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Grant/Chofu fault codes
Without heating over the weekend ☹️
WiFi Nest tells me it's heating but the radiators are stone cold.
Checked the controller in the garage and got P1.
Done the recommendations reset on the controller and the HP but cannot fix. Only thing I haven't got is a multimeter and the only 'experiment' I did recently was to try the heating on schedule with a one degree variance, but don't think this could have affected?
Will be 🤙 Grant in the morning for technical support but looks like I'm gonna need a new PCB or a pump
Anyone else had this experience?
2 10kw Grant Aerona3
Heat loss calc 16.5 kw @ -2.8 degrees
4.32 PV
Sorry, no. My Grant has only died once and that was me causing the RCBO to trip. If the fault reset didn't work (and assume you also tried the all-powerful "turn it off then back on again") then it might be the main PCB, as suggested.
Amending the heating demand shouldn't have any damaging impact on the HP.
Hope Grant can sort you out. Good luck.
Grant Aerona 3 10kW
@mikefl rang technical this morning and they suggested 1st to raise the pressure and then bleed the radiators if no joy from that then engineer to inspect and either clear out any debris or replace the pump/pcb 🫤 another 24/48 hours without heating and hot water .
2 10kw Grant Aerona3
Heat loss calc 16.5 kw @ -2.8 degrees
4.32 PV
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