diff --git a/IBPSA/Fluid/Interfaces/PartialEightPortInterface.mo b/IBPSA/Fluid/Interfaces/PartialEightPortInterface.mo
index d0f37c5a4c..fddc7b6dc3 100644
--- a/IBPSA/Fluid/Interfaces/PartialEightPortInterface.mo
+++ b/IBPSA/Fluid/Interfaces/PartialEightPortInterface.mo
@@ -1,6 +1,6 @@
 within IBPSA.Fluid.Interfaces;
 partial model PartialEightPortInterface
-  "Partial model transporting fluid between eight ports without storing mass or energy"
+  "Partial model with eight ports and declaration of quantities that are used by many models"
   extends IBPSA.Fluid.Interfaces.EightPort;
   parameter Modelica.Units.SI.MassFlowRate m1_flow_nominal(min=0)
     "Nominal mass flow rate" annotation (Dialog(group="Nominal condition"));
@@ -163,7 +163,8 @@ protected
   preferredView="info",
     Documentation(info="<html>
 <p>
-This component defines the interface for models that transport four fluid streams between eight ports.
+This component defines the interface for models with eight fluid ports
+and four fluid streams.
 It is similar to <a href=\"modelica://IBPSA.Fluid.Interfaces.PartialTwoPortInterface\">IBPSA.Fluid.Interfaces.PartialTwoPortInterface</a>,
 but it has eight ports instead of two. </p>
 <p>
@@ -173,6 +174,12 @@ mass transfer and pressure drop equations.
 </html>", revisions="<html>
 <ul>
 <li>
+September 22, 2023, by Michael Wetter:<br/>
+Improved documentation.<br/>
+This is for
+<a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1796\">IBPSA, #1796</a>.
+</li>
+<li>
 February 3, 2022, by Michael Wetter:<br/>
 If <code>allowFlowReversal==false</code>, removed <code>noEvent()</code> declaration
 for <code>sta_a</code> and for <code>sta_b</code> because the variable is either
diff --git a/IBPSA/Fluid/Interfaces/PartialFourPortInterface.mo b/IBPSA/Fluid/Interfaces/PartialFourPortInterface.mo
index 57e60c4262..e1cdf5d257 100644
--- a/IBPSA/Fluid/Interfaces/PartialFourPortInterface.mo
+++ b/IBPSA/Fluid/Interfaces/PartialFourPortInterface.mo
@@ -1,6 +1,6 @@
 within IBPSA.Fluid.Interfaces;
 partial model PartialFourPortInterface
-  "Partial model transporting fluid between two ports without storing mass or energy"
+  "Partial model with four ports and declaration of quantities that are used by many models"
   extends IBPSA.Fluid.Interfaces.PartialFourPort;
   parameter Modelica.Units.SI.MassFlowRate m1_flow_nominal(min=0)
     "Nominal mass flow rate" annotation (Dialog(group="Nominal condition"));
@@ -90,8 +90,8 @@ protected
   preferredView="info",
     Documentation(info="<html>
 <p>
-This component defines the interface for models that
-transport two fluid streams between four ports.
+This component defines the interface for models with four fluid ports
+and two fluid streams.
 It is similar to
 <a href=\"modelica://IBPSA.Fluid.Interfaces.PartialTwoPortInterface\">
 IBPSA.Fluid.Interfaces.PartialTwoPortInterface</a>,
@@ -104,6 +104,12 @@ mass transfer and pressure drop equations.
 </html>", revisions="<html>
 <ul>
 <li>
+September 22, 2023, by Michael Wetter:<br/>
+Improved documentation.<br/>
+This is for
+<a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1796\">IBPSA, #1796</a>.
+</li>
+<li>
 February 3, 2022, by Michael Wetter:<br/>
 If <code>allowFlowReversal==false</code>, removed <code>noEvent()</code> declaration
 for <code>sta_a</code> and for <code>sta_b</code> because the variable is either
diff --git a/IBPSA/Fluid/Interfaces/PartialTwoPortInterface.mo b/IBPSA/Fluid/Interfaces/PartialTwoPortInterface.mo
index 22006b5e01..005324cc55 100644
--- a/IBPSA/Fluid/Interfaces/PartialTwoPortInterface.mo
+++ b/IBPSA/Fluid/Interfaces/PartialTwoPortInterface.mo
@@ -1,6 +1,6 @@
 within IBPSA.Fluid.Interfaces;
 partial model PartialTwoPortInterface
-  "Partial model transporting fluid between two ports without storing mass or energy"
+  "Partial model with two ports and declaration of quantities that are used by many models"
   extends IBPSA.Fluid.Interfaces.PartialTwoPort(
     port_a(p(start=Medium.p_default)),
     port_b(p(start=Medium.p_default)));
@@ -58,8 +58,8 @@ protected
     preferredView="info",
     Documentation(info="<html>
 <p>
-This component defines the interface for models that
-transports a fluid between two ports. It is similar to
+This component defines the interface for models with two fluid ports.
+It is similar to
 <a href=\"Modelica://Modelica.Fluid.Interfaces.PartialTwoPortTransport\">
 Modelica.Fluid.Interfaces.PartialTwoPortTransport</a>, but it does not
 include the species balance
@@ -71,6 +71,13 @@ include the species balance
 Thus, it can be used as a base class for a heat <i>and</i> mass transfer component
 </p>
 <p>
+The partial model extends
+<a href=\"modelica://IBPSA.Fluid.Interfaces.PartialTwoPort\">
+IBPSA.Fluid.Interfaces.PartialTwoPort</a>
+and adds quantities that are used by many models such as
+<code>m_flow_nominal</code>, <code>m_flow</code> and <code>dp</code>.
+</p>
+<p>
 The model is used by other models in this package that add heat transfer,
 mass transfer and pressure drop equations. See for example
 <a href=\"modelica://IBPSA.Fluid.Interfaces.StaticTwoPortHeatMassExchanger\">
@@ -79,6 +86,12 @@ IBPSA.Fluid.Interfaces.StaticTwoPortHeatMassExchanger</a>.
 </html>", revisions="<html>
 <ul>
 <li>
+September 22, 2023, by Michael Wetter:<br/>
+Improved documentation.<br/>
+This is for
+<a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1796\">IBPSA, #1796</a>.
+</li>
+<li>
 February 2, 2022, by Hongxiang Fu:<br/>
 If <code>allowFlowReversal==false</code>, replaced <code>actualStream()</code>
 with <code>inStream()</code> for <code>sta_a</code> and
