Hi, I have a gas fired boiler for a hydronic heating system. I have 3 zones using Honeywell V8043F control valves. I recently replaced one which the guy servicing the boiler said had a short (it was sparking) and all is well with that zone. When the guy was servicing the system he took off the powerheads and lubed the valve stems, all except one powerhead which would not come off. Has anyone experienced this? I can take out the 2 screws which hold the powerhead onto the valve body and wiggle it from side to side but it will not come off. (usually these just lift off easily). I have been very careful not to get too rough with it as i do not want to damage the valve and have to sweat a new one in place. Any ideas?