Domestic Hot Water Tanks Flashcards
(20 cards)
What is a domestic hot water tank used for
To heat and store water for use, the water with the help of a thermostat is controlled at a temperature of 140 degrees f
A HWT is tested to _____PSI to withstand a safe working pressure
300
The incoming cold water should always feed to the ______
Bottom of the tank to prevent mixing of hot and cold water
To prevent damage to the dip tube the copper solder connection should be made ______ the threaded connection to the HWT is made
Before
The dip tube is drilled at the ____\ of it to make an ______
Top
Anti siphon hole
Every water service pipe shall be sized according to the _______ but shall not be less than ____ in size
Peak demand flow
3/4inch
Every water pipe that supplies a hwt shall be provided with a _____ located on the
Shut off valve
Cold side
Hot water tanks are made of ____ and ____ lined
_____ lined
_______
______ coated
And on larger tanks they may be ____ lined
Steel
Epoxy
Glass
Galvanized
Zinc
Cement
To reduce corrosion over time due to electrical and chemical effects of heating water, a ________ known as a “_________ _______” is installed. This rod will corrode before the tank does therefore minimizing costly repairs
Magnesium rod
Sacrificial anode
Most common types of hwt’s include the use of either ____ or ___ and in some older applications ____ was used
Gas
Electric
Oil
Why are gas HWT’s ideal
Faster recovery
Lower cost to operate
Required burn gases to be exhausted
May have an internal or external flue arrangement
2 types of electric
Strap on element - electrically heated metal band that is installed outside and around the inner HWT
Immersion element- electric coil like device that’s installed in the HWT in direct contact with the water
Tankless water heaters are also known as
Demand type or instantaneous water heaters
What do tankless water heaters do
Provide hot water only as needed = Less energy losses
Tankless water heaters heat water directly ____ the use of a ______
Without
Storage tank
Tankless water heaters heat provide hot water at a rate of
2-5GPM
What can you do when hot water supply is not enough for simultaenous uses
Installing separate tankless water heaters for clothes washers or dishwashers
Other applications for demand water heaters include
Remote bathrooms and hot tubs
Booster for appliances like dishwashers/clothes washers
Booster for solar water heating systems
When selecting the right tankless water heater you should consider
Size of unit
Fuel or operating type (electric/gas)
Energy efficiency
Costs
Always •
Request costs estimates in writing
Ask for references
Check company with BBB
see if company will get a local permit if necessary and understands local building code
