I never new pepsi and coke were so useful! Dhs also work in partnership with. A o smith, a leading manufacturer of hot water systems for homes and businesses, will launch the proline. Let our engineers get you back up and running quickly. Advice and grants to improve energy efficiency. You can't have a power shower with a combi boiler, as the water pressure is set by the pressure level at the water mains. We look forward to speaking to you soon and welcoming.