5
SERVICE INSTRUCTIONS
Disconnect all sources of power before servicing unit. If it is
necessary to replace a factory installed part, be sure to use
Lattner replacement part. Replacement parts are available
through authorized Lattner representatives or directly from the
factory. When ordering replacement parts, always include the
model and serial numbers.
LOCATING TROUBLE
Problem
Possible Cause
1. Unit does not operate
Disconnect or control circuit switched off, low water
condition, high temperature condition, improper setting of
operating control.
2. Water temperature too low
Operating control set too low or not operating properly,
oversized circulator pump, or faulty
elements/fuses/contactors/wiring.
3. Water temperature is too
high
Operating control is set too high or not operating properly,
undersized circulator pump or not operating properly.
4. Water temperature correct
but building is cold
Circulator pump not operating properly, air blocks in piping
or radiation, control valve in supply or return piping not fully
open.
5. Excess pressure causing
relief valve to open
System head pressure exceeds relief valve setting or
expansion tank water logged.
Lattner Boiler Company
1411 9
th
St. SW
Cedar Rapids, IA 52404
Telephone: (800) 345-1527
Fax: (319) 366-0770
Web: www.lattnerboiler.com
