American Water Heater High Efficiency Commercial Gas HCG Series AHCG3 119T 300 THRU AHCG3 119T 500 Series 200 201 User Manual

51
SERVICE CONTACT INFORMATION
The control system has a discrete menu that Installing contractors and/or service agents can access to enter contact information for 
their customers. This contact information will be displayed with all Fault and Alert messages.
DESCRIPTION/ACTIONDISPLAY
From  the  Desktop  Screen  (see  Figure  52  on  page  44)  press 
and hold down the middle (unmarked) Operational Button for 30 
seconds and then release it.
This  will  launch  a  discrete  menu  where  personalized...

52
PRIOR TO START UP
Installation  and  start  up  of  this  water  heater  requires  abilities 
and  skills  equivalent  to  that  of  a  licensed  tradesman  in  the  field 
involved, see Qualifications on page 6.
Do  not  place  the  water  heater  in  operation  if  any  part  has  been 
under  water.  Immediately  call  a  qualified  service  technician  to 
inspect  the  water  heater  and  to  replace  any  part  of  the  control 
system and any gas control which has been under water. 
Light  the...

53
LIGHTING & OPERATION LABEL
The instruction label below is affixed to the water heater's covered by this manual at the factory and must be followed when lighting 
and operating the water heater.
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.  Set the Enable/Disable switch on the control panel
      to the Enable position.
4.  Set the Enable/Disable switch on the control panel
      to the Disable position.
8....

54
Gas Line Installation on page 39 and Supply Gas Regulator on 
page 13. Ensure all requirements and installation instructions 
are maintained.
CHECKING THE FIRING RATE
If  firing  rate  adjustment  is  required  follow  these  instructions  to 
determine the actual firing rate of the water heater:
NOTE:  The  heaters  covered  by  this  manual  are  capable  of 
modulating  their  firing  rate.  The  firing  rate  should  be  checked 
with the heater operating at it's full firing rate.
1. Ensure...

55
HIGH ALTITUDE INSTALLATIONS
Fire and Explosion Hazard
Gas and carbon monoxide detectors ar e
available.
Overfiring could result in fire or
explosion. Under no circumstances should the 
input exceed the rate shown on the 
water heater ’s rating label.  
Breathing Hazard - Carbon Monoxide Ga s
Breathing carbon  monoxide can cause brain  damage or
death.  Always read and understand  instruction  manual. Under no circumstances should
the input exceed the rate shown
on the water heater
’s rating label....

56
SEQUENCE OF OPERATION
Read  the  Sequence  of  Operation  below  before  attempting  to 
correct  any  operational  problems.  Refer  to  the  Features  And 
Components  section  beginning  on  page  7  for  the  location  of 
various  water  heater  components  described  below.  See  the 
Sequence Of Operation Flow Chart on page 57 also.
1. When the control system is first powered, during boot 
up,  it  will  display  water  heater  model  information 
during  initialization. After  a  few  moments...

57
SEQUENCE OF OPERATION FLOW CHART
YESNO
Water is  h eat ed to 
se t poin t24 VAC  Ga s Va lve
de -energi zed
Inter-Pu rge  cycl e24 VAC  Ga s Va lve
de- energ ized
Re trie s  up  to
tw o mo re time sPost-P urge  cycl e
Cont rol S yst em  
Loc ks Out
“I gni tion  Failure”  
Fa ult Ms g is 
di sp laye d
Wa ter heat er goes  
in to  sta ndby  mode
If ta nk te mp erat ure drop s bel ow Oper ating  Se t Po int mi nus 
Di fferen tial  se tting  a heati ng cycle  is  ac tiva ted
Bl ow er Prov er  sw itch  co...

58
requirements (erratic gas supply volume/pressures) - see 
Supply Gas Regulator on page 13.
•  Excessive supply gas pressure - see Table 4 on page 10 
and Supply Gas Pressure Adjustment on page 54.
•  Vent (exhaust) gas recirculation at the vent and intake air 
pipe terminations on Direct Vent installations - see Direct 
Vent Installation on page 23.
•  Excessive equivalent lengths of intake air and/or vent 
(exhaust) piping installed - see Venting Requirements on 
page 22.
•  Debris clogging/blocking...

59
ALERT CONDITIONS
When the control system declares an Alert condition it will display 
an Alert message on the control system's LCD with a question "?" 
mark.  The  water  heater  will  continue  to  operate  during  an Alert 
condition  but  the  water  heater  must  be  serviced  by  a  qualified 
service agent as soon as possible.
RESETTING CONTROL SYSTEM LOCK OUTS
To  reset  the  control  system  from  a  lock  out  condition;  turn  the 
electrical power supply off for approximately 20...

60
FAULT AND ALERT MESSAGES
Call the technical support phone number listed on the back cover for further technical assistance or to locate a qualified service agent 
in your area.
POSSIBLE CAUSES - CHECK/REPAIRDISPLAYED FAULT/ALERT MESSAGE
• Using a manometer, ensure that gas supply pressure is above 
minimum requirement listed on heater’s data plate and does not 
drop more than 1.5” W.C.   when unit fires.
•  Ensure wire connections to gas valve are clean and tight.
•  Ensure wire connections to flame...