I have a baxi solo 250pf gas boiler that was fitted in a 4 bed detached property before we purchased it with 18 rads & a couple are doubles it doesnt seem to warm the rads very well in this cold weather nor do we get a lot of hot bath water this time of year from a tank that stores constant hot water for heating & domestic supply it seems a rather small boiler for the amount of rads and size of house please could you advise me on a more energy efficient A rated higher output boiler.
Look at http://www.energysavingtrust.org.uk/Publication-Download/?p=1&pid=229 for a rough guide to correct boiler sizing. Your boiler at a mximum output of 14.5kw does sound a little small for the property. Remember to add the required Kw for your thermal store or cylinder.
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