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AIR FILTERS for HVAC SYSTEMS
AIRBOUND HEAT SYSTEM REPAIR by WATER FEED VALVE
ANODES & DIP TUBES on WATER HEATERS
ANTIFREEZE for BOILERS
ANTI SCALD VALVES
APPLIANCE DIAGNOSIS & REPAIR
APPLIANCE EFFICIENCY RATINGS
ASBESTOS IDENTIFICATION IN buildings
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER VALVE, HEATING SYS
BACKFLOW PREVENTER, HEATER WATER FEEDER
BACKUP HEAT for HEAT PUMPS
BANGING HEATING PIPES RADIATORS
BIOGAS PRODUCTION & USE
BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
BLUE vs YELLOW COMBUSTION FLAMES
BOILER CHEMICAL TREATMENTS
BOILER COMPONENTS & PARTS
BOILER CONTROLS & SWITCHES
BOILER LEAKS CORROSION STAINS
BOILER LEAKS, HOW TO LOCATE
BOILER NOISE SMOKE ODORS
BOILER OPERATING PROBLEMS
BOILER OPERATING STEPS
BOILER PRESSURE & TEMPERATURE SETTINGS
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
BUILDING SAFETY HAZARDS GUIDE
CAPACITORS for HARD STARTING MOTORS
CARBON DIOXIDE - CO2
CARBON MONOXIDE - CO
CHEMICAL TREATMENTS for BOILERS
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CHIMNEYS & Flues - Asbestos Transite Pipe
CHINESE DRYWALL HAZARDS
CIRCULATOR PUMPS & RELAYS
COOL OFF HEAT, Thermostat Switch
COMBUSTION AIR for TIGHT buildings
COMBUSTION GASES & PARTICLE HAZARDS
COMBUSTION PRODUCTS & IAQ
COMPLETE COMBUSTION, Stoichiometric
CREOSOTE FIRE HAZARDS
Curved Brick Chimneys - Sulphation
CONDENSING BOILERS/FURNACES DAMAGE
CONVECTOR HEATERS - HYDRONIC COILS
DEFINITION of HEATING & COOLING TERMS
DIAGNOSTIC GUIDES A/C / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DIRECTORY of OIL TANK EXPERTS
DRAFT HOODS - gas fired
DRAFT MEASUREMENT, CHIMNEYS & FLUES
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS
DUST, HVAC CONTAMINATION STUDY
DUST SAMPLING PROCEDURE
ELECTRIC MOTOR DIAGNOSTIC GUIDE
ELECTRIC MOTOR OVERLOAD RESET SWITCH
ELECTRICAL POWER SWITCH FOR HEAT
FAN, AIR HANDLER BLOWER UNIT
FAN AUTO ON Thermostat Switch
FAN, COMPRESSOR/CONDENSER UNIT
FAN CONVECTOR HEATERS - HYDRONIC COILS
FAN LIMIT SWITCH
FILTERS, AIR for HVAC SYSTEMS
FILTERS, OIL on HEATING EQUIPMENT
FIRE SAFETY CONTROLS
FIREPLACES & HEARTHS
FLAME COLOR, BLUE vs YELLOW COMBUSTION
FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
FLUE SIZE SPECIFICATIONS
FLUE VENT CONNECTORS
FREEZE-PROOF A BUILDING
FUEL OIL TYPES & CHARACTERISTICS
FUEL UNIT, HEATING OIL PUMPS
FURNACE CONTROLS & SWITCHES
FURNACE EFFICIENCY, HIGH vs MID
FURNACE HEAT EXCHANGER LEAKS
FURNACE OPERATION DETAILS
FURNACE OPERATING TEMPERATURES
GALVANIC SCALE & METAL CORROSION
GAS BURNER Flame & Noise Defects
GAS FIRED WATER HEATERS
GAS PIPING, VALVES, CONTROLS
GAUGES ON HEATING EQUIPMENT
GEOTHERMAL HEATING SYSTEMS
HEAT EXCHANGER LEAK TEST
HEAT LOSS in BUILDINGS
HEAT LOSS DETECTION TOOLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HEAT PUMPS, DIAGNOSIS, REPAIR
HEAT TAPES & CABLES on Roofs for Ice Dams
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS METHODS
HEATING LOSS DIAGNOSIS-BOILERS
HEATING LOSS DIAGNOSIS-FURNACES
HEATING OIL CLOUD WAX GEL POINT
HEATING OIL EXPOSURE HAZARDS, LIMITS
HEATING OIL - OLD, USEABLE?
HEATING OIL PIPING TROUBLES
HEATING OIL SHELF LIFE
HEATING OIL SLUDGE
HEATING OIL USAGE RATE
HEATING SYSTEM INSPECT DIAGNOSE REPAIR
HEATING SYSTEM INSPECTION DETAILS
HIGH EFFICIENCY BOILERS/FURNACES
HOT WATER HEATERS
HOT WATER IMPROVEMENT
INSULATION INSPECTION & IMPROVEMENT
LOW VOLTAGE BUILDING WIRING
LOW VOLTAGE TRANSFORMER TEST
GAS LP & NATURAL GAS SAFETY HAZARDS
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH
NATURAL GAS COMBUSTION PRODUCTS
NO HEAT - BOILER
NO HEAT - FURNACE
NOISE / SOUND DIAGNOSIS & CURE
NOISE AIR CONDITIONER / HEAT PUMP
NOISE, DUCT VIBRATION DAMPENERS
NOISE, HEATING SYSTEMS
NOISE, WATER HEATER
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS FROM HEATING SYSTEMS
OIL BURNER FUEL UNIT
OIL BURNER INSPECTION & REPAIR
OIL BURNER NOISE SMOKE ODORS
OIL BURNER NOZZLE & ELECTRODES
OIL BURNERS, RETENTION HEAD
OIL BURNER SOOT & PUFFBACKS
OIL FILTERS on HEATING EQUIPMENT
OIL FILTER MISSING
OIL FUEL TYPES & CHARACTERISTICS
OIL HEAT FIRE SAFETY CONTROLS
OIL LINE CLOGGING FIX
OIL LINE QUICK STOP VALVES
OIL LINE SAFETY VALVES, OSVs
OIL FILL PIPE LEAKS
OIL PUMP FUEL UNIT
OIL SPILL CLEANUP / PREVENTION
PLASTIC Plexvent / Ultravent RECALL
PULSE COMBUSTION HEATERS
PRESSURE REDUCING VALVES
PRESSURE REGULATOR, WATER
PUFFBACKS, OIL BURNER
PUMPS, PONY PUMPS
RADIANT HEAT Floor Mistakes to Avoid
RADIANT HEAT TEMPERATURES
RADIANT SLAB FLOORING CHOICES
RADIANT SLAB TUBING & FLUID CHOICES
REFRIGERANTS & PIPING
RELIEF VALVE LEAKS
RELIEF VALVES - TP Valves on Boilers
RELIEF VALVES - STEAM TP VALVES
RELIEF VALVES - Water Heaters
RELIEF VALVES - Water Tanks
Reset Switch - Heater Primary Control
Reset Switch Broken - Quick Repair
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY HAZARDS & INSPECTIONS
SAFETY HAZARDS GUIDE
SAFETY, HEATING INSPECTION
SAFETY RECALLS CHIMNEYS VENTS HEATERS
SOLAR HEATING SYSTEM DESIGNS
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS
STACK RELAY SWITCHES
STAIN DIAGNOSIS on BUILDING INTERIORS
STEAM HEATING SYSTEMS
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
THERMAL TRACKING & HEAT LOSS
THERMOSTATS, HEATING / COOLING
THERMOSTATIC EXPANSION VALVES
Transite Pipes, Chimneys & Flues
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
ZONE VALVES, HEATING
How to inspect and diagnose heating system condition: This heating system inspection article and other articles at this website explain Heating System Inspection Concepts - how to prepare for and control the heating system inspection process to assure that the inspection is complete and accurate. We describe how to inspect, troubleshoot and repair heating and air conditioning systems to inform home owners, buyers, and home inspectors of common heating system defects. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
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How to Inspect Heating Systems - Example of An Approach to the Forensic Inspection of Any Complex System
This document presents a detailed methodology for inspecting, diagnosing, & repairing defects on residential heating systems with attention to inspection methods selected to assure completeness, accuracy, and the maximum level of defect detection. The heating system inspection methodology described here serves as a guide to the forensic diagnostic inspection of any complex system where the highest probability of detecting important safety or operating defects is important.We describe organized procedures for inspecting complex systems for defects, without losing the ability to discover unexpected problems as well.
© Copyright Daniel Friedman 2012 - 1993 all rights reserved -- Tri-State ASHI Home Inspection Education Seminar - Initial Presentation November 6-7, 1993 -- Last update 08/03/2012
This presentation follows a procedure for inspecting, using heating system operating sequence as a method to assure that all important system components are considered. A version of the ASHI Standards of Home Inspection Practice (readers should check most recent Standards version for changes) is mapped into this heating system inspection procedure but does not guide the actual inspection sequence. The organization of home inspection standards is not intended as a guide to an inspection sequence nor as a guide to heating system inspection reports. Home Inspection Standards requirements during the inspection of a home heating system are identified in italics in the text below.
HEATING INSPECTION CONCEPTS - How to Select an Inspection Methodology for Heating System Inspection & Diagnosis
In order to be as thorough, accurate, and safe as possible, a heating system inspector should use a well-defined order of discovery which assures that s/he examines all important heating system components. Several possible heating system inspection "road maps" can be used for this purpose. Two approaches inspect the heating equipment by physical layout of components, or by inspecting the heating system in the detailed order that it will operate during the heating system operating cycle.
Of these "heating system inspection road maps", the first of these inspection methods is physically convenient, that is: inspect each heating system component where each is located in each building area, and this is the most common approach in use in the field. But but it is the second option, heating boiler or furnace operating sequence, that best assures that the inspector considers proper system operation and that s/he identifies all of the system components.
Thinking thorough the sequence of steps in operation of a home heating system requires that the inspector understand how heating systems work. An inspector who cannot follow this sequence does not understand heating system operation and is rather likely to miss important system defects.
So how should a heating system be inspected? For efficiency the inspector may decide to examine each system component as s/he enters the area of the building where that component resides. So all heater components in the basement or crawl space are examined in one pass while the inspector is in that area, and so on.
But in thinking about the completeness and accuracy of the heating system check the inspector should also think through the system's operating sequence, using the components identified in that sequence to assure that s/he has not omitted something important. Why is this second thought pattern needed? Because it is always easier to inspect and think about a building component that we see than to think about a component that is simply absent. In other words, if there is no temperature or pressure relief valve to see on a boiler, the inspector may fail to think about whether or not this is a serious safety hazard for the particular installation.
This approach broadens the scope of the heating system inspection and it may aid in heating system defect recognition or problem diagnosis, for example by observing that a heating boiler is located in a small, air-tight room (possible combustion air problems), or that the furnace is quite close to the oil storage tank.
This approach to heating system inspection Identifies most components of heating systems or of other mechanical systems and is most likely to give the most complete list system parts. It helps assure that all critical components are considered. Actual observation of heating system operation is important in enabling the inspector to identify malfunctions. The heating boiler or furnace inspector's field procedure should include this aid.
A detailed example of the steps in the sequence of operation of a heating system along with a detailed list of heating system components is provided below at Sample Inspection Procedure for Heating Equipment.
A superficial heating system inspection may simply identify the type of system present and perhaps the presence of obvious visual anomalies such as leaks. But an astute inspector understands more thoroughly the implications for safety or function of the defects that s/he observes and thus is more likely to inspect the heating system more thoroughly and is more likely to report the inspection findings in a meaningful way to the client.
It is essential that a heating system inspector clearly communicate to the client the significance of the inspection results. In other words, the client should be given to understand the need for action, or urgent action, the presence of unsafe conditions, or the indications that costly repairs or replacement are likely to be needed immediately or in the coming year or before next heating season.
Here are two examples of the difference between simply reporting a home inspection observation neutrally and thinking about the significance of a home inspection observation in a way that might lead to discovery of something important about a heating system.
Example Outdoor Inspection Observation: drip lines below roof eaves
Observation: The heating system inspector, before entering the home, observes outside that there are
deep drip lines in the soil below the home's roof eaves. Drip lines indicate that there has been long term poor control of roof runoff.
Outside we observed roof overflow or drip lines below the house eaves.
Inside, A BrandX natural-gas fired 90,000 BTUH steel hot air furnace heating system is installed. The system appears to be 20 years old. In response to turning up the heat we observed that the system operated normally: heat came out of the air supply registers. (Our inspection excludes heating system disassembly and therefore cannot examine the condition of the furnace interior components. You should have the system inspected by a qualified technician.
Outside we observed roof overflow or drip lines below the house eaves. This means that water has been spilling by the house foundation for a long time, that roof gutters and downspouts are needed, and that the home may have been exposed to a history of water entry or leaks which in turn could cause problems indoors.
Inside, A BrandX natural-gas fired 90,000 BTUH steel hot air furnace heating system is installed. The system appears to be 20 years old and based on age alone is likely to be at or near the end of its useful life - significant expense will be involved when furnace replacement is needed.
In response to turning up the heat we observed that the system operated normally: heat came out of the air supply registers. Our inspection excludes heating system disassembly and therefore cannot examine the condition of the furnace interior components.
However, we observed heavy rust on the bottom of the furnace and other evidence of a history of water entry in the basement. A furnace exposed to these conditions is at extra risk of hidden rust damage such which could include a leaky heat exchanger. If the heat exchanger is leaking this heating system would be unsafe, should not be used, and would almost certainly require immediate replacement - a significant expense.
We recommend that before completing purchase of the home, and certainly before using the system in the coming heating system, you should have the furnace inspected and tested by a qualified technician, and you should specifically ask the technician to make a thorough inspection and test of the furnace heat exchanger for leaks and safety.
Addressing the question of completeness of coverage of components, for a thought-guide to inspecting heating equipment we selected Sequence of Operation as a model.
It is the possible significance of a home inspection observation that leads a good inspector to examine the property further for confirmation or refutation of the presence of a possibly serious building defect. We discuss this concept of thinking carefully about and pursuing possible implications of home inspection observations as a way to assure that an inspection is thorough and as a means to minimize the chances of missing an important condition at a property, in these articles:
When inspecting heating systems, while a dramatic and obvious visual clue such as severe rust on a furnace may catch our attention (beware of attention capture errors which make you miss something else), we usually start with broad views, examine further with detailed views, and again make final checks with a broad view.
For home inspections in general because many building systems and conditions affect one another (no gutters, wet basement, rusted furnace, dangerous conditions), a broad view is appropriate for most topics, even where a detailed examination is always made.
Here we explain how to prepare for and control the inspection process.
When inspecting any building or building component the inspector should generally proceed in this simple order: Look, Think, Understand/Speculate-wait, Write, Speak. We've found that if we start talking too soon we often have to change our mind about the importance of what we've seen as further inspection and new clues produce more data. We've found that if we start talking before we've written down our observations, there is a real risk that our final notes and report may be incomplete and may not coincide perfectly with what we said to the client during the inspection. Any substantive differences in observations or conclusions between the onsite oral report and the written inspection report are an invitation to misunderstanding or worse.
Prior education & experience of the inspector: a good heating system inspector prepares by knowledge (education and experience) and attitude (for whom ins the inspector working and how diligent is the inspector going to be?). An inspector who schedules many inspections in a given day is unlikely to have the time nor the ability to attend to those details that make for a competent and responsible job.
On arriving at a building inspection in preparation for inspection of the heating system or any other building or building system or component here are some steps that aid in assuring that the inspector's attention will be fully focused on the job at hand:
How to pay close attention for hours at a time: without the audible use of Zen mantras or other eyebrow-raising behavior the inspector must be calm, relaxed, and completely focused on the process of inspection.
How to avoid heating system errors and omissions:
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