replying to MJ, aidan wrote:
sgoulding wrote:

This Grundfos pump is a tankless pump...no external pressure
tank...that is designed to turn on and off per a flow switch. For the
past week or so, the pump has been acting strangely when water is
turned on. This "on demand" pump goes on when a faucet is turned on
but it very consistently shuts off abruptly and turns immediately
back on every 12 seconds or so...4-5 times per minute, every minute,
every time. No matter how many faucets are on.
Has anyone seen this symptom and know if it is repairable or does the
pump need to be replaced?


there is a common fault with these pumps,the mother board gets
faulty,(surging)looking into finding a replacement board
hopefully

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