The following messages may be shown if errors are present during model simulation. To select and view a pipe with an error, simply click the error value in the Error List Box at the lower right corner of the screen. To select multiple pipes for editing in Pumpsim™, click on the items (hold CTRL to select multiple items) and click SELECT.
Warnings
Warnings can generally be ignored, as the simulation will complete despite the warnings. They may however be a sign of a more serious problem, and should still be investigated.
No entry pipe or surface connection
There is no fluid entering the pipe, therefore no flow can occur. The pipe is not connected to the surface or marked as a ‘closed end’. The program can be set to ignore these warnings in the Settings > Flow Simulation menu.
Resolution – Simply connect a pipe to the entry, connect the pipe to the surface, or marked as a closed end in the Edit Box.
No exit pipe or surface connection
As with no entry warning.
No entry or exit
As with no entry warning description.
Pipe stopping redundant
A pipe stopping has been placed in series with another pipe stopping. Only one stopping is required.
Resolution – None required, although a stopping can be removed if desired.
Pump interfering with another pump
A pump has been placed directly in series with another pump. The pressure imbalance between the pump curves may cause difficulty in resolve the model, particularly if one pump is operating outside of its specified pump curve.
Resolution – Recommend removing a pump, or ensuring an alternative pipe path is available to help ‘bleed’ pressure between pumps.
Stalled pump
The pump is operating at a too high pressure / low volume, beyond the limits of the pump curve.
Resolution – None required, however pumps should not be made to run outside the curve. Pumpsim™ must ‘guess’ a result, which could lead to errors.
Low pressure pump
The pump is operating at too low pressure / high volume, beyond the limits of the pump curve.
Resolution – None required, however pumps should not be made to run outside the curve. Pumpsim™ must ‘guess’ a result, which could lead to errors or water balancing issues. To remove the warning, increase the resistance the pump operates at, or extend the pump curve down to zero pressure.
Negated pump
The pump offering no additional pressure to the model, and may actually be retarding flow.
Resolution – None required, however pumps should not run as negated. Pumpsim™ must ‘guess’ a result, which could lead to errors or water balancing issues. In most cases, pump negation occurs as a result of other pumps drawing water through the pump at a flow above the maximum pump curve quantity. To remove this warning, consider removing or switching off the pump.
Pipe not full
This pipe is after a drain hole, and the drain is not full.
Resolution – None required, however the pressure calculation may not be accurate for this part.
Channel overflow
Too much water flowing down the channel or drain hole too small.
Resolution – None required, but increasing channel or drain size may solve this problem.
Node not connected
A node is not connected to any pipe
Resolution – None required but it may be a design error.
Errors
Errors will generally halt a simulation process, and must be corrected before a valid simulation can occur.
Pipe attempted to reverse
A pipe set as ‘restricted reverse’ in the Edit Box was attempted to be reversed by the simulation. As a result, the simulation is halted.
Resolution – This function is designed to warn the user about pipes which should not have reversed flow. To remove this error, simply unclick the option in the Edit Box for the pipe.
Anomalous pressures
A network design has resulted in a huge buildup of pressure, beyond allowable levels. This causes the simulation calculation to corrupt and breakdown. Because Pumpsim™ uses some of the results of previous simulations for current calculations (for example pump pressures are used to help calculate water density), this may corrupt future simulations as well
Resolution – Allow Pumpsim™ to automatically reset the model. The model can also be manually reset from the Tools Menu. The cause of the pressure buildup should be investigated. It usually stems from overuse or restriction of fixed flow, or too many high resistance (bulkheads) blocking off a working part of the model and restricting flow balancing. Occasionally it may be due to pipes not being connecting properly, restricting movement of water, which can be resolved with the Tools > Filter > Bind command.
Duplicate pipe
A pipe with the same entry and exit location as another pipe has been created.
Resolution – Allow Pumpsim™ to delete the duplicate pipe.
Fixed flow cannot be achieved
A pipe has a fixed flow placed in line with another fixed flow, resulting in a conflict between the two flows, or a fixed flow is placed in a location where it cannot draw water.
Resolution – Remove one of the fixed flows, or ensure a path between the flows exists to balanced the flow difference. Ensure there are no breaks in any pipes leading to or from the fixed flow, through which flow cannot travel.
Fix being over-restricted
A fixed flow encounters too much resistance to flow the required quantity causing a massive buildup in pressure.
Resolution – Check to ensure pathways before and after the fix are connected to the model or surface, and can freely flow, and no blocked resistances are present in the pathways before or after the fix. Pipes that are not exactly connected cannot carry flow. While a no entry/exit warning will normally highlight these pipes, if ‘allow closed end’ has been selected, then no warning will show, and the problem may be difficult to find. Try the wireframe mode with nodes displayed if this is a problem.
Operating pump blocked
A pump has been placed in a pipe through which there could be no flow.
Resolution – As with ‘fix stopped’, check to ensure restricting blocked resistances are not present, and the pipes before and after the pump can carry water.
Convergence problem
The model cannot find a resolution in the model flow balance.
Resolution – Ensure pumps are not running stalled or negated, and no unusual pressures or flows exist within the model.
Temperature outside allowable range
Temperature is increasing or being reduced beyond the allowable range.
Resolution – Investigate what is causing high / low temperatures (eg high heat or refrigeration loads, coupled with low flows). Ensure flow is adequate for heat addition or removal amounts. Reduce heat input if possible, or increase flow.
Heat estimation error encountered
A general error in estimating thermal properties occurred. This normally occurs where water temperatures or pressures are well outside of the expected range.
Resolution – Investigate what is causing high / low temperatures (eg high heat or refrigeration loads, coupled with low flows). Ensure flow is adequate for heat addition or removal amounts. Reduce heat input if possible, or increase flow.
Temp estimation near rock surface
An error estimate transfer of heat flux from rock strata surface to flow. This may happen where an extremely low flow exists, or temperature or moisture values in the water are unusually high or low. Where flow is less than the error correction value in the water simulation settings, Pumpsim™ will not attempt to solve heat balance, and will simply assume the water temperature becomes the same as the virgin rock temperature.
Resolution – Increase flow through pipe, or increase tolerance of mass flow setting in the Settings menu, to ignore pipes with low flow.
Overpressure across resistance
Pressure building up unacceptably over a high resistance pipe, or a pump or fixed flow running into a high resistance pipe.
Resolution – Investigate and remove the source of the high pressure (pump or fix) or remove the high resistance causing the buildup in pressure.
Operating pump restricted by resistance
A resistance has been placed in the same pipe as a pump, and the pump is being unreasonably restricted.
Resolution – Turn the pump OFF instead from the EDIT form, of remove the pump. If the pump is turned OFF, click on SELF CLOSING if you want to ensure water does not leak back through the pump.
Fix being over restricted
Similar to overpressure across resistance, but the error code will target the pipe with the pump or fix, not the resistance.
Resolution – Changing the pump or fix, or alternatively removing the high resistance will correct the problem.
Unresolved pressure or flow
Pumpsim™ cannot resolve of pressure or flow volume during simulation.
Resolution – Ensure no unusually pipes, pump pressure or pathways exist within the model model.
Pump static P curve invalid, check pump
No pump static pressure curve is available for the pump, but a static curve has been selected in the Edit Box or the Settings Menu.
Resolution – Enter a pump static pressure curve for the pump, or ;
change the Edit Box setting to a Pump Total Curve (FTP), or ;
change the Global Pump Pressure method in the Settings Menu to Total Pressure Method.
Pump total P curve invalid, check pump
No pump total pressure curve (FTP) is available for the pump, but a total curve has been selected in the Edit Box or the Settings Menu.
Resolution – Enter a pump total pressure curve for the pump or ;
Change the Edit Box setting to a Pump Static Curve (FSP), or ;
Change the Global Pump Pressure method in the Settings Menu to Static Pressure Method.
Meshing error
Pumpsim™ cannot create a workable mesh of pipe loops (meshes) required for flow and pressure balancing using the Hardy Cross method.
Resolution – Ensure that there are not too many pipes connected to the SURFACE. In addition ensure that pipes are physically connected – use the TOOLS > FILTER option if necessary to allow Pumpsim™ to ensure a connection.
No channel exit
Pumpsim™ cannot find the exit channel.
Resolution – Only one exit channel is allowed, it can be an open end, link to a tank or to a drain hole.
Junction in channel
A junction is present in a channel.
Resolution – Delete junction
A channel cannot be restricted at the exit
A fix flow is present at the end of the channel section.
Resolution – Delete the fix. Fix flow can only be used at the entrance of the channel.
Channel try to reverse
Channel try to reverse during the simulation.
Resolution – Check where the flow try to flow. It could be due to channel with the wrong slope.
Only one downstream channel allowed
Several downstream pipe.
Resolution – Diverging flow are not allowed in Pumpsim™. A way to simulate similar effect can be to separate one of the downstream pipe and to place a fix flow.
No upstream flow entering connection
All the channels are diverging.
Resolution – A channel probably has too high a slope. Adjust the channel or change SETTINGS > SIMULATION > CHANNEL > Minimum Slope so the channel can be considered flat and be reversed.
No downstream connection
All the channels are converging.
Resolution – A channel probably has too high a slope. Adjust the channel or change SETTINGS > SIMULATION > CHANNEL > Minimum Slope so the channel can be considered flat and be reversed.
End of channel missing (surface, tank or drain)
A channel section must have only an end.
Resolution – Specify where the water will flow by putting a surface (with no pump or valve), a tank or a drain at the end of the section.
Too many pipes entering the drain, only one allowed
Only one pipe or channel can enter a drain.
Resolution – Join the pipes before the drain and link to the drain by a small channel section.
Wrong tank connection
Connection with the tank below the water level.
Resolution – Move the channel, tank or water level so the water can enter the tank.