flushed as the new heat exchanger will suffer from debris in the system and before long the problem will occur once again.


Adding liquid inhibitor to the heating system

Otherwise known as a 'system restorer' this can remove some of the lime scale from the heat exchanger and in theory keep it at bay within the system.

This can added via filling loop or radiator within a system containing a combi boiler or straight into the cistern on a traditional system.

Inhibitor should actually have been added before the problem occurred and arguably can cause more damage by creating pin-holes (and therefore leaks) in radiators.


Fitting a Magnetic and Electrolytic Scale Inhibitor

Arguably should actually be fitted upon installation as a prevention tool rather then a cure but should have long term benefits if fitted later.

A scale inhibitor combines two scale inhibiting technologies into one.

The first technology is the use of a magnetic bar to induce a single polarity into the water. This causes the calcium and magnesium (limescale) particles to take on the same polarity.

The particles then repel each other, and as a result prevent the formation of hard limescale. The second technology is the use of zinc plates which create the same reaction as a magnet. Once water passes over the plates and the inner copper body of the unit, a single polarity is induced into the water supply.

This then prevents the formation of hard limescale. In addition, the zinc plates slowly release minute particles into the water supply which prevents corrosion by removing all the air in the system.


Fitting a Spirotech Magnabooster

The SpiroTrap MB2 filters out all types of magnetic and non-magnetic dirt continuously and automatically.

This is achieved by using the units unique dual action SpiroTube separation element and self-cleaning magnet.

Emptying of the unit can be done in seconds by simply opening the release valve.

This is a very efficient solution to a problem that has affected heating systems since they were first introduced.

London Plumbing & Gas fit a Spirotech Magnabooster on every new installation as standard such is the benefit to the customer.


Flushing the system through & Powerflushing

Some of the liquid inhibitors need to be flushed out of a system using clean water as they are aggressive to the system. Equally if a system has no inhibitor it should be flushed before the new liquid inhibitor is added.

Flushing is also an excellent way to pre-commission clean new heating systems, to remove excess flux, swarf and other debris.

Powerflushing is to forcibly cleanse a heating system using water at high velocity, but low pressure, so that no physical damage is caused to the system.

This process should be undertaken using a special machine and system liquids which are now recommended by boiler manufacturers to prolong the life of the boiler and the heating system as a whole.

The objective is to restore systems with circulation and boiler noise problems (caused by sludge and corrosion deposits) to optimum operation and to cleanse a system when fitting a boiler if the existing radiators are to stay.






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