diff --git a/htdocs/comm/propal/class/propal.class.php b/htdocs/comm/propal/class/propal.class.php
index c633ac44b74..6fa8a2bd379 100644
--- a/htdocs/comm/propal/class/propal.class.php
+++ b/htdocs/comm/propal/class/propal.class.php
@@ -612,7 +612,7 @@ class Propal extends CommonObject
 			}
 			$txlocaltax1 = price2num($txlocaltax1);
 			$txlocaltax2 = price2num($txlocaltax2);
-			$pa_ht = price2num($pa_ht);
+			$pa_ht = price2num($pa_ht);  // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 			if ($price_base_type == 'HT') {
 				$pu = $pu_ht;
 			} else {
@@ -840,7 +840,7 @@ class Propal extends CommonObject
 		}
 		$txlocaltax1 = price2num($txlocaltax1);
 		$txlocaltax2 = price2num($txlocaltax2);
-		$pa_ht = price2num($pa_ht);
+		$pa_ht = price2num($pa_ht);  // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 		if (empty($qty) && empty($special_code)) {
 			$special_code = 3; // Set option tag
 		}
@@ -4234,6 +4234,7 @@ class PropaleLigne extends CommonObjectLine
 		dol_syslog(get_class($this)."::insert rang=".$this->rang);
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float after check if empty value
 
 		// Clean parameters
 		if (empty($this->tva_tx)) {
@@ -4278,9 +4279,6 @@ class PropaleLigne extends CommonObjectLine
 		if (!is_numeric($this->qty)) {
 			$this->qty = 0;
 		}
-		if (empty($this->pa_ht)) {
-			$this->pa_ht = 0;
-		}
 		if (empty($this->multicurrency_subprice)) {
 			$this->multicurrency_subprice = 0;
 		}
@@ -4453,6 +4451,7 @@ class PropaleLigne extends CommonObjectLine
 		$error = 0;
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float after check if empty value
 
 		if (empty($this->id) && !empty($this->rowid)) {
 			$this->id = $this->rowid;
@@ -4507,9 +4506,6 @@ class PropaleLigne extends CommonObjectLine
 		if (empty($this->subprice)) {
 			$this->subprice = 0;
 		}
-		if (empty($this->pa_ht)) {
-			$this->pa_ht = 0;
-		}
 
 		// if buy price not defined, define buyprice as configured in margin admin
 		if ($this->pa_ht == 0 && $pa_ht_isemptystring) {
diff --git a/htdocs/commande/class/commande.class.php b/htdocs/commande/class/commande.class.php
index 26bb1125cbf..2ac0d52671a 100644
--- a/htdocs/commande/class/commande.class.php
+++ b/htdocs/commande/class/commande.class.php
@@ -3130,7 +3130,7 @@ class Commande extends CommonOrder
 			$remise_percent = (float) price2num($remise_percent);
 			$qty = (float) price2num($qty);
 			$pu = price2num($pu);
-			$pa_ht = (float) price2num($pa_ht);
+			$pa_ht = price2num($pa_ht); // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 			$pu_ht_devise = price2num($pu_ht_devise);
 			if (!preg_match('/\((.*)\)/', (string) $txtva)) {
 				$txtva = price2num($txtva); // $txtva can have format '5.0(XXX)' or '5'
@@ -4629,6 +4629,7 @@ class OrderLine extends CommonOrderLine
 		$error = 0;
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float after check if empty value
 
 		// Clean parameters
 		if (empty($this->tva_tx)) {
@@ -4679,9 +4680,6 @@ class OrderLine extends CommonOrderLine
 		if (empty($this->fk_parent_line)) {
 			$this->fk_parent_line = 0;
 		}
-		if (empty($this->pa_ht)) {
-			$this->pa_ht = 0;
-		}
 		if (empty($this->ref_ext)) {
 			$this->ref_ext = '';
 		}
diff --git a/htdocs/compta/facture/class/facture.class.php b/htdocs/compta/facture/class/facture.class.php
index 700f6fac245..00caede5161 100644
--- a/htdocs/compta/facture/class/facture.class.php
+++ b/htdocs/compta/facture/class/facture.class.php
@@ -3877,7 +3877,7 @@ class Facture extends CommonInvoice
 			$pu_ht = price2num($pu_ht);
 			$pu_ht_devise = price2num($pu_ht_devise);
 			$pu_ttc = price2num($pu_ttc);
-			$pa_ht = price2num($pa_ht);
+			$pa_ht = price2num($pa_ht); // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 			if (!preg_match('/\((.*)\)/', (string) $txtva)) {
 				$txtva = price2num($txtva); // $txtva can have format '5.0(XXX)' or '5'
 			}
@@ -4137,7 +4137,7 @@ class Facture extends CommonInvoice
 			$qty			= price2num($qty);
 			$pu 			= price2num($pu);
 			$pu_ht_devise = price2num($pu_ht_devise);
-			$pa_ht = price2num($pa_ht);
+			$pa_ht = price2num($pa_ht); // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 			if (!preg_match('/\((.*)\)/', (string) $txtva)) {
 				$txtva = price2num($txtva); // $txtva can have format '5.0(XXX)' or '5'
 			}
@@ -6256,6 +6256,7 @@ class FactureLigne extends CommonInvoiceLine
 		$error = 0;
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float after check if empty value
 
 		dol_syslog(get_class($this)."::insert rang=".$this->rang, LOG_DEBUG);
 
@@ -6496,6 +6497,7 @@ class FactureLigne extends CommonInvoiceLine
 		$error = 0;
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float after check if empty value
 
 		// Clean parameters
 		$this->desc = trim($this->desc);