diff --git a/esphome/__main__.py b/esphome/__main__.py
index 4b01b5425f..c06b570cb5 100644
--- a/esphome/__main__.py
+++ b/esphome/__main__.py
@@ -245,7 +245,7 @@ def command_vscode(args):
     from esphome import vscode
 
     CORE.config_path = args.configuration
-    vscode.read_config()
+    vscode.read_config(args)
 
 
 def command_compile(args, config):
@@ -423,7 +423,8 @@ def parse_args(argv):
     dashboard.add_argument("--socket",
                            help="Make the dashboard serve under a unix socket", type=str)
 
-    subparsers.add_parser('vscode', help=argparse.SUPPRESS)
+    vscode = subparsers.add_parser('vscode', help=argparse.SUPPRESS)
+    vscode.add_argument('--ace', action='store_true')
 
     return parser.parse_args(argv[1:])
 
diff --git a/esphome/config.py b/esphome/config.py
index 901a78ea9a..671253b31e 100644
--- a/esphome/config.py
+++ b/esphome/config.py
@@ -233,15 +233,19 @@ class Config(OrderedDict):
                 return err
         return None
 
-    def get_deepest_value_for_path(self, path):
-        # type: (ConfigPath) -> ConfigType
+    def get_deepest_document_range_for_path(self, path):
+        # type: (ConfigPath) -> Optional[ESPHomeDataBase]
         data = self
+        doc_range = None
         for item_index in path:
             try:
                 data = data[item_index]
             except (KeyError, IndexError, TypeError):
-                return data
-        return data
+                return doc_range
+            if isinstance(data, ESPHomeDataBase) and data.esp_range is not None:
+                doc_range = data.esp_range
+
+        return doc_range
 
     def get_nested_item(self, path):
         # type: (ConfigPath) -> ConfigType
diff --git a/esphome/config_helpers.py b/esphome/config_helpers.py
index c235371db1..ddad36f8a8 100644
--- a/esphome/config_helpers.py
+++ b/esphome/config_helpers.py
@@ -2,6 +2,7 @@ from __future__ import print_function
 
 import codecs
 import json
+import os
 
 from esphome.core import CORE, EsphomeError
 from esphome.py_compat import safe_input
@@ -9,7 +10,8 @@ from esphome.py_compat import safe_input
 
 def read_config_file(path):
     # type: (basestring) -> unicode
-    if CORE.vscode:
+    if CORE.vscode and (not CORE.ace or
+                        os.path.abspath(path) == os.path.abspath(CORE.config_path)):
         print(json.dumps({
             'type': 'read_file',
             'path': path,
diff --git a/esphome/core.py b/esphome/core.py
index 464782368e..f2bc4fdf2d 100644
--- a/esphome/core.py
+++ b/esphome/core.py
@@ -467,6 +467,7 @@ class EsphomeCore(object):
         self.dashboard = False
         # True if command is run from vscode api
         self.vscode = False
+        self.ace = False
         # The name of the node
         self.name = None  # type: str
         # The relative path to the configuration YAML
diff --git a/esphome/dashboard/dashboard.py b/esphome/dashboard/dashboard.py
index 66ec1e1e54..91370a8194 100644
--- a/esphome/dashboard/dashboard.py
+++ b/esphome/dashboard/dashboard.py
@@ -256,12 +256,12 @@ class EsphomeCommandWebSocket(tornado.websocket.WebSocketHandler):
             self.write_message({'event': 'exit', 'code': returncode})
 
     def on_close(self):
-        # Shutdown proc on WS close
-        self._is_closed = True
         # Check if proc exists (if 'start' has been run)
         if self.is_process_active:
             _LOGGER.debug("Terminating process")
             self._proc.proc.terminate()
+        # Shutdown proc on WS close
+        self._is_closed = True
 
     def build_command(self, json_message):
         raise NotImplementedError
@@ -310,6 +310,11 @@ class EsphomeVscodeHandler(EsphomeCommandWebSocket):
         return ["esphome", "--dashboard", "-q", 'dummy', "vscode"]
 
 
+class EsphomeAceEditorHandler(EsphomeCommandWebSocket):
+    def build_command(self, json_message):
+        return ["esphome", "--dashboard", "-q", settings.config_dir, "vscode", "--ace"]
+
+
 class SerialPortRequestHandler(BaseHandler):
     @authenticated
     def get(self):
@@ -678,6 +683,7 @@ def make_app(debug=False):
         (rel + "clean-mqtt", EsphomeCleanMqttHandler),
         (rel + "clean", EsphomeCleanHandler),
         (rel + "vscode", EsphomeVscodeHandler),
+        (rel + "ace", EsphomeAceEditorHandler),
         (rel + "edit", EditRequestHandler),
         (rel + "download.bin", DownloadBinaryRequestHandler),
         (rel + "serial-ports", SerialPortRequestHandler),
@@ -723,7 +729,7 @@ def start_web_server(args):
 
             webbrowser.open('localhost:{}'.format(args.port))
 
-    if settings.status_use_ping:
+    if not settings.status_use_ping:
         status_thread = PingStatusThread()
     else:
         status_thread = MDNSStatusThread()
diff --git a/esphome/dashboard/static/esphome.js b/esphome/dashboard/static/esphome.js
index 5ec29ba0dd..5a4a89ef5f 100644
--- a/esphome/dashboard/static/esphome.js
+++ b/esphome/dashboard/static/esphome.js
@@ -550,10 +550,75 @@ const editModalElem = document.getElementById("modal-editor");
 const editorElem = editModalElem.querySelector("#editor");
 const editor = ace.edit(editorElem);
 let activeEditorConfig = null;
+let aceWs = null;
+let aceValidationScheduled = false;
+let aceValidationRunning = false;
+const startAceWebsocket = () => {
+  aceWs = new WebSocket(`${wsUrl}ace`);
+  aceWs.addEventListener('message', (event) => {
+    const raw = JSON.parse(event.data);
+    if (raw.event === "line") {
+      const msg = JSON.parse(raw.data);
+      if (msg.type === "result") {
+        console.log(msg);
+        const arr = [];
+
+        for (const v of msg.validation_errors) {
+          let o = {
+            text: v.message,
+            type: 'error',
+            row: 0,
+            column: 0
+          };
+          if (v.range != null) {
+            o.row = v.range.start_line;
+            o.column = v.range.start_col;
+          }
+          arr.push(o);
+        }
+        for (const v of msg.yaml_errors) {
+          arr.push({
+            text: v.message,
+            type: 'error',
+            row: 0,
+            column: 0
+          });
+        }
+
+        editor.session.setAnnotations(arr);
+
+        aceValidationRunning = false;
+      } else if (msg.type === "read_file") {
+        sendAceStdin({
+          type: 'file_response',
+          content: editor.getValue()
+        });
+      }
+    }
+  });
+  aceWs.addEventListener('open', () => {
+    const msg = JSON.stringify({type: 'spawn'});
+    aceWs.send(msg);
+  });
+  aceWs.addEventListener('close', () => {
+    aceWs = null;
+    setTimeout(startAceWebsocket, 5000)
+  });
+};
+const sendAceStdin = (data) => {
+  let send = JSON.stringify({
+    type: 'stdin',
+    data: JSON.stringify(data)+'\n',
+  });
+  aceWs.send(send);
+};
+startAceWebsocket();
+
 editor.setTheme("ace/theme/dreamweaver");
 editor.session.setMode("ace/mode/yaml");
 editor.session.setOption('useSoftTabs', true);
 editor.session.setOption('tabSize', 2);
+editor.session.setOption('useWorker', false);
 
 const saveButton = editModalElem.querySelector(".save-button");
 const saveValidateButton = editModalElem.querySelector(".save-validate-button");
@@ -569,6 +634,19 @@ const saveEditor = () => {
     });
 };
 
+const debounce = (func, wait) => {
+  let timeout;
+  return function() {
+    let context = this, args = arguments;
+    let later = function() {
+      timeout = null;
+      func.apply(context, args);
+    };
+    clearTimeout(timeout);
+    timeout = setTimeout(later, wait);
+  };
+};
+
 editor.commands.addCommand({
   name: 'saveCommand',
   bindKey: {win: 'Ctrl-S',  mac: 'Command-S'},
@@ -576,6 +654,24 @@ editor.commands.addCommand({
   readOnly: false
 });
 
+editor.session.on('change', debounce(() => {
+  aceValidationScheduled = true;
+}, 250));
+
+setInterval(() => {
+  if (!aceValidationScheduled || aceValidationRunning)
+    return;
+  if (aceWs == null)
+    return;
+
+  sendAceStdin({
+      type: 'validate',
+      file: activeEditorConfig
+  });
+  aceValidationRunning = true;
+  aceValidationScheduled = false;
+}, 100);
+
 saveButton.addEventListener('click', saveEditor);
 saveValidateButton.addEventListener('click', saveEditor);
 
diff --git a/esphome/vscode.py b/esphome/vscode.py
index ebbacdf6c7..f0fa4ef52a 100644
--- a/esphome/vscode.py
+++ b/esphome/vscode.py
@@ -1,19 +1,16 @@
 from __future__ import print_function
 
 import json
+import os
 
 from esphome.config import load_config, _format_vol_invalid
 from esphome.core import CORE
 from esphome.py_compat import text_type, safe_input
-from esphome.yaml_util import ESPHomeDataBase
 
 
 def _get_invalid_range(res, invalid):
     # type: (Config, vol.Invalid) -> Optional[DocumentRange]
-    obj = res.get_deepest_value_for_path(invalid.path)
-    if isinstance(obj, ESPHomeDataBase) and obj.esp_range is not None:
-        return obj.esp_range
-    return None
+    return res.get_deepest_document_range_for_path(invalid.path)
 
 
 def _dump_range(range):
@@ -53,13 +50,18 @@ class VSCodeResult(object):
         })
 
 
-def read_config():
+def read_config(args):
     while True:
         CORE.reset()
         data = json.loads(safe_input())
         assert data['type'] == 'validate'
         CORE.vscode = True
-        CORE.config_path = data['file']
+        CORE.ace = args.ace
+        f = data['file']
+        if CORE.ace:
+            CORE.config_path = os.path.join(args.configuration, f)
+        else:
+            CORE.config_path = data['file']
         vs = VSCodeResult()
         try:
             res = load_config()
@@ -67,6 +69,9 @@ def read_config():
             vs.add_yaml_error(text_type(err))
         else:
             for err in res.errors:
-                range_ = _get_invalid_range(res, err)
-                vs.add_validation_error(range_, _format_vol_invalid(err, res))
+                try:
+                    range_ = _get_invalid_range(res, err)
+                    vs.add_validation_error(range_, _format_vol_invalid(err, res))
+                except Exception:  # pylint: disable=broad-except
+                    continue
         print(vs.dump())