[alco33]

Hello thanks for the response. HFS2/3-v3.1 Serial: 102770 Fluke 88 multimeter. I got some time to work on the system and discovered the 20 amp fuse in the main power relay was blown. I replaced the relay and installed an inline fuse holder in a 10 gauge supply line off the battery. Turned it on and it is back to working perfectly. However there is no hint as to why the fuse failed. When I first started the system the fuse was popped ... ... I replaced the fuse and it hasn't failed again until yesterday. Maybe another problem, maybe it's all related ... The system-working-except-no-flow-problem has occurred a couple of times when the pump is working. A flow check at the FAV shows I've got fluid under pressure to the FAV but the gauge doesn't show anything and if I pull the jet while its running there is no fluid. This implies the controller isn't calling for flow or the FAV is getting a call and it isn't responding ... but I've got no way to test further as the system is working perfectly. Every time I've purged the system by pulling the FAV jumper it works perfectly and you can hear the pump go quiet ... all normal, except when there is no flow. Ideas?