diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9ee45a90..a01c3e7d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Fixed <!--Make sure to add a link to the PR and issues related to your change-->
+ - Fixed [#282](https://github.com/Metroscope-dev/metroscope-modeling-library/issues/282) with [#287](https://github.com/Metroscope-dev/metroscope-modeling-library/issues/287), by setting min and max in Positive/Negative MassFlowRate to 0, as it was an unnecessary protection.
  - Fixed [#273](https://github.com/Metroscope-dev/metroscope-modeling-library/issues/273), steam extraction splitter'`x` are lower than 1 [PR#275](https://github.com/Metroscope-dev/metroscope-modeling-library/pull/275)
  - Fixed `IsoHFlowModel` and `IsoPHFlowModel` now use `h_0` as `h` start value with [PR #265]([url](https://github.com/Metroscope-dev/metroscope-modeling-library/pull/265))
  - Fixed `NTU HX` test configuration name for `shell_and_tubes` test, [PR #239](https://github.com/Metroscope-dev/metroscope-modeling-library/pull/239)
diff --git a/MetroscopeModelingLibrary/Units/NegativeMassFlowRate.mo b/MetroscopeModelingLibrary/Units/NegativeMassFlowRate.mo
index 857ec87f..18709fb7 100644
--- a/MetroscopeModelingLibrary/Units/NegativeMassFlowRate.mo
+++ b/MetroscopeModelingLibrary/Units/NegativeMassFlowRate.mo
@@ -1,2 +1,2 @@
 within MetroscopeModelingLibrary.Units;
-type NegativeMassFlowRate=SI.MassFlowRate(max=-1e-5, start=-1e3, nominal=-1e3);
+type NegativeMassFlowRate=SI.MassFlowRate(max=0, start=-1e3, nominal=-1e3);
diff --git a/MetroscopeModelingLibrary/Units/PositiveMassFlowRate.mo b/MetroscopeModelingLibrary/Units/PositiveMassFlowRate.mo
index 4ca2c2c1..f977f55f 100644
--- a/MetroscopeModelingLibrary/Units/PositiveMassFlowRate.mo
+++ b/MetroscopeModelingLibrary/Units/PositiveMassFlowRate.mo
@@ -1,3 +1,2 @@
 within MetroscopeModelingLibrary.Units;
-type PositiveMassFlowRate =
-                         SI.MassFlowRate(min=1e-5, start=1e3, nominal=1e3);
+type PositiveMassFlowRate = SI.MassFlowRate(min=0, start=1e3, nominal=1e3);