Lochinvar CG200 User Manual

23

If initial inspection after 6 months shows 2” of lime accumulation.

Therefore, the heater should be delimed every 3 months.

Hydrochloric base acids are not recommended for use on glass 

lined tanks.

The following practices will ensure longer life and enable the unit 

to operate at its designed efficiency:

1.  Once a month the heater should be flushed. Open drain valve 

and allow two gallons of water to drain from the heater. Inlet water 

valve should remain open to maintain pressure in tank.

2.  A cleanout opening is provided for periodic cleaning of the tank. 

Gas must be shut off and heater drained before opening cleanout.

To clean heater through cleanout opening, proceed as follows:

1.  Drain heater.

2.  Remove outer cover plate from lower side of heater jacket.

3.  Remove six (6) hex head screws securing tank cleanout plate 

and remove plate.

4.  Remove lime, scale, or sediment using care not to damage the 

glass lining.

5.  Inspect cleanout plate gasket, if new gasket is required, replace 

with part no. 9004099215.

6.  Install  cleanout  plate.    Be  sure  to  draw  plate  up  tight  by 

tightening screws securely.

7.  Replace outer jacket cover plate. 

In some water areas the sediment might not be removed by this 

method and may result in the water heater making rumbling or 

boiling noises.

Before calling your service agent, the following checklist should 

be examined to eliminate obvious problems from those requiring 

replacement or servicing.

— Check that “main manual gas shutoff valve” is fully open and 

that gas service has not been interrupted.

— Check  that  after  following  the  appliance  OPERATING 

INSTRUCTIONS, the “Top Knob” of the appliance gas valve 

is in “ON” position.

— Check electrical supply to the appliance for possible blown (or 

tripped) fusing or power interruption.

— Is  the  water  temperature  in  tank  below  the  thermostat  dial 

setting on the appliance thermostat (calling for heat)?

— It is possible that the high limit (E.C.O.) has functioned to shut 

off  the  appliance.    See  FEATURES  —  Water Temperature 

Control for reset procedure.  Contact your serviceman if limit 

continues to function to shut off appliance. 

Your  water  heater  is  equipped  with  an  ignition  module  that 

incorporates  a  diagnostic  system  to  assist  in  troubleshooting 

the appliance.  The indicator codes on the ignition module are 

as follows:

 System lockout (retries or cycles exceeded)

Pressure switch stuck close

Pressure switch stuck open

Open on high temperature limit switch (eco)

115 volt AC power reversed (check polarity)

Low  flame  sense  signal  (make  sure  flame 

sensor is in burner flame)

Check ignitor

continuous flash -> continuous flame sensed > 5 seconds without 

gas valve

continuous on -> internal control failure - replace ignition control 

module.

Use this diagnostic system in conjunction with the “OPERATIONAL 

CHECKLIST”  and  the  “SEQUENCE  OF  OPERATION”  to 

troubleshoot the appliance.