failed taco pump

Tom1

If I have more than one taco-007 pump in my system and one fails

will water pass through the failed pump, or will gravity feed pass

through a idle pump.

Charlie from wmass

only if you have opened the flow check

If you have spring flow checks than no. The gravity flow would not be very much, if any, if on radiant heating due to the small pipes and the long runs. If you have baseboard it will be a little better but still not enough for heat.