A.O. Smith 101 Series, Instruction Manual

16

condensate drain

The  water  heaters  covered  in  this  manual  are  condensing 

appliances  and  require  a  building  drain  to  be  located  in  close 

proximity to allow the condensate to drain safely. 
Condensate drains from the water heater at the exhaust elbow 

located at the bottom. The field installed condensate drain line 

must  not  be  elevated  above  the  condensate  drain  connection 

on the condensate trap, see Figure 9.  if the condensate does 

not  drain  properly  it  will  build  up  in  the  exhaust  (vent)  elbow. 

This will restrict the flow of flue gases and cause the Blocked 

Exhaust pressure switch to open its contacts. The control system 

monitors  all  pressure  switches,  if  the  Blocked  Exhaust  Switch 

contacts are open the control system will lock out and disable 

heating  operation.  The  “Blocked  Exhaust”  Fault  message  will 

be displayed on the control system’s LCD, see Fault And Alert 

Conditions beginning on page 57.

note: 

if the “Blocked Exhaust “ Fault message is ever displayed 

on the control system LCD, check the condensate drain first and 

ensure it is not blocked.

CONDENSATE DRAIN

LINE - FIELD INSTALLED

CONDENSATE DRAIN

LINE CONNECTION

EXHAUST (VENT)

ELBOW

BUILDING

DRAIN

FACTORY INSTALLED

CONDENSATE TRAP

CLEANOUT

PLUG IS

REMOVED

TO CLEAR

DRAIN

figure 9

condensate drain water trap

Ensure a functioning water trap is

installed in the condensate drain.
Gas and carbon monoxide detectors

are available.
Install water heater in accordance with

the instruction manual.

Breathing carbon monoxide can cause brain damage or

death. Always read and understand instruction manual.

Breathing Hazard - Carbon Monoxide Gas

Do  not  remove  the  factory  installed  condensate  trap  for  any 

reason,  see  Figure  9.  The  water  heater’s  vent  pipe  is  under 

a  slight  positive  pressure.  The  water  trap  prevents  flue  gases 

from escaping into the installed space. See Condensate Drain 

Installation on page 36.

condensate ph leVel

The  condensate  drains  from  the  water  heater’s  covered  in 

this  manual  have  PH  levels  between  4.3  and  5.0.  install  a 

commercially available neutralizing kit if required by local codes.

note:

 Lower PH levels are acidic. Do not connect a metal drain 

line,  such  as  copper,  to  the  water  heater  for  this  reason.  See 

Condensate Drain installation on page 36.

comBustiBle material storage

Fire or Explosion Hazard

Read instruction manual before

installing, using or servicing

water heater.

Avoid all ignition sources if you smell gas.

Do not store or use gasoline or other flammable vapors and

liquids in the vicinity of this or any other appliance.

Use only the gas shown on the water heater rating label.

Keep ignition sources away from faucets after extended

periods of non-use.

Maintain required clearances to combustibles.

Do not expose water heater controls to excessive gas

pressure.

keep  appliance  area  clear  and  free  of  combustible  materials, 

gasoline and other flammable vapors and liquids.

contaminated air

Breathing Hazard - Carbon Monoxide Gas

Install water heater in accordance with

the Instruction Manual and NFPA 54 or

CAN/CSA-B149.1.
To avoid injury, combustion and ventilation

air must be taken from outdoors.
Do not place chemical vapor  emitting

products near water heater.

Breathing carbon monoxide can cause brain damage or

death. Always read and understand instruction manual.

Corrosion of the flue ways and vent system may occur if air for 

combustion  contains  certain  chemical  vapors.  Such  corrosion 

may result in failure and risk of asphyxiation.
Combustion  air  that  is  contaminated  can  greatly  diminish  the 

life  span  of  the  water  heater  and  water  heater  components 

such as hot surface igniters and burners. Propellants of aerosol 

sprays,  beauty  shop  supplies,  water  softener  chemicals  and 

chemicals used in dry cleaning processes that are present in the 

combustion, ventilation or ambient air can cause such damage.
Do not store products of this sort near the water heater. Air which 

is brought in contact with the water heater should not contain any 

of these chemicals. if necessary, uncontaminated air should be 

obtained from remote or outdoor sources. The limited warranty 

is  voided  when  failure  of  water  heater  is  due  to  a  corrosive 

atmosphere.  (See  limited  warranty  for  complete  terms  and 

conditions).
if the water heater will be used in beauty shops, barber shops, 

cleaning  establishments,  or  self-service  laundries  with  dry 

cleaning equipment, it is imperative that the water heater(s) be 

installed in a Direct Vent configuration so that all air for combustion 

is derived directly from the outdoor atmosphere through a sealed 

intake air pipe. See Venting Installation on page 21.