One of the most popular ways of lining a chimney is by using a stainless steel flexible liner. Most commonly, they are attached to woodburners and multi-fuel stoves and terminate in the chimney pot, underneath the birdguard.
They are a practical way of getting harmful flue gases from your appliance to the outside air.
However, most people don’t understand how to look after their liner, and reports of liner failure are not uncommon. Stainless steel flexible liners are classed as ‘temporary repairs’ – they will fail eventually, as does every flue.
Here’s 5 ways you can play your part in keeping your liner in good condition.
Don’t Burn Wet Wood, Off Cuts or Pallet Wood
Wet wood (i.e. with a moisture content of over 20%) is bad news for liners as it burns at a lower temperature and causes tar build up in the flue. Similarly, off cuts should not be burnt on a domestic appliances. Yes, some think that bits of old fence paneling and pallet wood is ‘free’ fuel. While it may be free at the time, it will cost you more in the long run. The reason is that these are usually full of preservatives or lacquers which, when burnt, go up the liner and stick to the inside of it. This can cause a chimney fire. Don’t do it – stick to dry, seasoned logs.
Don’t Mix Wood & Smokeless Fuel/Coal
The term ‘multi fuel stove’ leads many to think you can burn multiple fuels at the same time. This has been shown to cause liner failure. The reason is that the moisture in the wood (even ‘dry’ wood has around 20% water) combines with sulphurs in the smokeless fuel /coal and can produce an acid which corrodes stainless steel liners. My advice is burn one or the other (depending on your appliance and whether you are in a Smoke Control Zone or not), but not both in equal quantities at the same time.
Use The Correct Fuel Ratio
Check the manufacturers’ instructions – some are very specific on what you can and cannot burn, and in what quantities. Some will specify you can only burn 20% smokeless fuel. It’s worth heeding this advice, particularly as some have warranties and inappropriate fuel usage can make them invalid.
Don’t Slumber Your Stove
This is all to do with the air controls on your stove. If you ‘turn down’ your stove by limiting the air supply, it is known as slumbering. This practice is bad news for your wallet, your liner and the environment. A slumbered appliance causes the fuel to burn at a low temperature (meaning less heat) and also emits more smoke, and therefore more pollution, into the atmosphere. Smoke also condenses in the liner and can produce tar and creosote – one of the big factors in chimney fires. Not only is this very dangerous, it will cost you money either in terms of getting the tar out or paying for a new liner. Burn your fire at the optimum temperature and it’s better all round. See www.burnright.co.uk for further information on this.
Get Your Liner Swept Regularly
It’s is a myth that chimney liners do not need sweeping. In fact, they are more susceptible to failure than some other types of lining so sweeping is essential. Depending on the type of fuel you use and how often, your liner should be swept anywhere up to four times a year. The rule of thumb is generally once a year for seasoned wood used mostly over winter. If you are in a bungalow, then it’s even more important as shorter flues can get sooted up quicker. The best time of year to get a liner swept is over Spring/Summer. Getting it done at this time of year means all the nasty, corrosive soot is not left in just lying there for months and months. Get it swept and help keep your liner in the best condition possible.
Mr Soot Chimney Sweep is a HETAS Approved Sweep, and member of the Guild of Master Chimney Sweeps, offering a professional and friendly chimney sweep and stove service in Wigan, Stockport, Southport, Ormskirk, Chorley and surrounding areas. Book Mr Soot online or call 0800 0541154.