* Langeled flows drop to zero, Franpipe sharply down
* Kollsnes output to remain affected until Tuesday
OSLO, Oct 1 (Reuters) - Norwegian gas exports through the Langeled pipeline, the UK's main subsea gas import route, dropped to zero on Monday morning, and flows to France fell sharply as a new "gas year" started.
European gas buyers and sellers adjust supply volumes on Oct. 1 as a new heating season starts in Europe, but analysts said the total drop in Langeled flows suggested technical problems.
Total gas exports to Europe including Britain fell by 66.2 million cubic metres per day to 218.1 mcm at 0730 GMT from the previous day, data from Norway's gas system operator Gassco showed.
Flows through the 71 mcm capacity Langeled pipeline dropped to zero at around 0615 GMT from average 61.3 mcm on Sunday putting total exports to Britain down by 29 mcm, as some losses were offset but higher deliveries through the Vesterled pipeline.
"Langeled flows can drop due to volume adjustment, but not that much. Zero flows suggest technical problems," a gas analyst at Point Carbon said.
Gassco was not immediately available for comment, but it said earlier the Kollsnes gas processing plant, which processes Norwegian gas for export to Britain and continental Europe, will see its output reduced by 40 mcm until Tuesday due to "unexpected problems".
Kollsnes, which has a daily capacity of 147 mcm and processes gas from Norway's biggest field, Troll, was expected to get back to full capacity on Sept. 30.
Statoil , which is the technical service provider at Kollsnes, did not provide any further explanation.
The Vesterled pipeline came back after maintenance around midnight and was pumping 34 mcm of gas per day.
Supplies to France also took a hit with flows through 54 mcm Franpipe pipeline dropping by 33.8 mcm to just 6.4 mcm, while combined exports to the Netherlands and Germany were stable at 124.1 mcm.
Flows to Belgium were down by 3.2 mcm to 36.3 mcm.
The figures are based on gas fed into the system at a certain point in time and calculated to a daily average.
Volumes can change throughout the day as producers adjust the amount of gas they pump into the system.
Norway is the second-biggest pipeline gas supplier to Europe after Russia.
Here are the last spot price settlements on Sept. 28: NBP: 58.6 p/th (25.1 euros/MWh) TTF: 25.8 euros/MWh NCG: 25.9 euros/MWh Gaspool: 25.2 euros/MWh Zeebrugge: 25.2 euros/MWh Peg Nord: 26.2 euros/MWh Peg Sud: 26.6 euros/MWh
Thomson Reuters Point Carbon estimated oil-indexed gas price as of October 1 to be 87.12 pence per therm (37.36 euros per MWh).
(Reporting by Nerijus Adomaitis; editing by Jason Neely)
Keywords: NORWAY GAS/