Kibana elasticsearch.hosts setting (7.1)

I have a 3 nodes cluster (version 7.1) in the following nodes:

And kibana is in The setting in the kibana.yml for elasticsearch.hosts is:
elasticsearch.hosts : ["", "", ""].

I can run kibana and see cluster health. But when I stop the elasticsearch in node, I expect kibana to point to other elasticsearch nodes but this is not the case and I get:
"message": "Client request error: connect ECONNREFUSED",
"statusCode": 502,
"error": "Bad Gateway"

Could someone please tell me why I can't connect. The ES documents say elasticsearch.hosts is an array of the elasticsearch hosts.