The phrase means pumping away from the point of no pressure change. With the pump discharging away from the tank connection, its full head adds to system pressure, which keeps air in solution at the separator, helps top-floor radiators stay full and keeps pump suction well above vapor pressure. It is the first question an experienced hydronics tech asks on a no-heat call with air noises.
Repiped it pumping away from the tank and the gurgling on the third floor stopped the same day.
Also heard as
- pump away
- pump away from the tank
Related terms
Point of no pressure change
The place in a closed hydronic loop, where the expansion tank connects, whose pressure the pump cannot change.
Expansion tank
A closed tank with an air cushion that absorbs the expansion of heating water as it warms up.
Air separator
A hydronic fitting that pulls air bubbles out of circulating water and sends them out through an automatic vent.
Dead men
Steam heating slang for the long-gone engineers and fitters who designed and piped the steam systems that remain in service.