Elastic stops search for data

I start the server, add the data to create an index. A couple of days Elastichsearch ceases to find the data that has

Memory becomes full, the provisions of the yield of purified folder data and recreating indexes.

Then we find what you need in the settings to increase the memory allocated by elastiksearch. Set the environment variable export ES_HEAP_SIZE = 10 - is still not looking for data. After rebooting sevrvera $ES_HEAP_SIZE removed

(mongodb) The first time is the right amount of records, but then comes from the server 200 OK response

[
{
"err": "No Living connections"
}
]

What am I doing wrong? Perhaps even other reason? Tell me please