That’s that part that confuses me... the manufacture calls for thermal pressure relief(s) but, in fact, there is one on the valve itself. If you do a patent search in Google for patent number 5,143,258, pressure relief for vacuum operated valve, it specifically references this Tokheim Model 52...
The Model 52 PRV is a diaphragm design, specifically needed with above ground tanks to keep tank head pressure off the pump when not pumping. Tank head holds this valve closed until hydraulic suction pressure from the pump acts on the pilot valve and opens the diaphragm. When the pump shuts off...
I’ll try to be thorough as to not leave many questions, hopefully someone is familiar with our above ground tank set up. I am not an engineer but rather a mechanical tech, trying to resolve a problem with our above ground tank diesel dispensing set up. Our company engineers are clueless... We...
