Heating ventilation and air conditioning firm Energy Technique (ET) trebled annual profits and said it was on track for another successful year, lifting its shares.Energy Technique, which trades as Diffusion, said pre-tax profit in the year to March 31st increased 225% against the previous year to £649,000 on a 27% rise in sales to £9.6m.Diffusion has supplied fan coils and commercial heating products to the UK heating and ventilation industry for more than half a century.Customers include the likes of Land Securities, Stanhope Properties, Grosvenor Estates and British Land and its products have been used in high-profile London developments such as the Shard, "Cheese Grater" and the "Walkie-Talkie".Commercial heating sales fell marginally in the year ended March 31st 2014, due to a continuation of difficult trading on the UK high street, but ET said order intakes were now improving.It said this financial year had begun well and the group was receiving high levels of fan coil enquiries and improving commercial heating enquiries, together with an improved order book."Whilst it is too early to predict the out-turn for the remainder of the current year ending March 31st 2015, the board looks forward to another successful year," ET said.The group increased its final dividend by 167% to 2p per share.Shares rose 22.5p or 11.4% to 220p by 13:39 in London.PW