diff --git a/src/solver/types.jl b/src/solver/types.jl
index 967cb239bcb..6e92b03104c 100644
--- a/src/solver/types.jl
+++ b/src/solver/types.jl
@@ -385,10 +385,10 @@ Creates a config from the following in order of top priority to last:
 """
 function AtmosCoveragePerfConfig(;
     s = argparse_settings(),
-    config_dict = nothing,
+    config_dict = Dict(),
 )
     parsed_args = parse_commandline(s)
-    if isnothing(config_dict)
+    if !isnothing(parsed_args["config_file"])
         config_dict = YAML.load_file(parsed_args["config_file"])
     end
     target_job_config = if haskey(config_dict, "target_job")
diff --git a/test/config.jl b/test/config.jl
new file mode 100644
index 00000000000..bbca6684a71
--- /dev/null
+++ b/test/config.jl
@@ -0,0 +1,58 @@
+using Test
+import ClimaAtmos as CA
+
+@testset "AtmosCoveragePerfConfig" begin
+    # Just default config overridden by `default_perf.yml`
+    config = CA.AtmosCoveragePerfConfig()
+    # Test defaults overridden by `default_perf`
+    @test config.parsed_args["dt"] == "1secs"
+    # Test defaults not overridden by `default_perf`
+    @test config.parsed_args["y_elem"] == 6
+
+    # Test with `target_job`
+    config = CA.AtmosCoveragePerfConfig(;
+        config_dict = Dict("target_job" => "sphere_baroclinic_wave_rhoe"),
+    )
+    # Target job config overridden by `default_perf`
+    @test config.parsed_args["dt"] == "1secs"
+    # Target job config not overridden by `default_perf`
+    @test config.parsed_args["regression_test"] == true
+
+    # Test that config_file overrides `default_perf`
+    yaml_path = joinpath(
+        @__DIR__,
+        "..",
+        "config",
+        "model_configs",
+        "edmf_soares_jfnk_imex.yml",
+    )
+    args_str = "--config_file " * yaml_path
+    empty!(ARGS)
+    append!(ARGS, split(args_str, " "))
+    config = CA.AtmosCoveragePerfConfig()
+    @test config.parsed_args["dt"] == "50secs"
+    @test config.parsed_args["turbconv_case"] == "Soares"
+
+    empty!(ARGS)
+    # Test that config_dict overrides `default_perf`
+    config_dict = Dict("dt" => "50secs", "turbconv_case" => "GABLS")
+    config = CA.AtmosCoveragePerfConfig(; config_dict)
+    @test config.parsed_args["dt"] == "50secs"
+    @test config.parsed_args["turbconv_case"] == "GABLS"
+
+    # Test that `default_perf` overrides `target_job`
+    config = CA.AtmosCoveragePerfConfig(;
+        config_dict = Dict(
+            "target_job" => "sphere_baroclinic_wave_rhoe",
+            "turbconv_case" => "GABLS",
+        ),
+    )
+    # config_dict
+    @test config.parsed_args["turbconv_case"] == "GABLS"
+    # default_perf
+    @test config.parsed_args["dt"] == "1secs"
+    # target_job
+    @test config.parsed_args["regression_test"] == true
+    # defaults
+    @test config.parsed_args["y_elem"] == 6
+end