Water Heaters Flashcards
What are two types of water heaters and 2 energy sources
Pilot and DSI.
Propane and 120AC
What are the most common sizes of water heaters
6 and 10 gallon
Why would a pilot model water heater need 12V?
To supply the optional reignitor
Where does the primary and secondary air enter for the flame?
Primary from the air shutters and secondary at the end of the burner tube
What are the two types of water tanks?
And which one needs an anode rod?
Zinc clad aluminum
Glass lined steel
Glass lined tanks need anode rods
What kind of glue tube does the glass lined steel tank have?
The flue tube is a large closed-end pipe with a horizontal divider plate. Goes to the back, then up, then out
How many watts are the heating elements
1000-1500 watts
What is in the 120v heating element circuit?
Switch
T-stat
ECO
Heating element
What is the ECO set at?
180F
What is the T-stat set at?
And what temp does it usually kick back on at?
140f
100f
What happens when the ECO trips on a pilot model water heater?
Will need to replace the whole gas valve
What is an XT water heater?
It’s a 10g water heater that heats the water to 170F and has a mixing valve on the back. Advertised as a 16 gallon tank
What temp and pressure is the T&P valve set at?
150psi and 210F
What is the purpose of the T&P valve?
To protect the water heater from rupturing if both the T-stat and the ECO fail
What size connection is at the water connections?
1/2 female pipe thread
What determines the water heat with the engine assist?
The engine coolant temp
Can overheat the ECO
What happens inside the tank when the water is being heated?
Electrolysis. Which will eat away at the tank lining and anode rod
When should the anode rod be replaced?
When there’s 75% gone
What does the thermocouple produce
When unloaded?
When loaded?
25-35 millivolts unloaded
12-14 millivolts loaded
On a DSI water heater, how much power does the board sent through the flame sense?
1.5 micro Amps
Explain the dielectric strength test
A test that the circuit is capable of withstanding 900v for 1 min
Or 1080 v for 1 sec
Is you use DC power us 1.414 times the value
What should the gas valve read when testing it?
45 ohms
What is the switch normally on a water heater?
Usually a rocker switch with and indicator light. Has 4 spade connectors on the back
Where is the thermostat normally located?
Usually mounting on the front or back of the tank
What does ECO Stand for?
Energy cutoff switch
What colour wire goes to the LED bulb?
Blue
What is the advantage of a potted board?
It’s resistant to corrosion and damage
What power is sent to the board how long does it wait before sparking?
6-8 second
When testing the flame sense, what should you use to protect your meter?
A 1.5microfarad capacitor in parallel
What is the difference between a pilot and DSI water heater?
12 volts and a switch
What is the advantage of a instant hot water tank?
More efficient because water is not stored?
How much water much be flowing to open the impeller switch?
1.4 gallons per minute
What line is used on the instant water heaters and how is the temperature monitored?
Copper coils is used for good heat transfer. And has thermal switches at the bottom middle and top
What size can do the instant water heaters go up too
50,000 btu’s/hr
What size inlet water supply is needed for the instant water heater
1/2”
How much water is left in the water heater after it’s drained?
About 2 litres
What can be used to clean and sanitize and remove odour from the tank?
A solution with 0.5% chlorine
What is the main cause of the p&t valve leaking?
A depletion of the air pocket
Oh a cooktop what should be installed in the burner tubes to keep them from rattling?
A neoprene sleeve
Where are the regulators mounted on the cooktops?
They are mounted to the manifold inlet
On the cooktops, what is the pilot flame adjustment size?
1/8”
On the cooktops what are the tubes called that’s allow the one pilot to light multiple burners?
Zip tubes or flash tubes
What determines the maximum volume of gas to the burner?
The orfice
How should you clean the cooktop burners?
Soak in warm water and clean with a toothpick
What is a RV range?
A cooktop and an oven
P&T valve thread sizes are?
1/2” or 3/4” national pipe thread
