Pumps
All about pumps. Please contribute & help complete the article.
Flow & Head
Marketing departments have a habit of claiming flow rate figure with no pipe attached to the output, and head figure at zero flow. These are both unrealistic conditions for real world use. In reality:
- The pump often operates against a column of water (or head) which provides back pressure
- Pipes have resistance to water flow
A better idea of real life flow can be gained by plotting head (at zero flow) versus flow rate (at zero head) on x & y axes, and drawing a line from max flow to max head. This enables approx flow rates to be read off for any given head. Pump curves page explains this.
More Head Please
Plumbing 2 pumps in series increases the flow rate as shown here: Pumps in series
Pump Power
Pump Materials
- Bronze: used for potable water & unsealed uninhibitied CH
- Plastics: some are approved for potable water
- Iron/steel: for central heating where oxygen is excluded or inhibitor used
Connections
Pump Types
Central Heating circulator
- Very quiet operation
- Long service life
- Speed adjustable.
- too fast can cause pumping over & noise
- too slow can cause boiler kettling
- Standardised pipe fittings.
Shower
- Boost shower pressure and thus flow
- Boosts bills too.
Sump pump
- For draining cellars prone to flooding.
- Usually automatically operated by a built-in water sensor
- Usually placed in a small dug out lowered area of floor to achieve good floor drainage.
Drill Pump
- Small minimal cost pump for occasional clear-up use
Foul Water Pump
- Able to handle debris in the water