             if app and (app.getAppId() is @appId)
                 app.terminate()
         @_clearTimer()
+        if @ppTimerId
+            clearTimeout @ppTimerId
         @sessionManager.clearReceiverSession()
         @channel.close()
 

            throw new Error "cannot create a ReceiverSession with a null channel!!!"

        super sessionManager, token, appId
        @timeout = Config.RECEIVER_SESSION_TIMEOUT
        @tag = "ReceiverSession"


            interval: Config.RECEIVER_SESSION_PP_INTERVAL
        @_onHeartbeat "ping"
        @triggerTimer()
        @ppTimerId = setInterval ( =>
                @_onHeartbeat "ping"
            ), Config.RECEIVER_SESSION_PP_INTERVAL

