Surge Reflief Valve not working

Question

Hello, I am trying to model a surge relief valve and I need help. 
 Below is what I have already modeled as an SRV (not SAV). This is to model a residential water supply system where the local pressure gets too high, and a pressure relief valve was installed to reduce the high pressure. 
 
 Issue: When I run the simulation, even though the system pressure at the SRV and surrounding nodes (100psi) is greater than the SRV threshold pressure (90 psi), the output graphs do not show any change in system pressure as it increases beyond the threshold pressure. The SRV does not seem to trigger. 
 What I have already tried: 
 
 Make sure the SRV is 'active' in it's properties 
 Specify valve diameter (4 in.) 
 Vary the spring constant (20-750 lb/in.) 
 Vary threshold pressure 
 Reading the SAV/SRV help pag e: 
 Using an SAV instead 
 Using a Tee setup instead of in-line 
 Make sure my graphs are reading from the correct scenario 
 
 I have also tried to use the example surge relief file , but again the SRV does not seem to affect the system even when the system pressure goes above the SRV threshold pressure. 
 I imagine there is something simple that I am missing, I am new to WaterGEMS and there could be something with the scenarios/graphing that I am doing incorrectly. 
 Please let me know if there is anything else I can do to get the SRV to activate and read out the information on the output graphs. 
 -Kester

Juan Carlos Gutiérrez A. · Accepted Answer

Hi Kester, 
 Surge Relief Valve is an element that should be modeled or analyzed using Hammer. 
 It appears in WaterGEMS due to Hammer and WaterCAD/GEMS data model integration. 
 For steady or quasi-steady analysis this element will remain closed. 
 Rgds, 
 Juan Carlos Gutierrez Araujo

Tom Walski · Answer

If you want to model a surge relief valve with WaterGEMS, you would create a branch link to a Pressure Sustaining Valve (PSV) and you would put a reservoir node at the ground elevations just downstream of the PSV. The setting on the PSV should be the pressure or HGL you want to maintain upstream. 
 This will provide results for steady conditions. If you want to model transients caused by the SRV or determine how the SRV responds to transients, then you need to use HAMMER as Juan Carlos said.