Water heater combines solar thermal and gas
Hamworthy Heating’s DR-TC water heater combines solar-thermal technology and a condensing gas-fired support. Two models provide outputs of 40 or 60 kW, and they are supplied with a matching solar-transfer station. Trigon solar collectors fit perfectly with the system.
These units fit into a square metre of floor and sidestep the need for an auxiliary heater.
They are based around the Dorchester DR-EC Evo water-heater concept, with an efficient down-firing condensing burner and coiled heat exchanger — but with the addition of a dedicated solar coil for a solar circuit.
The system prioritises the use of solar energy, but will change to gas-fired operation as a high-efficiency back-up when there is not sufficient solar energy to meet demand and to aid with the anti-legionella purge.
Hamworthy can take clients through the whole design and installation process, including commissioning, which is important to set up the system accurately — for example setting the solar temperature differential and hysteresis to ensure the most efficient operation for a particular installation and demand cycle.
