The added problem with this particular boiler is that it's stuck on an ice sheet in the middle of West Antarctica and the manufacturers in Bradford are more than 10,000 miles away on the other side of the world.
It is the second time the main boiler has stopped working on a £7m project to drill through two miles of ice to reach a sub-glacial lake. As was the case first time round, the fault appears to lie with the control circuit of the burner unit to the main boiler, scientists said.
Scientists were hoping by now to have penetrated through the ice cap that has covered Lake Ellsworth for up to a million years. They want to send down probes to retrieve samples of water and mud that could be analysed for signs of life, which could have evolved largely in isolation from the rest of the biosphere.
The boiler, manufactured by Ormandy, was supposed to heat 230 litres of water a minute to a temperature of 90C. This was the amount of hot-water needed to "drill" through the ice and create a borehole to Lake Ellsworth, a body of water the size of Windermere that is prevented from freezing by a combination of geothermal energy and the enormous pressure of the ice cap above.
Scientists from the British Antarctic Survey in Cambridge said that drilling is scheduled to restart at the end of the week when the 12-man team of field scientists will receive a new circuit board, or at least some advice on how to run the boiler manually.
"The technical difficulties are not unfamiliar in Antarctica. It's a very hostile environment and difficult to do things smoothly," said Professor Martin Siegert of Bristol University, the mission's principal investigator.
"The good news is that we found the fault relatively early on in our deployment so we have quite a lot of fuel left remaining. If we didn't have that of course we wouldn't be able to continue any further….we hope to restart drilling in a few days' time," Professor Siegert said.
After the first problem with the boiler last week, a second burner unit successfully fired up for between four and five days, enabling the team to start drilling about 60 metres into the ice before the boiler failed again on Saturday afternoon.
Chris Hill, operations manager for the Ellsworth project, said that an electric element is being used to stop the water in the pipes of the boiler from freezing in the sub-zero temperatures. He said two new circuit boards are being shipped from the UK today. [Wed]
"We have to have a contingency plan in case we need to abandon things but at the moment we still hope to continue the drilling. There's a realistic possibility that we'll still get to the lake by the end of 2012," Mr Hill said.
David Dutch, technical director of Ormandy, said the circuit boards are usually highly reliable but there is a possibility that the two failed units may have both been damaged by the sub-zero temperatures experienced while being stored in the Antarctic over winter.
It would be a huge blow to the scientists if the mission, which has been 15 years in the planning, has to be cancelled because of a boiler problem. Immense effort has gone into the logistics of drilling through 3km of ice with ultra-sterile equipment in order to retrieve microbes that may possibly be unique forms of life.
It would be the first time that scientists have taken pristine samples from one of the hundreds of sub-glacial lakes known to exist in Antarctica. In addition to finding microbial life-forms, the scientists hope that lake sediments will tell them about the past climate of the frozen continent at the end of the world.
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