Need to replace Grundfos UPS26-99FC Pump. Returned today to replace Load side pump. Shut off power to system. Shut off water flow to pumps. Removed wiring then removed old pump from flange. Installed new pump onto flange and connected wiring. Opened up water flow to verify no leaks. Purged any air out of line and burped air out of pump. Wrapped insulation around replaced pump and one above it to reduce condensation. Returned power to system and ran heat. Master and hunting zone already calling so I let system run naturally. Geo Load temp started at 95 degrees so I tested unit until setpoint at 125 degrees and all zones satisfied. Unit is operating normal at this time.
Upon arrival I found Geo cube locked out on high pressure. Reset fault and system locked out almost immediately. Found Load Pumps not running or getting voltage. Traced wiring back to cube and found (2) high voltage fuses blown (10amp). Replaced with new but before so we checked pumps. Found lower load pump is grounded. Returned power to system and could see pump sparking. Removed wiring from bad pump but kept power to the other pump so system can remain running. Continued to test and system satisfies in heat mode. This pump was added for ac operation because we didn’t have enough water flow. System will heat with pump down but suggest getting it replaced ASAP. Called WF for warranty status and found pump warranty is 2 year, which ended a few months ago. Quoting customer to replace Load Pump. Customer approved replacing pump, collected deposit. He said they are leaving for vacation on 10/23 and won’t return for a few weeks. If repair could be done before they leave that would be id