Free Hydraulic Calculations Program by Alan Ashfield


Demo 2

FREEHC is a new, comprehensive and completely free "Windows" program for the full hydraulic calculations of all types of fire sprinkler fire protection systems to most countries rules and languages as follows :-

Click here to anonymously download the free, complete and latest version of my new FREEHC.EXE program dated 1st January 2016 [754 KBytes].

Just save it to a suitable folder on your hard disk, such as C:\AA3PROGS or C:\FREEHC and there are NO setup / install routines, just the one EXE file direct from my https website which has been checked for viruses / malware etc. It is very similar to my recent FREEWATERMIST program which you can refer to for a more complete explanation of the WALKTHROUGH that follows (using Windows 7) :-

Introduction ...

FREEHC is a very simple, "point and click", fully interactive 3D layout program following any set of Sprinkler Rules and language applicable to your country where you add, break, copy, delete or edit the pipe sections, starting at the water supply out to the operating heads / nozzles in accordance with those Rules and type of system.

Apart from some general data about the job and various design parameters, each pipe is defined by its type, size, length, direction and any fittings / special items starting at the source and working outwards to the heads / nozzles in the protected spaces and you can therefore view plans, elevations or isometrics as you go until all the system has been given whereupon you can do the calculations and see the resulting flows, pressures, velocities etc on those same 3D drawing orientations. Each head / nozzle is grouped under a 'reference' by its size, "K" factor, min/max areas, density (if appropriate), min pressure, U or P type and a description, can be off, on or in any design area with an area of coverage (as needed). I have kept the amount of actual typing to a minimum by offering selections of possible replies that you simply select with the mouse.

Note there are no node numbers to specify and all loops are found automatically so you can quickly and easily create the pipework layout, either all the operating heads / nozzles or just those in the most remote / favourable areas as required. I provide English versions of three different Sprinkler Rules and all the text of the program in separate files as part of FREEHC and these can be retained, added to or amended to suit your own countries requirements and language. I will list here any data files / other language versions that users can Email me for other sprinkler contractors, installers, designers and consultants in your country to download for free. If you wish to view these text-only files before choosing my program, please click on the following links :-

I suggest you start with my four 'Demonstration' examples as these demonstrate all the features of my software and are reset to my original data each time you select them so it does not matter if you make any incorrect changes or edits whilst trying out FREEHC.


When you first run the program, it will automatically download the 3 rules files and the English language text file from my https website (if not already stored) and just show the "File options ..." menu so click on this to see :-


After you click on "Simple DEMO 1 of 4", you will see :-

Demo 1

This is NOT meant to be a real sprinkler system, just a 'starter' drawing so you can quickly become familiar with the various FREEHC options and features. Note that several extra items have appeared on the left hand side including a useful 'Information' area which will identify any problems with the data and a list of pipe quantities with the drawing being an isometric view with the pipe sizes as labels. Click on "Job options ..." to see :-

Job menu

how these menu options work so please select "Project data / design parameters" :-

Project data

Here all the items of project data to identify this job and various design parameters are shown - just press {tab} to move the highlighted bar down the screen to retype the items or the numbers as required. Note that these can all be in your chosen language so click on "Close" to remove it and then on "Head / nozzle / hydrant types" from the same "Job options ..." menu to see :-

Head references

For up to 9 references, you can enter / amend the columns of information with helpful 'hints' across the bottom as needed and leave unused ones as all zero. Click on "Close" to remove it and then on "Database of pipe types etc" from the "Job options ..." menu to view :-

Database page 1

This list has been supplied by me in English for EN12845, NFPA 13/15 and FMGLOBAL sprinkler rules which you can retain, edit, copy, delete as needed for your projects in your own language using this option or 'NotePad' or similar to amend them if more convenient. Just click on the other 3 headings across the top of the screen to see :-

Database page 2 Database page 3 Database page 4

Note how easy it is to create a copy for your specific projects (last question) and the various design parameters needed for any additional sprinkler rules you may require so just click on "Close" now to return to the original screen :-

Demo 1

Click on the "Isometric Bottom Left" and select "Plan" as below :-

View menu

The plan of that same layout will be shown :-


As you move the mouse cursor around, the X and Y position will be confirmed that you may find useful for checking spacings, areas etc. If you now "double-click" on that cursor position, you will see the approx 6m area (as given on the far left option) of pipes / heads around that spot will be 'zoomed in' and shown on screen :-

Zoomed in

You can now choose one of the other isometric views and it will be shown, still zoomed in to that same position (although the pipes you actually see will depend on the aspect ratio of the surrounding pipes and the shape of your screen) :-


Note that the X, Y and Z co-ordinates of the cursor position is given when over any nodes of pipes / heads as this is a 3D view. Just double-click again to "zoom out" and select "Node numbers" from the labels list to see :-

Isometric nodes

The next screen-shot just shows the pipe directions. So using a combination of drawing view, labels, zooming in and out, you can display any possible full size or higher scale picture of your 3D sprinkler system you could ever want, again all in your language, rather than English.


Now please click on "Calculate options ..." and "All heads / nozzles" to see :-

Calculations menu

All the hydraulic calculations have been carried out and balanced to the flow / pressure limits given in the sprinkler rules with the drawing now showing the flow rates in the pipes and at the operating heads / nozzles, with a useful summary under "Information". If you are using the EN12845 Rules or similar, the 4 most remotest heads are shown in bold and the opposite design area (if previously calculated) is shown for reference and added to the IPDS43 data file (program #10 of 20 on the Home page) so that the pump / tank details can be added to determine Qcap/Qmax :-

Calculations done

If you click on the "Flows L/min 90.0>1013.4" label menu you will see a full list of the text items that can be shown on the full size or zoomed in plans, elevations or isometrics :-

Labels menu

and I hope you find it useful to have the minimum / maximum values listed against each item. If you now click on "Calculations options ..." again, you will find two new options listed. The first will create several 2D and 3D .DXF text files for reading into your chosen CAD program (or the free LIBRECAD one). The second option will produce the following screen display :-

CSV form

This will show the 48 columns of input data / results for each pipe so you can either make it full screen or use the horizontal / vertical scroll bars to see the rest of this information, which has also been saved as a 'comma separated variable' (.CSV) file for reading / manipulating in any 'spreadsheet' program you may have (or the free LIBRECALC one). You can also Email your text-based data file(s) to your Reviewer / Approving Agency in your country, who can also download my FREEHC program (in that specific language, if applicable) so they can see ALL the 2D and 3D drawings, labels, views and results in whatever detail they desire. They do not need to ever enter a system as you have to, but just to select "Open" from the "File options ..." menu, choose the appropriate file name and then on "Calculations", "Views" or "Labels", zooming in / out as required - far better and much, much quicker / easier than trying to refer to static lists of numbers and compare them against a drawing plan!

I trust I have now shown you how my FREE program can simply and easily calculate all your future fully hydraulically sprinkler systems that you will ever design and leave you to try out the remaining features and options at your leisure. Pressing the F1 function key will pop-up a screen of help text that describes the pipe data and actions in more detail. Remember these 4 'demonstration' projects are reset to the original set of data every time you select them so you cannot cause any problems by adding or amending their information and the remaining screen-shots show the other three demos below :-

Demo 2

Note the 2 little black squares indicating the junctions of pipes forming 'loops' and the different colours of heads in the two design areas. There is usually little point in drawing all the sprinkler heads fed from a single installation valve as only a reduced number are deemed to be operating at the same time, depending on the hazard/occupancy.

Demo 3

The best way to draw a 'gridded' system as above is to start at the source, go up the 'front track' to the first range / branch line, proceed along it to the junction with the 'back track', then stop and go back to the second range on the front track, copy or draw it out as needed and so on until you have done the furthest range / branch line. You can even do a quick calculation before finishing off the 'back track' from the first / last pipe connections previously left to form one-less loops than there are ranges. There is usually no point in drawing all the heads along the ranges / branch lines as only a reduced number are ever operating, given by 1.2 (sometimes 2) times the square root of the operating area all divided by the head-to-head spacing and rounded upwards (eg. for 260 sq.m this comes to 19.35m so dividing by say 3 m, gives 7 heads/range in the most remote area. You then layout the rest of the heads on the ranges, one by one, going back along the front track with a different number to make up the 260 sq.m or whatever in total as in the above drawing. It is also advisable to arrange for just 1 pipe from the front track to the first head in the range group, then separate pipes between the heads and then again, 1 pipe from the last head to the back track, as this helps in the following operation.

It is therefore necessary to adjust the position of these 7 heads along the range to ensure that approximately half comes from the front track and half from the back track to the most remotest range (not always the last one as you may have elbows at the front track / back track junctions rather than tees or the elevations may be different) to check for the highest pressure from the source, sometimes known as "peaking", although it invariably only makes a few millibars difference and there will never be exactly 50/50% flow split as there is not a head at the hydraulically equidistant point. This is made easier if you have the minimum number of pipes across the range as you just increase / decrease the length of the first pipe from the front track to the first operating head and then decrease / increase the length of the last pipe from the last operating head to the back track.

For the most favouble design area the factor is 1.0 times the square root of the operating area (equals 6 heads/range for my example) so more ranges will be operating in a square shape around the riser entry to the front track than for the most remotest area.

Demo 4

You can study the order of how the pipes were entered on this transformer / oil-tank example by choosing 'pipe numbers' and/or 'fittings' from the labels menu.

Summary of FREEHC :-

Copyright 2016 by Alan Ashfield