diff --git a/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/HealthReportSender.cs b/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/HealthReportSender.cs
index 671ad86f..d5335f08 100644
--- a/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/HealthReportSender.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/HealthReportSender.cs
@@ -140,10 +140,13 @@ public class HealthReportSender : BackgroundService
                 var seq = Interlocked.Increment(ref _sequenceNumber);
 
                 // CollectReport atomically read-and-resets
-                // the per-interval error counters via Interlocked.Exchange. If
-                // the Send below throws, those counts are otherwise lost
-                // forever — neither in the un-sent report nor in the now-zeroed
-                // collector. Snapshot the freshly-collected report so that on a
+                // the per-interval error counters via Interlocked.Exchange. The
+                // transport is now an ACKED round-trip (SendAsync throws on
+                // timeout/nack — review 01 [Medium]), so this restore path is live
+                // rather than dead code. If the SendAsync below throws, those
+                // counts are otherwise lost forever — neither in the un-sent
+                // report nor in the now-zeroed collector. Snapshot the
+                // freshly-collected report so that on a
                 // transport failure we can atomically restore the counts back
                 // into the collector via Interlocked.Add, so the next
                 // successful report includes them. Concurrent increments
@@ -157,7 +160,7 @@ public class HealthReportSender : BackgroundService
 
                 try
                 {
-                    _transport.Send(reportWithSeq);
+                    await _transport.SendAsync(reportWithSeq, stoppingToken).ConfigureAwait(false);
                 }
                 catch
                 {
diff --git a/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/IHealthReportTransport.cs b/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/IHealthReportTransport.cs
index b76ee761..cf4ae906 100644
--- a/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/IHealthReportTransport.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.HealthMonitoring/IHealthReportTransport.cs
@@ -4,13 +4,20 @@ namespace ZB.MOM.WW.ScadaBridge.HealthMonitoring;
 
 /// <summary>
 /// Abstraction for sending health reports to central.
-/// In production, implemented via Akka remoting (Tell, fire-and-forget).
+/// In production, implemented over Akka ClusterClient with an acked round-trip
+/// (review 01 [Medium]): the transport Asks and awaits a
+/// <see cref="SiteHealthReportAck"/>, so a lost/rejected report surfaces as a
+/// fault the sender can observe (and its per-interval counter-restore fires).
 /// </summary>
 public interface IHealthReportTransport
 {
     /// <summary>
-    /// Sends a health report to central (fire-and-forget).
+    /// Sends a health report to central and completes only once central has
+    /// acknowledged processing. MUST THROW on non-delivery (Ask timeout, actor
+    /// system not started, or a not-accepted ack) — the sender's counter-restore
+    /// path in <c>HealthReportSender</c> depends on that exception.
     /// </summary>
     /// <param name="report">The site health report to send.</param>
-    void Send(SiteHealthReport report);
+    /// <param name="cancellationToken">Cancels the in-flight send.</param>
+    Task SendAsync(SiteHealthReport report, CancellationToken cancellationToken);
 }
diff --git a/src/ZB.MOM.WW.ScadaBridge.Host/AkkaHealthReportTransport.cs b/src/ZB.MOM.WW.ScadaBridge.Host/AkkaHealthReportTransport.cs
index 40b59c7d..80ec12b0 100644
--- a/src/ZB.MOM.WW.ScadaBridge.Host/AkkaHealthReportTransport.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.Host/AkkaHealthReportTransport.cs
@@ -6,13 +6,17 @@ using ZB.MOM.WW.ScadaBridge.Host.Actors;
 namespace ZB.MOM.WW.ScadaBridge.Host;
 
 /// <summary>
-/// Sends SiteHealthReport to the local SiteCommunicationActor via Akka ActorSelection.
-/// The SiteCommunicationActor forwards it to central.
+/// Sends SiteHealthReport to the local SiteCommunicationActor via Akka ActorSelection,
+/// which forwards it to central. The send is an acked round-trip (review 01 [Medium]):
+/// it Asks and awaits the central <see cref="SiteHealthReportAck"/>, so a lost or
+/// rejected report faults the sender's task (driving its counter-restore path).
 /// </summary>
 public class AkkaHealthReportTransport : IHealthReportTransport
 {
     private readonly AkkaHostedService _akkaService;
 
+    private static readonly TimeSpan AckTimeout = TimeSpan.FromSeconds(10);
+
     /// <summary>
     /// Initializes a new <see cref="AkkaHealthReportTransport"/> backed by the given Akka hosted service.
     /// </summary>
@@ -23,12 +27,15 @@ public class AkkaHealthReportTransport : IHealthReportTransport
     }
 
     /// <inheritdoc />
-    public void Send(SiteHealthReport report)
+    public async Task SendAsync(SiteHealthReport report, CancellationToken cancellationToken)
     {
-        var actorSystem = _akkaService.ActorSystem;
-        if (actorSystem == null) return;
+        var actorSystem = _akkaService.ActorSystem
+            ?? throw new InvalidOperationException("Actor system not started — health report not sent");
 
         var siteComm = actorSystem.ActorSelection("/user/site-communication");
-        siteComm.Tell(report, ActorRefs.NoSender);
+        var ack = await siteComm.Ask<SiteHealthReportAck>(report, AckTimeout, cancellationToken)
+            .ConfigureAwait(false);
+        if (!ack.Accepted)
+            throw new InvalidOperationException($"Health report #{report.SequenceNumber} rejected: {ack.Error}");
     }
 }
diff --git a/tests/ZB.MOM.WW.ScadaBridge.HealthMonitoring.Tests/HealthReportSenderTests.cs b/tests/ZB.MOM.WW.ScadaBridge.HealthMonitoring.Tests/HealthReportSenderTests.cs
index fc8c26c0..5ea6a969 100644
--- a/tests/ZB.MOM.WW.ScadaBridge.HealthMonitoring.Tests/HealthReportSenderTests.cs
+++ b/tests/ZB.MOM.WW.ScadaBridge.HealthMonitoring.Tests/HealthReportSenderTests.cs
@@ -13,7 +13,11 @@ public class HealthReportSenderTests
     private class FakeTransport : IHealthReportTransport
     {
         public List<SiteHealthReport> SentReports { get; } = [];
-        public void Send(SiteHealthReport report) => SentReports.Add(report);
+        public Task SendAsync(SiteHealthReport report, CancellationToken cancellationToken)
+        {
+            SentReports.Add(report);
+            return Task.CompletedTask;
+        }
     }
 
     private class FakeSiteIdentityProvider : ISiteIdentityProvider
@@ -387,7 +391,7 @@ public class HealthReportSenderTests
         private int _callCount;
         public List<SiteHealthReport> SentReports { get; } = [];
 
-        public void Send(SiteHealthReport report)
+        public Task SendAsync(SiteHealthReport report, CancellationToken cancellationToken)
         {
             var n = Interlocked.Increment(ref _callCount);
             if (n == 1)
@@ -395,6 +399,7 @@ public class HealthReportSenderTests
                 throw new InvalidOperationException("transport temporarily unavailable");
             }
             SentReports.Add(report);
+            return Task.CompletedTask;
         }
     }
 
diff --git a/tests/ZB.MOM.WW.ScadaBridge.Host.Tests/AkkaHealthReportTransportTests.cs b/tests/ZB.MOM.WW.ScadaBridge.Host.Tests/AkkaHealthReportTransportTests.cs
new file mode 100644
index 00000000..9f7ef0d2
--- /dev/null
+++ b/tests/ZB.MOM.WW.ScadaBridge.Host.Tests/AkkaHealthReportTransportTests.cs
@@ -0,0 +1,104 @@
+using Akka.Actor;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging.Abstractions;
+using Microsoft.Extensions.Options;
+using ZB.MOM.WW.ScadaBridge.ClusterInfrastructure;
+using ZB.MOM.WW.ScadaBridge.Commons.Messages.Health;
+using ZB.MOM.WW.ScadaBridge.Commons.Types;
+using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
+using ZB.MOM.WW.ScadaBridge.Communication;
+using ZB.MOM.WW.ScadaBridge.Host.Actors;
+
+namespace ZB.MOM.WW.ScadaBridge.Host.Tests;
+
+/// <summary>
+/// Review 01 [Medium]: the health-report transport is now an ACKED round-trip.
+/// SendAsync completes when central acks Accepted:true, throws when the ack is
+/// not-accepted, and throws when no actor answers (Ask timeout / system not
+/// started) — the fault the sender's counter-restore path depends on.
+/// </summary>
+public sealed class AkkaHealthReportTransportTests
+{
+    private sealed class AckActor : ReceiveActor
+    {
+        public AckActor(bool accepted) => Receive<SiteHealthReport>(r =>
+            Sender.Tell(new SiteHealthReportAck(
+                r.SiteId, r.SequenceNumber, accepted, accepted ? null : "rejected by test")));
+    }
+
+    private static SiteHealthReport SampleReport(long seq = 1) =>
+        new("site-a", seq, DateTimeOffset.UtcNow,
+            new Dictionary<string, ConnectionHealth>(),
+            new Dictionary<string, TagResolutionStatus>(),
+            0, 0, new Dictionary<string, int>(), 0, 0, 0, 0);
+
+    private static AkkaHostedService BuildService(out ActorSystem system)
+    {
+        var port = FreePort();
+        var self = $"akka.tcp://scadabridge@127.0.0.1:{port}";
+        var svc = new AkkaHostedService(
+            new ServiceCollection().BuildServiceProvider(),
+            Options.Create(new NodeOptions { Role = "Site", NodeHostname = "127.0.0.1", RemotingPort = port }),
+            Options.Create(new ClusterOptions
+            {
+                SeedNodes = new List<string> { self },
+                SplitBrainResolverStrategy = "keep-oldest",
+                StableAfter = TimeSpan.FromSeconds(3),
+                HeartbeatInterval = TimeSpan.FromMilliseconds(500),
+                FailureDetectionThreshold = TimeSpan.FromSeconds(2),
+                MinNrOfMembers = 1,
+                DownIfAlone = true,
+            }),
+            Options.Create(new CommunicationOptions()),
+            NullLogger<AkkaHostedService>.Instance);
+        system = svc.GetOrCreateActorSystem();
+        return svc;
+    }
+
+    [Fact]
+    public async Task SendAsync_AckedAccepted_Completes()
+    {
+        var svc = BuildService(out var system);
+        try
+        {
+            system.ActorOf(Props.Create(() => new AckActor(true)), "site-communication");
+            var transport = new AkkaHealthReportTransport(svc);
+            await transport.SendAsync(SampleReport(), CancellationToken.None);
+        }
+        finally { await system.Terminate(); }
+    }
+
+    [Fact]
+    public async Task SendAsync_AckedNotAccepted_Throws()
+    {
+        var svc = BuildService(out var system);
+        try
+        {
+            system.ActorOf(Props.Create(() => new AckActor(false)), "site-communication");
+            var transport = new AkkaHealthReportTransport(svc);
+            await Assert.ThrowsAsync<InvalidOperationException>(
+                () => transport.SendAsync(SampleReport(), CancellationToken.None));
+        }
+        finally { await system.Terminate(); }
+    }
+
+    [Fact]
+    public async Task SendAsync_NoResponder_Throws()
+    {
+        var svc = BuildService(out var system);
+        try
+        {
+            // No actor at /user/site-communication => the Ask times out and faults.
+            var transport = new AkkaHealthReportTransport(svc);
+            await Assert.ThrowsAnyAsync<Exception>(
+                () => transport.SendAsync(SampleReport(), CancellationToken.None));
+        }
+        finally { await system.Terminate(); }
+    }
+
+    private static int FreePort()
+    {
+        var l = new System.Net.Sockets.TcpListener(System.Net.IPAddress.Loopback, 0);
+        l.Start(); var p = ((System.Net.IPEndPoint)l.LocalEndpoint).Port; l.Stop(); return p;
+    }
+}