Checkout - A.O. Smith 160M Operation Manual

REMOVING SILICATE
Ammonium bifluoride flakes (NH
with A. O. Smith UN•LIME delimer and pump type deliming kit,
part no. 4930, to delime and remove siliceous materials from
copper coil water heaters.

CHECKOUT

The checkout sequence should be used as an on-the-job trouble-
shooting guide to identify the cause of incorrect system operation
and suggest a remedy for its correction.
Because improper piping and wiring can result in unsatisfactory
system performance, it is suggested that the installation be
CHART 1 - CER-TEMP 80 RECOVERY SYSTEM CHECKOUT PROCEDURE
Checkout Sequence
Set tank temperature
control 20° (11°C) below
tank water temperature
Set tank temperature
control 20° (11°C) above
tank water temperature.
Heater outlet water
temperature exceeds
210°F.
Set tank temperature
control for desired water
temperature.
FlHF) are used in conjunction
4
(Use this checkout for Cer-Temp 80 Recovery Systems)
SYSTEM OPERATION
Contact Incorrect
Circulating pump Pump and burner
and burner shut remain on.
off.
With thermal
balancer, pump off
delay of approx-
imately 2 minutes.
Circulating pump
on.
Burner on.
Circulating pump Circulating pump
and burner on. on.
Circulating pump
and burner off.
Burner on.
Circulating pump Circulating pump
on. and burner on.
System maintains.
desired water
temperature.
• The part no. 4920 pump contained in the deliming kit is
equipped with a titanium shaft. This shaft will not withstand
ammonium bifluoride solutions and must be replaced with a
stainless steel shaft, part no. 4926.
Ammonium bifluoride flakes should be purchased locally from
chemical suppliers. Contact your dealer, distributor or
A. O. Smith Water Products Company for additional information.
examined before using the checkout procedure. Be sure to refer
to the correct piping - wiring diagram and checkout for the type of
system that is installed.
The system should be filled with water, purged of air, valves
properly set and utilities connected and ready to operate.
Cause
Tank temperature control
differential wide.
Tank temperature control
defective.
System wiring is incorrect.
Pump wired for continuous
operation.
See intermittent pilot system troubleshooting chart 2.
Gas valve stuck or defective.
System wiring in incorrect.
Automatic gas shutoff
control calibrated too low
or differential too wide.
If system has been in
extended use it may
have lime build-up.
System wiring is incorrect.
Gas valve or wiring
defective.
See intermittent pilot system trouble-shooting chart 2.
Tank temperature control
differential too great.
Power off or system wiring
is incorrect.
Tank temperature control
defective.
See intermittent pilot system trouble-shooting chart 2.
System wiring is incorrect.
See intermittent pilot system trouble-shooting chart 2.
Automatic gas shutoff
control defective.
See intermittent pilot system trouble-shooting chart 2.
24
Remedy
Reduce differential.
Replace.
Correct wiring.
Correct wiring.
Correct or replace valve.
Correct wiring.
Replace. (If problem
proven to be at this
control by applying
jumper to terminals.)
See preventive
maintenance.
Correct wiring.
Check wiring repair or
replace valve.
Reduce differential. A 5°
differential is generally
used.
Check power supply and
wiring.
Replace.
Replace.
Replace.