# Gas hot water boilers?



## travelling-man (Jun 17, 2011)

I only have experience of 2 bottled gas hot water boilers. Both were the same make & model & both have the irritating habit of running cold after about 8 minutes......... Is this common with all gas boilers and if not, can anyone recommend one that works properly please?


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## canoeman (Mar 3, 2011)

They all have a tendency to do that, the thermostat overheats so shuts down, then cuts back in when cooled sufficiently, we don't use ours often but get longer than 8 mins, smaller heaters more prone to it, larger models better, but personally I'd look at long term solutions like solar and storage tank, with the view to link all heating options into one overall scheme. 
i.e storage tank with secondary heating coils and sited so can be easily connected to other heat sources, like diesel boiler etc


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## prioryc (Jul 12, 2010)

We had problems for years with boiler going cold after several minutes. Various handy-men and registered gas installers failed to rectify the problem.
Eventually sat in a chair and stared at the boiler thinking things through - went out and bought a longer flue pipe - problem solved!
The issue was with the flue gas temperature - a longer pipe increased the air flow rate meaning cooler gas and the sensor was happy thereafter. The original flue was only around 1m - the new one is over 2m (around 12cm dia).


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## travelling-man (Jun 17, 2011)

Thanks for the tip.... I'll take a look at that when I can find the time! LOL!


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## canoeman (Mar 3, 2011)

Interesting our Vulcano has a recommendation that exit tube should have min 30cm vertical exit then should have an incline of 1cm every metre, unless vertical continued with.


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