Hi there - I have a White Knight BG44AW gas dryer which is very similar to yours. There are a couple of reasons why your machine may be cutting out the gas/heat - the first (and easiest) to solve is to check whether the exhaust vent is clear of fluff, not kinked or blocked with anything. As well as clearing the flexible hose check the vent inside the machine is clear as well - clean it out well, the best way is with a vacumm cleaner. This may solve your problem as there is a thermostat in the system to prevent overheating and if the exhaust path is not clear then the machine will overheat and cut the gas/heat off.
If this does not work then you are into a bit more complex repair which should really be carried out by a qualified repairer as it involves gas and the law requires Certified Gas Engineers to carry out such repairs. However, you will be lucky to find someone who will work on a gas tumble dryer as it falls between the two stools of 'Gas fitter' and 'Appliance repairer'. The regulations and certification (which I wholeheartedly agree with) were introduced mainly to qualify and ensure the competence of gas plumbers and heating engineers who work on gas heating, fires and install cookers etc. and really what you need for your tumble dryer is an appliance repair man who is also gas registered and they are as rare as fresh dinosaur eggs in my neck of the woods.
So, having said that, you may have to either throw the machine away or get down and fix it yourself - it is possible but you should be aware that you need to be very careful if you disturb the gas pipe connections to make sure they go back without any leaks !
If your exhaust hose is clear the cause of the intermittent firing will likely be the thermostat probe which sits down into the firing box and controls the heat level of the machine.
Replacement is straightforward but taking the machine to bits to get at it is a real pain in the proverbial as the firing box is right at the bottom of the machine and more or less everything above has to be removed to get at it ... this is not difficult if you are a competent DIY person - the only real tool you need is a cross head screwdriver and an adjustable spanner.
Make sure the machine is unplugged from the electricity and disconnected from the gas. Remove the top lid (three screws at the back and it slides out) you will see the drum inside the case and some electrical connections. You are aiming to take the back panel off the cabinet ideally with the drum still attached to it. There are screws all round the edge of the back and you may have to remove the cover to the back of the flame box to access some of them. You may also need to disconnect the gas feed pipe if this is in the way of removing the back panel and also the panel which secures the vent pipe outlet. Disconnect any electrical connections that will stop the back coming off and ease the drum belt off the motor pulley. It should be possible to slide the drum and the back back panel out from the casing and you wll see the flame box exposed below. The thermostat is clearly visible in the flame box with it's connection to the control box. Replace the thermostat.
Whilst you are there it might be a good idea to look at the condition of the igniter as it's a lot easier to replace it now, if in doubt, than have to take the whole thing apart again. Check the condition of the drum belt whilst you are at it for the same reason !
Putting it all back together is simply a reversal of the dismantling process - it is sometimes difficult to stretch the drum belt back onto the motor pulley - I made up a tubular lever that hooks under the belt and fits over the motor pulley to lever the belt out and then slide it down the tube and onto the pulley but you might manage to stretch it back on if you don't need to replace the belt.
As I said earlier - nothing difficult for a competent DIY person but it looks a bit daunting when you start out. I can't stress enough that, if you are not comfortable with remaking the gas connections properly then you really should look for a competent repairer and at least get your local plumber in to remake the connections when you put it back together and check for any leaks. Gas leaks will kill you.
Best of luck.
Gilesthejob
January 2011
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