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AGE of WATER HEATERS
AIRBOUND HEAT SYSTEM REPAIRS
ALTERNATIVE HOT WATER SOURCES
ANODES & DIP TUBES on WATER HEATERS
ANTIFREEZE for BOILERS
ANTI SCALD VALVES
APPLIANCE EFFICIENCY RATINGS
AQUASTAT CONTROL Functions
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER VALVE, HEATING SYS
BACKFLOW PREVENTER, HEATER WATER FEEDER
BACKUP HEAT for HEAT PUMPS
CARBON MONOXIDE - CO
CHECK VALVES, WATER SUPPLY
CHEMICAL CONTAMINANTS in WATER
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CLOGGED DRAIN DIAGNOSIS & REPAIR
CLOGGED SUPPLY PIPING
CROSS CONNECTIONS, PLUMBING
DEBRIS in WATER SUPPLY, Water Heater
DRAIN a WATER HEATER TANK
ELECTRIC WATER HEATERS
FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
GALVANIC SCALE & METAL CORROSION
GAS BURNER Flame & Noise Defects
GAS FIRED WATER HEATERS
GAS PIPING, VALVES, CONTROLS
HEAT TAPES, Heat, Insulation prevent Freeze-Up
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS METHODS
HOT WATER SUPPLY
HOT WATER IMPROVEMENTS
HOT WATER DELIVERY SPEED UP
HOT WATER EFFICIENCY IMPROVEMENT
HOT WATER PRESSURE EXPANSION RATE
HOT WATER PRESSURE LOSS
HOT WATER PROBLEM DIAGNOSIS
HOT WATER QUANTITY IMPROVEMENT
HYDROGEN SULFIDE GAS
INDIRECT FIRED WATER HEATERS
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
NO HEAT - NO HOT WATER: HEATER DIAGNOSIS
NOISE / SOUND DIAGNOSIS & CURE
NOISE CONTROL for HEATING SYSTEMS
NOISE, PLUMBING CHECKLIST
NOISE, WATER HEATER
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER
PIPING IN buildings, Clogs Leaks Types
PLASTIC HEATER VENT
PLUMBING FIXTURES, KITCHEN, BATH
PLUMBING VENT DEFECTS & NOISES
PUMPS, HEAT PUMPS
PUMPS, OIL BURNER
PUMPS, PONY PUMPS
PUMPS, SEPTIC PUMPS
PUMPS, SEWAGE EJECTOR / GRINDER PUMPS
PUMPS, SUMP PUMPS
PUMPS, WATER PUMPS
PUMPS, WATER REPAIR
RELIEF VALVE LEAKS
RELIEF VALVES - TP Valves on Boilers
RELIEF VALVES - STEAM TP VALVES
RELIEF VALVES - Water Heaters
RELIEF VALVES - Water Tanks
SAFETY, HEATING INSPECTION
SCALE REMOVAL, WATER HEATERS
SEWER GAS ODORS
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
TANKLESS WATER HEATERS
THERMOSTATS, HEATING / COOLING
THERMOSTATS, WATER HEATER
TIMERS for ELECTRIC WATER HEATERS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER HEATER ALTERNATIVES
WATER HEATER ANODES, DIP TUBES
WATER HEATER AIR INLET
WATER HEATER DEBRIS FLUSH
WATER HEATER EFFICIENCY
WATER HEATER FLUSH PROCEDURE
WATER HEATER NOISES
WATER HEATER PROBLEM DIAGNOSIS
WATER HEATER PROPERTIES
WATER HEATER SCALE - De-Liming Procedure
WATER HEATER SCALE PREVENTION
WATER HEATER SAFETY
WATER HEATERS for HOME HEATING USE?
WATER ODORS, CAUSE CURE
WATER PIPES, Clogs Leaks Types
WATER PRESSURE & FLOW MEASUREMENT
WATER PRESSURE GAUGE ACCURACY
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PRESSURE REDUCER / REGULATOR
WATER PRESSURE PUMP REPAIR GUIDE
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER PUMP REPAIR GUIDE
WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER QUANTITY IMPROVEMENT
WATER SOFTENERS & CONDITIONERS
WINTERIZE A BUILDING
This article discusses when and how water heater tanks may be insulated, gives important water heater insulation safety warnings, and discusses whether you should insulate your water heater at all. This discussion is part of a series of articles on how to improve the hot water pressure, quantity, flow, and water temperature safety in a building.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
If your water tank is old, poorly insulated or if your water heater is not insulated at all, your plumbing supplier or building supply store can provide a water heater insulating blanket kit. See Range Boiler Water Heaters for an example of heaters that were commonly left completely uninsulated (when heating oil and gas were cheap). It can make sense to add insulation to such devices.
SAFETY WARNING: Do not add water heater insulation without reviewing both the safety warnings we list below and also any safety warnings issued by the manufacturer of your own water heater brand and model. Failure to follow safe procedures when insulating a water heater could result in a fire or explosion.
In our photos at page top and just above, the water heater blanket has been poorly installed. Above the insulation has been installed on an electric water heater, the relief valve is improperly installed, and other details about this particular insulating blanket installation suggest that it has not been installed following the recommendations of the water heater manufacturer. In the photo you can see that this valve is missing its discharge tube as well - an unsafe condition.
The warnings we issue below were suggested by Arlene Puentes and are based on a review of water heater instruction manuals from Rheem and AO Smith, two prominent manufacturers of residential water heaters.
Also see our advice and safety warnings about water piping insulation at Insulate Hot Water Piping.
The articles listed below offer more details about steps one can take to increase hot water quantity, pressure, and flow in a building. Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
How to improve hot water quantity and reduce water heating costs by installing an active pre-heating tank for domestic hot water supply
Install a water heater (oil, gas, solar, electric) on the water piping upstream, that is,a tank located before water enters the primary water heater such as the tankless water heater, tankless coil or even a conventional water heater (or primary water heating tank, whatever water heating method is used).
Passive hot water pre-heating tank operation reduces hot water production cost
This water tank can be left off when there is not much demand for hot water, in which case it will function as a passive water pre-warming tank as we discussed above.
Active hot water pre-heating tank for times of greater hot water demand
When a greater quantity of hot water is going to be needed (say many weekend visitors to a building), turn on the water heater to permit it to "boost" hot water headed for the tankless coil.
As occupants in the building draw hot water out of the system, heat will be drawn from the heating boiler and tankless coil at a very low rate, possibly not at all, until we've exhausted the hot water that was stored in the separate water heater tank.
Don't install the hot water pre-heater tank backwards
Some people install this system backwards: hot water is fed from the tankless coil into a water heater tank. This is a much less efficient way to make hot water as all of the water entering the water heater tank will always cause the heating boiler to run. We do not recommend this arrangement.
Frequently Asked Questions (FAQs)
Questions & answers or comments about how to insulate a hot water tank (or safety and warranty reasons not to insulate the water heater).
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.