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Troubleshooting Water Heaters

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Residential Electric Troubleshooting Table
Nature of Trouble:	Possible Cause:	What/How to Service:
No Hot Water	Manual switch turned off	Turn to ON
	Blown fuse at breaker	Replace or reset
	High limit switch tripped	Manually reset ECO button
	Upper thermostat defective	Check and replace
	Upper element defective	Check and replace
	Grounded thermostat	Check and replace
	Thermostat out of calibration	Check, tighten and replace
	Improper wiring Shorted or loose wiring Undersized service wire	Check and replace
Not Enough Hot Water	Thermostat set too low	Increase thermostat setting not to exceed 120 degrees
	Defective lower element	Check and replace
	Defective lower thermostat or miswired thermostat	Check and replace
	Improper wiring	Rewire per wiring diagram
	Loose wiring	Check and tighten
	Improper heating elements	Check wattage and replace
	Scale formation on heating element	Check elements; clean or replace
	Thermostat not flush with tank	Position thermostat so back touches the tank
	Poor grounding of tank	Check grounding and tighten
	Heater is undersized	Resize residence and compare
	Damaged dip tube	Check and replace
Water Too Hot	Thermostat setting too high	Lower thermostat setting
	Thermostat out of calibration	Check and replace
	Thermostat not flush with tank	Position thermostat so back touches the tank
	Grounded element	Check and replace
Slow hot Water	Heating elements too small	Check wattage and replace
Slow hot Water	Lower thermostat is defective	Check lower thermostat and replace
Noisy heating element	Scale build-up on elements	Remove, clean or replace
Noisy heating element	High watt density elements in the heater	Install low watt density elements
Excessive relief valve operation	Excessive water pressure	Install proper pressure reducing valve on cold side Check for open or closed system. Replace T&P valve and install thermal expansion tank.
Excessive relief valve operation	Excessive temperature	Check thermostat; lower setting or replace; check for grounded element.
Rusty or black water	Scale formation on elements	Clean or replace elements
	Anode rod dissolved	Check anode rod and replace
	Excessive sediment build-up	Try to drain tank; replace tank if sediment build up is excessive
Water heater is leaking	Cold in or hot out joints	Check joint and repair
	T&P valve	Check valve and replace Caution: Do not confuse normal T&P operation as a leaking tank. If the puddle dries up, then look for a T&P problem.
	Heating elements, anode rod and gaskets	Check, tighten and replace
	Inner tank has a pin hole	Replace water heater When diagnosing a leaker - you will notice a puddle of water on the floor, next to the heater, that will not go away.
Smelly water (rotten egg odor)	Bacteria formation inside water tank	Clean tank using chlorine bleach Replace anode rod if deteriorated Add automatic chlorine feeder to cold water inlet side of tank
Milky water	Aerated water	Allow a glass of hot water to set for a few minutes. If the water turns clear, the condition is a natural occurrence.

Residential Gas Troubleshooting Table
Nature of Trouble:	Possible Cause:	What/How to Service:
No Hot Water	Gas supply turned off	Turn on gas supply
No Hot Water	Pilot not lit	See Unable to light pilot and Pilot does not stay lit
Not Enough Hot Water	Thermostat set too low	Adjust thermostat
	Burner orifice is clogged	Inspect and clean
	Low gas pressure	Check gas supply pressure and manifold pressure
	Venting downdraft (or other improper draft)	Check for proper up draft venting. Check for other drafts that could blow out the pilot light.
	Clogged flue	Inspect and clean flue way
	Defective thermostat	Replace gas control valve
	Defective dip tube	Check and replace dip tube
	Heater is undersized	Adjust Peak Hour Demand
Unable to light pilot	Gas supply turned off	Turn on gas supply
	Gas cock knob dial not positioned correctly	Check lighting instructions. Set control knob
	Defective thermocouple	Check and replace thermocouple
	Defective safety magnet assembly	Check and replace gas valve
	Pilot burner orifice clogged	Clean or replace
	Pilot tube pinched or clogged	Clean, repair or replace
	Poor thermocouple connection	Check and tighten
	Air in gas line	Purge air from gas line
	Thermostat's single use ECO is tripped	Check ECO and replace gas valve
	Gas valve defective	Check gas valve
Pilot does not stay lit	Poor thermocouple connection	Tighten connection at gas valve
	Thermocouple defective	Check thermocouple and replace
	Thermocouple not in pilot flame	Move tip of thermocouple so it is immersed in pilot flame
	Defective safety magnet assembly	Check magnet and replace gas valve
	Venting downdraft (or other improper draft)	Check for proper up draft venting. Check for other drafts that could blow out the pilot light
	Clogged flue	Inspect and clean flue way
	Pilot partially clogged	Inspect and clean supply tube and pilot burner
	Improper gas pressure	Check and adjust supply side
Main burner will not stay lit	Low gas pressure	Check gas supply pressure
	Main burner orifice clogged	Clean or replace
	Main burner supply tube clogged or pinched	Clean, repair or replace
	Defective magnet assembly	Check and replace gas control valve
	Defective thermocouple	Check and replace
	Poor thermocouple connection	Inspect and tighten
	Defective main valve	Replace gas control valve
	Improper venting	Check venting for proper sizing and down drafts
Scale on burner and pilot assemblies	Condensation	Excessive condensation caused by undersized heater, poor venting or continued use
Scale on burner and pilot assemblies	Contaminated atmosphere	Check for contaminant causing chemicals near the heater
Sooting	Combustion air inlets or flueway is restricted	Remove obstruction or debris from heater or flueway
	Not enough combustion or ventilation air supplied to room	Improve combustion air or ventilation air supply
	Improper gas pressure	Check and adjust
	Burner orifice dirty	Inspect and clean
Yellow flame	Scale on top of burner	Shut off heater; allow to cool; clean burner plate
	Burner orifice dirty	Inspect and clean
	Flue way clogged	Inspect and clean
	Improper gas pressure	Check and adjust
Burner flame noisy (whistling)	Improper gas pressure	Check and adjust
Burner flame noisy (whistling)	Burner orifice dirty	Inspect and clean
Burner flame floats	Improper gas pressure	Check and adjust
	Wrong orifice	Install correct orifice
	Clogged flue	Inspect and clean flue way
Burner flame too high	Improper gas pressure	Check and adjust
Burner flame too high	Wrong orifice	Install correct orifice
Water too hot (follow by pilot outage)	Thermostat setting too high	Adjust thermostat to lower setting
Water too hot (follow by pilot outage)	Thermostat out of calibration	Check and replace thermostat
Slow hot water recovery	Burner orifice clogged	Check and clean
	Excessive drafts	Locate and eliminate drafts
	Clogged flue	Clean flue chamber
	Improper gas pressure	Check and adjust
Noisy water heater (rumbling and sizzling)	Scale or sediment build up in bottom of tank	Clean tank
	Baffles loose	Reset and tighten
	Condensation on main burner	Inspect for condensation (normal) and tank leaks
Excessive relief valve operation	Excessive water pressure	Install proper pressure reducing valve on cold side Check for open or closed system. Install expansion tank.
Excessive relief valve operation	Excessive temperature	Check thermostat; lower setting or replace
Rusty or black water	Anode rod dissolved	Check anode rod and replace
Rusty or black water	Excessive sediment build-up	Drain tank; replace tank if sediment build up is excessive
Water heater is leaking (Gas water heaters produce condensation that may drip on the floor. Condensation will produce only a few drips or small puddles that evaporate.)	Cold in or hot out joints	Check joint and repair
	T&P valve	Check valve and replace Caution: Do not confuse normal T&P operation as a leaking tank. If the puddle dries up, then look for a T&P problem.
	Immersion thermostat or anode rod is loose	Check, tighten and replace
	Inner tank has a pin hole	Replace water heater (When diagnosing a leaker – you will notice a puddle of water on the floor, next to the heater, that will not go away.)

Frequently Asked Questions

Q. "I see that you sell tankless instantaneous gas and electric water heaters. I even found that you sell large commercial as well as small undercounter water heaters but I do not see any regular residential water heaters. Have I missed them or don't you sell them?"
A.We do not sell "standard" water heaters because they are a product that is sold at home centers (many are priced near cost). When you add shipping costs (they are heavy and bulky), it simply doesn't make it feasible/practical/economical to sell them on the Internet. We are good at what we do, and we wish to be very competitively priced. With regular "standard" residential water heaters it simply isn't practical from our viewpoint.

Q. "What does 'Grounded Element' mean?"
A.A broken element that is possibly touching the inside of the tank completing the electrical circuit.

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