diff --git a/src/core/locale_translations.h b/src/core/locale_translations.h
index f5ce7ce07..12c15bf77 100644
--- a/src/core/locale_translations.h
+++ b/src/core/locale_translations.h
@@ -895,6 +895,8 @@ MAKE_TRANSLATION(cyl3BottomTemp, "cyl3bottomtemp", "third cylinder bottom temper
 MAKE_TRANSLATION(cylTopTemp, "cyltoptemp", "cylinder top temperature (TS10)", "Speichertemperatur oben (TS10)", "", "Cylindertemperatur Toppen (TS10)", "", "", "", "", "", "horná teplota valca (TS10)", "") // TODO translate
 MAKE_TRANSLATION(transferPumpMod, "transferpumpmod", "transfer pump modulation", "Transferpumpenmodulation", "", "Överföringspumpmodulering", "", "", "", "", "", "modulácia prenosového čerpadla", "") // TODO translate
 MAKE_TRANSLATION(transferPump, "transferpump", "transfer pump", "Transferpumpe", "", "Överföringspump", "", "", "", "", "", "prenosové čerpadlo", "") // TODO translate
+MAKE_TRANSLATION(heatAssistOn, "heatassiston", "heat assistance on", "Einschaltdiff. Rücklaufanh.")
+MAKE_TRANSLATION(heatAssistOff, "heatassistoff", "heat assistance off", "Ausschaltdiff. Rücklaufanh.")
 
 // solar dhw
 MAKE_TRANSLATION(wwColdTemp, "coldtemp", "cold water", "Kaltwasser", "", "kallvatten", "zimna woda", "", "", "", "", "studená voda", "studená voda") // TODO translate
diff --git a/src/devices/solar.cpp b/src/devices/solar.cpp
index 6b787ccac..95f8a2861 100644
--- a/src/devices/solar.cpp
+++ b/src/devices/solar.cpp
@@ -417,6 +417,20 @@ Solar::Solar(uint8_t device_type, uint8_t device_id, uint8_t product_id, const c
                               DeviceValueNumOp::DV_NUMOP_DIV10,
                               FL_(swapRetTemp),
                               DeviceValueUOM::DEGREES);
+        register_device_value(DeviceValueTAG::TAG_DEVICE_DATA,
+                              &heatAssistOn_,
+                              DeviceValueType::INT8,
+                              DeviceValueNumOp::DV_NUMOP_DIV10,
+                              FL_(heatAssistOn),
+                              DeviceValueUOM::K,
+                              MAKE_CF_CB(set_solarHeatAssistOn));
+        register_device_value(DeviceValueTAG::TAG_DEVICE_DATA,
+                              &heatAssistOff_,
+                              DeviceValueType::INT8,
+                              DeviceValueNumOp::DV_NUMOP_DIV10,
+                              FL_(heatAssistOff),
+                              DeviceValueUOM::K,
+                              MAKE_CF_CB(set_solarHeatAssistOn));
     }
 }
 
@@ -540,7 +554,8 @@ void Solar::process_SM100Circuit2Config(std::shared_ptr<const Telegram> telegram
 
 // type 0x35C Heat assistance
 void Solar::process_SM100HeatAssist(std::shared_ptr<const Telegram> telegram) {
-    has_update(telegram, solarHeatAssist_, 0); // is *10
+    has_update(telegram, heatAssistOn_, 0);  // is *10
+    has_update(telegram, heatAssistOff_, 1); // is *10
 }
 
 // type 0x361 differential control
@@ -1103,4 +1118,22 @@ bool Solar::set_diffControl(const char * value, const int8_t id) {
     return true;
 }
 
+bool Solar::set_solarHeatAssistOn(const char * value, const int8_t id) {
+    float t;
+    if (!Helpers::value2float(value, t)) {
+        return false;
+    }
+    write_command(0x35C, 0, (uint8_t)(t * 10), 0x35C);
+    return true;
+}
+
+bool Solar::set_solarHeatAssistOff(const char * value, const int8_t id) {
+    float t;
+    if (!Helpers::value2float(value, t)) {
+        return false;
+    }
+    write_command(0x35C, 1, (uint8_t)(t * 10), 0x35C);
+    return true;
+}
+
 } // namespace emsesp
diff --git a/src/devices/solar.h b/src/devices/solar.h
index f6514c0ee..3dceaff31 100644
--- a/src/devices/solar.h
+++ b/src/devices/solar.h
@@ -105,7 +105,8 @@ class Solar : public EMSdevice {
     uint8_t solarPump2Mode_;        // 00=off, 01=PWM, 02=10V
 
     // telegram 0x35C Heat assistance
-    uint8_t solarHeatAssist_; // is *10
+    int8_t heatAssistOn_;  // is *10
+    int8_t heatAssistOff_; // is *10
 
     // telegram 0x035F
     uint8_t cylPriority_; // 0 or 1
@@ -195,6 +196,8 @@ class Solar : public EMSdevice {
     bool set_cylPriority(const char * value, const int8_t id);
     bool set_heatAssist(const char * value, const int8_t id);
     bool set_diffControl(const char * value, const int8_t id);
+    bool set_solarHeatAssistOn(const char * value, const int8_t id);
+    bool set_solarHeatAssistOff(const char * value, const int8_t id);
 };
 
 } // namespace emsesp
diff --git a/src/web/WebCustomEntityService.cpp b/src/web/WebCustomEntityService.cpp
index b489a9bc5..8f34b0123 100644
--- a/src/web/WebCustomEntityService.cpp
+++ b/src/web/WebCustomEntityService.cpp
@@ -196,7 +196,7 @@ bool WebCustomEntityService::command_setvalue(const char * value, const int8_t i
                 if (!Helpers::value2float(value, f)) {
                     return false;
                 }
-                int v = f / entityItem.factor;
+                int v = (f / entityItem.factor + 0.5);
                 if (entityItem.value_type == DeviceValueType::UINT8 || entityItem.value_type == DeviceValueType::INT8) {
                     EMSESP::send_write_request(entityItem.type_id, entityItem.device_id, entityItem.offset, v, 0);
                 } else if (entityItem.value_type == DeviceValueType::UINT16 || entityItem.value_type == DeviceValueType::INT16) {