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AFUE DEFINITION, RATINGS
AGE of HEATERS, BOILERS, FURNACES
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER VALVE, HEATING SYS
BANGING HEATING PIPES RADIATORS
BOILER CONTROLS & SWITCHES
BOILER LEAKS CORROSION STAINS
BOILER NOISE SMOKE ODORS
BOILER OPERATING PROBLEMS
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
CHEMICAL TREATMENTS for BOILERS
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CIRCULATOR PUMPS & RELAYS
DEFINITION of HEATING & COOLING TERMS
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DRAFT MEASUREMENT, CHIMNEYS & FLUES
DRAFT REGULATORS, DAMPERS, BOOSTERS
FILTERS, OIL on HEATING EQUIPMENT
FIRE SAFETY CONTROLS
FLOODED HEATING EQUIPMENT REPAIR
FLUE VENT CONNECTORS
FREEZE-PROOF A BUILDING
FUEL OIL TYPES & CHARACTERISTICS
FUEL UNIT, HEATING OIL PUMPS
GAS BURNER Flame & Noise Defects
GAS PIPING, VALVES, CONTROLS
GAUGES ON HEATING EQUIPMENT
HEATING COST SAVINGS METHODS
HEATING LOSS DIAGNOSIS-BOILERS
HEATING OIL PIPING TROUBLES
HEATING SYSTEM INSPECTION GUIDE
HEATING SYSTEM NOISES
HIGH EFFICIENCY BOILERS/FURNACES
GAS LP & NATURAL GAS SAFETY HAZARDS
MANUALS & PARTS GUIDES - HVAC
MOTOR OVERLOAD RESET SWITCH
NO HEAT - BOILER
NOISE, HEATING SYSTEMS
ODORS FROM HEATING SYSTEMS
OIL PUMP FUEL UNIT
PUFFBACKS, OIL BURNER
RELIEF VALVES - STEAM TP VALVES
Reset Switch - Heater Primary Control
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY, HEATING INSPECTION
SAFETY RECALLS CHIMNEYS VENTS HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection S
STACK RELAY SWITCHES
STEAM HEATING SYSTEMS
THERMOSTATS, HEATING / COOLING
VIDEO GUIDES: Heating System Videos
ZONE VALVES, HEATING
Heating zone circulator pump bypass: how to circulate hot water in a hydronic heating system if the circulator or zone valve is not operable: bypassing the heating circulator pump or latching the zone valve open can get heat into the building even if the circulator pump itself is not working - maybe.
Our page top photo shows that a heating circulator pump motor has been removed completely while waiting for replacement. How can we get heat to flow in this building?
This article series describes how to diagnose & fix circulator pumps on hot water or hydronic heating systems.
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Can you continue to run the boiler if the circulating pump is not working properly? The house is heating but I'm concerned about how safe this is.
The pump tries to turn on but is not and i believe it may be the coupler and will have someone out to fix it but in the meantime; i just don't want to cause any more damage by keeping the heat on.. it's only 25 deg's today so i'm hoping it's not dangerous.
In general (which means we don't know a thing about your heating system so this may be wrong for you), heating boilers are controlled by one or more temperature-sensing devices - aquastats - as well as other safety controls. If a circulator pump is not working but the boiler is heating up, the boiler should not get hotter than the upper safety limit set by its HI LIMIT control.
Hot water will still circulate in some heating systems that use circulator pumps or even zone valves, even if the circulator pump is not working. Hot water will rise out of the boiler by convection and cooler water will return to the boiler's return side by the same process
In my photo at above left, push the metal lever all the way to the left then down to latch it in the "OPEN" Position.
See ZONE VALVES, HEATING for more details about diagnosing & fixing or replacing a bad zone valve.
The heating boiler flow control valves (photo at left) designed to prevent hot water circulating by convection when the circulator is not operating can also be manually placed in an OPEN Position.
See CHECK VALVES, HEATING SYSTEM for details.
The result is that heat will be delivered to the building by convection - more slowly than if the circulator were running - but still effectively.
In fact more than once I found this situation in homes that had hot water heat but no working circulator. The home would heat to a satisfactory temperature, but more slowly than occupants might have preferred.
This is also a stop-gap or backup method of keeping a building heated while waiting to replace or repair the circulator or circulator relay.
Watch out: in many but not all hot water heating systems that use a circulator pump, flow-control or flow-check valves and zone valves, you can get hot water to circulate by natural convection using the steps above. The thermostat calls for heat and provided that the boiler temperature is below the CUT IN setting on the boiler primaruy control or aquastat the boiler will cut-on, heating its water. Heated water will then rise in the heating distribution piping above the boiler and into the building.
Circulator Pump Diagnostic Q&A
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