American Water Heater 98 Gallon 80 Thermal Efficiency UltraLow NOx Heavy Duty Commercial Gas Water Heater User Manual

21
PERIODIC MAINTENANCE
VENTING SYSTEM INSPECTION
At	least	 once	a	 year	 a	visual	 inspection	 should	be 	made 	of	 the	 venting 	
system.	 You	should	look	for:
1. 		 Obstructions	 which	could	cause	 improper	 venting.	The 
	 combustion	and	ventilation	air	flow	must	not	be	obstructed.
2.		 Damage	 or	deterioration	 which	could	 cause	 improper	 venting 
	 or	leakage	of	combustion	products.
3.		 Rusted	flakes	around	top	of	water	heater.
Be	 sure	 the	vent	 piping	 is	properly	 connected	 to	prevent...

22
When	checking	 the	Temperature-Pressure	 Relief	Valve	operation,	
make	 sure	that	(1)	no	one	 is	in	 front	 of	or	 around	 the	outlet	 of	the	
Temperature-Pressure	 Relief	Valve	discharge	 line,	and	(2)	that	 the	
water	 discharge	 will	not	 cause	 any	property	 damage,	 as	the	 water	
may	 be	extremely	 hot.	Use	 care	 when	 operating	 valve	as	the	 valve	
may	be	hot.
To	 check 	the	 relief 	valve, 	lift 	the	 lever 	at 	the	 end	 of	valve	 several	 times,	
see	Figure	21.	 The	valve	should	seat...

23
Lime	accumulation	 not	only	 reduces	 the	life	of	the	 equipment	 but	
also	 reduces	 efficiency	 of	the	 heater	 and	increases	 fuel	consumption.
The	 usage	 of	water	 softening	 equipment	 greatly	reduces	 the	
hardness	 of	the	 water.	 However,	 this	equipment	 does	not	always	
remove	 all	of	the	 hardness	 (lime).	For	this	 reason	 it	is	 recommended 	
that	a	regular	schedule	for	deliming	be	maintained.
The	 time	 between	 cleaning	will	vary	 from	 weeks	 to	months	 depending 	
upon	water...

24
3. Close	cold	water	inlet	valve	to	heater.
4.  Connect	 hose	to	drain	 valve	 at	bottom	 of	heater	 and	start	
draining	heater	into	suitable	floor	drain	area.
5.  Remove	 relief	valve	 while	heater	 is	draining.	 NOTE:	Do	not	
replace	 relief	valve	 until	deliming	 is	completed.	 Relief	valve	
opening	 will	also	 act	as	a	vent	 in	case	 of	possible	 contact	
between	 the	delimer	 and	the	anode	 rod(s),	 which	may	produce 	
flammable	hydrogen-air	mixtures.
6.  If	relief	 valve	 appears	 to	be...

25
LEAKAGE CHECKPOINTS
A.	 Water	at	the	 draft	 hood	 is	water	 vapor	 which	 has	condensed	 out	
of	 the	 combustion 	products.		 This	is	caused	 by	a	problem	 in	the	
vent.	Contact	the	gas	utility.
B.		*Condensation	 may	be	seen	 on	pipes	 in	humid	 weather	 or	pipe	
connections	may	be	leaking.
C.		*The	anode	rod	fitting	may	be	leaking.
D.		Small	 amounts	of	water	 from	temperature-pressure	 relief	valve	
may	 be	due	 to	thermal	 expansion	 or	high	 water	 pressure	 in	your	
area.
E.		*The...

26
TROUBLESHOOTING GUIDELINES
These	guidelines	should	be	utilized	by	a	qualified	service	agent.
	 Problem Cause Solution
WATER LEAKSImproperly	sealed,	hot	or	cold	supply	connection,	relief	
valve,	drain	valve,	or	thermostat	threads.
Tighten	threaded	connections.
Leakage	from	other	appliances	or	water	lines. Inspect	other	appliances	near	water	heater.
Condensation	of	flue	products. Refer	to	CONDENSATION.
LEAKING T&P VALVE Thermal	expansion	in	closed	water	system.
Install	thermal	expansion	tank	(DO	NOT...

27
WATER PIPING DIAGRAMS
October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit www.hotwater.com.  AOSCG61130 | PAGE 1 of 1
  A. O. Smith Corporation reserves the right to make product changes or im\
provements without prior notice.NOTES:
1. Preferred piping diagram.
2.  The temperature and pressure relief valve setting shall not exceed press\
ure rating of any component in the system.
3.  Service valves are shown for servicing...

28October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit www.hotwater.com.  AOSCG61140 | PAGE 1 of 1
  A. O. Smith Corporation reserves the right to make product changes or im\
provements without prior notice.NOTES:
1. Preferred piping diagram.
2.  The temperature and pressure relief valve setting shall not exceed press\
ure rating of any component in the system.
3.  Service valves are shown for servicing unit. However, local codes...

29October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit www.hotwater.com.  AOSCG61150 | PAGE 1 of 1
  A. O. Smith Corporation reserves the right to make product changes or im\
provements without prior notice.NOTES:
1. Preferred piping diagram.
2.  The temperature and pressure relief valve setting shall not exceed press\
ure rating of any component in the system.
3.  Service valves are shown for servicing unit. However, local codes...

30October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visi t www.hotwater.com. AOSCG61160 | PAGE 1 of 1
  A. O. Smith Corporation reserves the right to make product changes or im\
provements without prior notice.NOTES:
1.  Preferred piping diagram.
2.  The temperature and pressure relief valve setting shall not exceed press\
ure rating of any component in the system.
3.  Service valves are shown for servicing unit. However, local...