diff --git a/src/LSST/M1M3/TS/MPU/FlowMeter.h b/src/LSST/M1M3/TS/MPU/FlowMeter.h
index ff01a04..a91c348 100644
--- a/src/LSST/M1M3/TS/MPU/FlowMeter.h
+++ b/src/LSST/M1M3/TS/MPU/FlowMeter.h
@@ -31,11 +31,16 @@ namespace TS {
 
 /**
  * Reads FlowMeter values.
+ * [Documentation](https://rubinobs.atlassian.net/wiki/spaces/LTS/pages/50081742/Datasheets?preview=/50081742/50505733/FDT40%20Users%20Guide.pdf)
+ * [Datasheets](https://confluence.lsstcorp.org/display/LTS/Datasheets).
  */
 class FlowMeter : public cRIO::MPU {
 public:
     FlowMeter(uint8_t bus) : MPU(bus, 1) {}
 
+    /**
+     * Push calls to readout FlowMeter registers.
+     */
     void readInfo();
 
     uint16_t getSignalStrength() { return getRegister(5500); }
@@ -49,6 +54,9 @@ class FlowMeter : public cRIO::MPU {
     double _getDoubleValue(uint16_t reg);
 };
 
+/**
+ * Add print() method to print readout values.
+ */
 class FlowMeterPrint : public FlowMeter {
 public:
     FlowMeterPrint(uint8_t bus) : FlowMeter(bus) {}
diff --git a/src/LSST/M1M3/TS/MPU/VFD.h b/src/LSST/M1M3/TS/MPU/VFD.h
index c59ccbb..626bf90 100644
--- a/src/LSST/M1M3/TS/MPU/VFD.h
+++ b/src/LSST/M1M3/TS/MPU/VFD.h
@@ -44,12 +44,31 @@ class VFD : public cRIO::MPU {
 
     void readInfo();
 
+    /**
+     * Starts pump - make sure it is running.
+     */
     void start() { presetHoldingRegister(0x2000, 0x1a); }
+
+    /**
+     * Stops pump - stop its motor.
+     */
     void stop() { presetHoldingRegister(0x2000, 0x01); }
+
+    /**
+     * Reset pump state - clear all errors.
+     */
     void resetCommand() { presetHoldingRegister(0x2000, 0x08); }
+
+    /**
+     * Set pump output frequency.
+     */
     void setFrequency(float freq) { presetHoldingRegister(0x2001, freq * 100.0f); }
 
+    /**
+     * Returns pump status.
+     */
     uint16_t getStatus() { return getRegister(0x2000); }
+
     float getCommandedFrequency() { return getRegister(0x2001) / 100.0f; }
 
     uint16_t getVelocityPositionBits() { return getRegister(0x2100); }
diff --git a/src/LSST/M1M3/TS/Telemetry/FlowMeterThread.h b/src/LSST/M1M3/TS/Telemetry/FlowMeterThread.h
index c669bb9..8dc5c74 100644
--- a/src/LSST/M1M3/TS/Telemetry/FlowMeterThread.h
+++ b/src/LSST/M1M3/TS/Telemetry/FlowMeterThread.h
@@ -33,6 +33,10 @@ namespace M1M3 {
 namespace TS {
 namespace Telemetry {
 
+/**
+ * Thread reading out flow meter values. Started from TSPublisher when CSC
+ * enteres disabled state, updates SAL flow meter telemetery.
+ */
 class FlowMeterThread final : public cRIO::Thread, MTM1M3TS_flowMeterC {
 public:
     FlowMeterThread(std::shared_ptr<FlowMeter> flowMeter);
diff --git a/src/LSST/M1M3/TS/Telemetry/PumpThread.h b/src/LSST/M1M3/TS/Telemetry/PumpThread.h
index 68b874b..d8c5b45 100644
--- a/src/LSST/M1M3/TS/Telemetry/PumpThread.h
+++ b/src/LSST/M1M3/TS/Telemetry/PumpThread.h
@@ -34,6 +34,10 @@ namespace M1M3 {
 namespace TS {
 namespace Telemetry {
 
+/**
+ * Thread reading out pump values. Started from TSPublisher when CSC
+ * enteres disabled state, updates SAL VFD pump telemetery.
+ */
 class PumpThread final : public cRIO::Thread, MTM1M3TS_glycolPumpC {
 public:
     PumpThread(std::shared_ptr<VFD> vfd);