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AIR CONDITIONING & HEAT PUMP SYSTEMS
BACKDRAFTING HEATING EQUIPMENT
BACKUP HEAT for HEAT PUMPS
BANGING HEATING PIPES RADIATORS
BLOWER FAN OPERATION & TESTING
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
CARBON MONOXIDE - CO
CIRCULATOR PUMPS & RELAYS
DIAGNOSTIC GUIDES A/C / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS
ELECTRIC MOTOR DIAGNOSTIC GUIDE
FAN, AIR HANDLER BLOWER UNIT
FLOODED HEATING EQUIPMENT REPAIR
FLUE SIZE SPECIFICATIONS
GAS BURNER Flame & Noise Defects
GAS PIPING, VALVES, CONTROLS
GEOTHERMAL HEATING SYSTEMS
HEAT PUMPS, DIAGNOSIS, REPAIR
HEATING COST SAVINGS METHODS
HEATING OIL PIPING TROUBLES
HEATING OIL TANKS
HEATING SYSTEM NOISES
HEATING SYSTEM TYPES
GAS LP & NATURAL GAS SAFETY HAZARDS
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH
NOISE, HEATING SYSTEMS
ODORS FROM HEATING SYSTEMS
OIL FILTERS on HEATING EQUIPMENT
OIL FILL PIPE LEAKS
OIL SPILL CLEANUP / PREVENTION
PLASTIC Plexvent / Ultravent RECALL
PUFFBACKS, OIL BURNER
RELIEF VALVE LEAKS
Reset Switch - Heater Primary Control
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY, HEATING INSPECTION
SAFETY RECALLS CHIMNEYS VENTS HEATERS
SOLAR HEATING SYSTEM DESIGNS
SOOT on OIL FIRED HEATING EQUIPMENT
STEAM HEATING SYSTEMS
THERMOSTATS, HEATING / COOLING
VIDEO GUIDES: Heating System Videos
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
ZONE VALVES, HEATING
Where to put the circulator pump on hot water heating systems: Here we explain where the circulating pump can or should be mounted on a hot water or hydronic heating boiler.
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
At left our photo shows the heating zone circulators mounted on the return-side of a Weil McLain heating boiler. If you click to enlarge the photograph you can see the supply and return piping in more detail.
[Click to enlarge any image]
Similarly, the heating boiler piping diagram at page top, courtesy of Raypak® shows the heating system circulator pump assembly (red in our sketch) on the return or inlet side of the heating boiler.
We often receive the question "Where should the heating boiler circulator pump be mounted: on the supply or boiler outlet side (the hot side) or on the return or boiler inlet side (the cool side) of the heating piping loop?"
Read the instructions: The short answer is, mount the circulator and arrange all other piping and controls according to the boiler manufacturer's installation and operating instructions and you won't go wrong.
A sample boiler installation and operation manual that is particularly clear and easy to follow is provided by Raypac® but of course you should obtain and follow the instructions from the maker of your particular boiler maker.
Locating the Circulator Pump on the Boiler Return or "cold" or "inlet" side
On the boiler return or inlet side: most but not all residential heating boilers and probably most commercial heating boilers mount the circulator pump on the return or inlet side of the heating boiler.
This location is a traditional one preferred by some old-school boiler installers and service people, dating from a time when a boiler came from the manufacturer without the circulator pre-installed on piping attached to the unit.
Some heating service technicians (including the web publisher) opine that the cooler heating water temperature on the return side of the boiler means that the circulator pump and its bearings may have a longer life than if installed on the hot side.
Typically heating water returning to a boiler after circulating through a building is about 20 °F. cooler than water leaving the boiler. The heating boiler piping diagram at page top, courtesy of Raypak® shows the heating system circulator pump assembly (red in our sketch) on the return or inlet side of the heating boiler.
By piping convention the triangle (which we surrounded in red for emphasis) points down, showing the direction of water flow.
Locating the Circulator Pump on the Boiler Supply or "hot" or "outlet" side
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