Woodburner maintenance

Some simple recommendations to keep your stove in top shape and avoid expensive repairs

Last week, we took a look at what firewood to use in your wood burning stove. Now we will take a look at how to correctly maintain your wood burner and flue.

As we concluded last week, if a wood burning stove is working correctly and efficiently there should not be much visible smoke coming out of your chimney.

Chimney maintenance

A good start to maintaining your chimney or flue pipe would be to look for smoke. Visible smoke is a sign that the wood stove is running too cold or that the flue may not have been installed properly. Creosote, a black sticky substance that clogs up your chimney, can only be produced when the wood smoke condenses on the inside of a cool chimney. If your stove is burning properly, all the smoke should burn in the firebox. Excess creosote could cause a chimney fire.

Check your manufacturer’s instructions to determine at what temperature your wood burning stove model should burn.

A flue that is too short or is the wrong diameter will not regulate heat or draft as it should. Check your owner’s manual to make sure you have the right flue fit, especially if you are having problems with draft, smoke, and excess creosote.

On top of your free standing wood stove you will typically find a cast iron baffle which lifts off. When the stove is cool, remove the baffle and clean out any ash that may have accumulated. The baffle plate is an intrinsic part of any stove as it ensures that the heat created in the combustion chamber does not escape through the flue but is instead circulated around the stove and emitted efficiently into your room.

Clean your stove thoroughly and remove any accumulated ash. Place a medium sized fan in front of your stove and turn the fan on. The purpose of the fan is to create an updraft in the chimney.

Go to your roof and remove the cap from the flue. You should be able to remove the cap by turning it counter clockwise, then lifting it up.

Brush up and down your flue pipe several times with the chimney brush until there are no more clouds of soot being produced by the brushing action. As your fan is running (see 4.), it will create an updraft that will blow the soot up and out of your chimney.

Remove the stove connector pipe and take it to an area of your home where you can clean it with the same brush you used to clean the flue.

Once you have cleaned everything, put your cap, connector pipe, and the cast iron baffle all back in place.

Ideally should have your chimney swept at least once a year, to ensure everything is okay. If issues are found at a relatively early stage they can be rectified while those left can eventually cause serious damage. Any blockages can also lead to potentially fatal gas escaping into your room.

Stove maintenance

Cracks are not only dangerous but it will also reduce the efficiency of your stove and ultimately increase your heating bill. As soon as a crack is visible on the stove glass, it should be replaced as soon as possible. Contact the shop where you purchased your stove and they should be able to provide you with a replacement glass. Dirty glass can be cleaned with a specific professional cleaning product or vinegar and newspaper will also do the job. Do not use water.

The fire rope around the glass and door of your stove plays a very important role, creating a barrier between your room and the combustion chamber. As soon as the fire rope begins to deteriorate, heat will be leaking into your room in an uncontrolled manner. Over time the deterioration will worsen so its best to change it as soon as possible. Fire rope and glue are extremely cheap but play a very important role. They can be purchased at most hardware stores or shops selling stoves.

A woodburner’s ash pan is placed under significant stress. Ideally wait 24 hours before emptying your ash pan. Many dustbin fires this time of year are due to irresponsible home owners checking them in plastic bins. When emptying is the time to check your ash pan has no holes or evidence of rust.

Fire bricks are an essential part of the stove, effectively deflecting heat back into the centre of the combustion chamber leading to higher temperatures. Over filling of the combustion chamber with wood places more pressure on the fire bricks, leading to cracks and erosion, and more and more heat escaping in an inefficient manner. The erosion of fire bricks and baffle plates will also place greater pressure on the solid metal body of your stove. Under normal circumstances the body of the stove is able to absorb heat at the optimum rate but overheating will over time eventually cause irreparable damage.

Recommendations

Some people think that a stove is an easy cheap way to get rid of their rubbish and heat the house at the same time.

This can be dangerous and damaging to your stove and flue. plastics and even wood coated with varnish may appear to burn easy enough but they create potentially poisonous gases and can also ruin your flue.

Some vegetable peelings, especially potato, should never be burnt either, as they will reduce the stove's efficiency and also create creosote.

You can get a magnetic thermeter

to attach to your flue pipe, this will alert you when the stove overheats. Flue pipes also get damaged due to over fuelling and the excessive heat which this creates.

Aside from the fact that overloading your wood-burning stove with firewood will speed up the erosion of elements such as the baffle plate, flue pipe, fire bricks and cause damage to the body of your stove, it also means you will use more wood in a less efficient manner. The fact that cast iron stove bodies can be impacted by 'overheating' may seem strange to some people but for others it can be a very expensive learning curve!

In case of the stove becoming too hot, close the air inlets to reduce the intensity of the fire.

Woodburning stoves are designed to be used with the door closed. Do not open the door abruptly in order to avoid smoke being released, and never open it without opening the air draught beforehand. Open the door only in order to put in the firewood.

The glass, brass pieces and stove in general may reach very high temperatures. Do not expose yourself to risks of burns and always use protective gloves when reloading with wood.

If you light your fuel from the top down, as the wood slowly burns it will ignite the material below it creating a similar result to those using the bottom-up approach. However, we know maximum efficiency in a wood-burning stove is created when the combustion chamber is as hot as possible. So, as the wood at the top of the pile burns, this quickly heats up the air above allowing the wood below to be burnt.

For the lighting, is recommended you use scrunched up paper, fire lighters or small sticks of wood. Once the fire starts to burn, add to it two logs of wood each weighing 1.5 to 2 kg as a first initial charge. In this lighting process the air inlets of the stove must be kept completely open. If necessary the drawer for removing ashes can also be opened to begin with. Once the fire is more intense, close the drawer completely (if open) and regulate the intensity of the fire by closing the air inlets.

Place the correct amount of wood for your stove (see manufactuers instructions) at intervals of 45 min. The logs should be positioned horizontally and separate from one another, to assure a correct combustion. More wood must not be added to the stove until the previous load has been burnt, leaving only a basic fire bed which is enough to light the next load but no stronger. To achieve a slow combustion you should regulate the fire with the air inlets.

Using the stove at the begining of the cold season

Check there are no flue blockages before relighting fuel after a long period of non-use.

Ideally at the start of each season a professional should carry out a revision of the installation.

Chimney fire

In the event of a fire in the smoke outlet, close all air draughts/inlets if possible and contact the authorities immediately.

Chemical cleaning of your stove and flue

Light your stove and let it burn for 30 minutes, this is to warm up your flue pipe, then put a sachet of flue and chimney cleaner or chimney cleaning log

Leave it to burn, this can be repeated 24 hours later if needed.

If you only use your stove on weekends, all you will need is one sachet of flue and chimney cleaner a week, and one chimney cleaning log a year.

For moderate use (2-3 days a week, 2 or 3 months a year): 2 sachets a week, one log twice a year.

Frequent use: (more than 3 days a week for five months): 3 sachets a week, one log three to give times a year.

Safety recommendations

Get a carbon monoxide alarm (detector/sensor de monoxide de carbóno).