Backwashing: Difference between revisions

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# Disable the call for heat by lowering the temperature setpoint on the temperature controller to a value several degrees below the sensed temperature (in the future, a switch may be added to do this).

# If the boiler was operating in Step #1, wait for the boiler circulation pump to stop. This may take several minutes. Observe that during this period, the manifold temperature will drop, approaching the boiler inlet (sensed) temperature. It is important to allow the boiler to complete a proper cool-down prior to cutting water circulation. Failure to do so could result in an over-temperature trip, or damage to the boiler itself.

# Stop the main pump motor~~. Switching off~~ the ~~disconnect (the lever~~ on ~~the enclosure above~~ the motor starter~~) may be necessary in some cases (see below)~~.

# Stop the [[Pool Main Pump Motor|main pump motor]] by pressing the Stop button on the motor starter.

NOTE: These steps are identical to the first three followed when [[Cleaning the Strainer Basket#Preparation|cleaning the strainer basket]].

NOTE: These steps are nearly identical to the first three followed when [[Cleaning the Strainer Basket#Preparation|cleaning the strainer basket]].

=== Set ~~Valve Positions~~ ===

=== Set Valves to Backwash ===

The pump must be stopped prior to adjusting the valve positions.

# Open Valve #1

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# Open Valve #3

# Close Valve #4

A valve is open when the lever arm is parallel (in line) with the pipe. A valve is closed when the lever arm is perpendicular (turned 90 degrees with respect to) the pipe.

NOTE: Improved marking and documentation of these valves and positions to follow.

=== Backwash ===

# Start the [[Pool Main Pump Motor|main pump motor]] by pressing the Start button on the motor starter.

# Verify flow is present at the outflow pipe on the north side of the pump house.

# Operate until the water flows clear or 10 minutes has elapsed, which ever occurs first. An excessively long backwash is not recommended as it may result in flushing filter sand into the sanitary sewer.

# Stop the [[Pool Main Pump Motor|main pump motor]] by pressing the Stop button on the motor starter.

The [[Pool Systems Automation#Stack Light|stack light]] indicator should flash an alternating red-green pattern while backwash is active.

Do not turn on pool fill during backwash. It is desired to send as much pool water (versus fresh/city water) to the sanitary sewer as possible.

=== Set Valves to Normal Operation ===

The pump must be stopped prior to adjusting the valve positions.

# Close Valve #1

# Open Valve #2

# Close Valve #3

# Open Valve #4

=== Start Normal Operation ===

# Start the [[Pool Main Pump Motor|main pump motor]] by pressing the Start button on the motor starter.

# Return the temperature controller setpoint to the nominal value (i.e. 82 °F) if adjusted earlier.

# Bleed air from the filter tanks after several minutes of operation.

# Adjust the output flow of the pump to be within 600 to 650 GPM. The flow rate must exceed the required minimum (570 GPM with some margin) but not grossly exceed the combined maximum flow rate of the sand filters (560 GPM). Note that 560 GPM is not a typo; refer to [[Sand Filters]] for discussion on this discrepancy.

@@ Line 19: / Line 19: @@
 # Disable the call for heat by lowering the temperature setpoint on the temperature controller to a value several degrees below the sensed temperature (in the future, a switch may be added to do this).
 # If the boiler was operating in Step #1, wait for the boiler circulation pump to stop.  This may take several minutes.  Observe that during this period, the manifold temperature will drop, approaching the boiler inlet (sensed) temperature.  <b>It is important to allow the boiler to complete a proper cool-down prior to cutting water circulation.  Failure to do so could result in an over-temperature trip, or damage to the boiler itself.</b>
-# Stop the main pump motor.  Switching off the disconnect (the lever on the enclosure above the motor starter) may be necessary in some cases (see below).
+# Stop the [[Pool Main Pump Motor|main pump motor]] by pressing the <b>Stop</b> button on the motor starter.
-NOTE: These steps are identical to the first three followed when [[Cleaning the Strainer Basket#Preparation|cleaning the strainer basket]].
+NOTE: These steps are nearly identical to the first three followed when [[Cleaning the Strainer Basket#Preparation|cleaning the strainer basket]].
-=== Set Valve Positions ===
+=== Set Valves to Backwash ===
+The pump must be stopped prior to adjusting the valve positions.
 # Open Valve #1
@@ Line 29: / Line 31: @@
 # Open Valve #3
 # Close Valve #4
+A valve is open when the lever arm is parallel (in line) with the pipe.  A valve is closed when the lever arm is perpendicular (turned 90 degrees with respect to) the pipe.
+NOTE: Improved marking and documentation of these valves and positions to follow.
+=== Backwash ===
+# Start the [[Pool Main Pump Motor|main pump motor]] by pressing the <b>Start</b> button on the motor starter.
+# Verify flow is present at the outflow pipe on the north side of the pump house.
+# Operate until the water flows clear or 10 minutes has elapsed, which ever occurs first.  An excessively long backwash is not recommended as it may result in flushing filter sand into the sanitary sewer.
+# Stop the [[Pool Main Pump Motor|main pump motor]] by pressing the <b>Stop</b> button on the motor starter.
+The [[Pool Systems Automation#Stack Light|stack light]] indicator should flash an alternating red-green pattern while backwash is active.
+Do not turn on pool fill during backwash.  It is desired to send as much pool water (versus fresh/city water) to the sanitary sewer as possible.
+=== Set Valves to Normal Operation ===
+The pump must be stopped prior to adjusting the valve positions.
+# Close Valve #1
+# Open Valve #2
+# Close Valve #3
+# Open Valve #4
+=== Start Normal Operation ===
+# Start the [[Pool Main Pump Motor|main pump motor]] by pressing the <b>Start</b> button on the motor starter.
+# Return the temperature controller setpoint to the nominal value (i.e. 82 °F) if adjusted earlier.
+# Bleed air from the filter tanks after several minutes of operation.
+# Adjust the output flow of the pump to be within 600 to 650 GPM.  The flow rate must exceed the required minimum (570 GPM with some margin) but not grossly exceed the combined maximum flow rate of the sand filters (560 GPM).  Note that 560 GPM is not a typo; refer to [[Sand Filters]] for discussion on this discrepancy.

Backwashing: Difference between revisions

Matt Parnell (talk | contribs)