GSZH5 Service Manual
85
SERVICING
- Connectors are oriented "down" (or as recommended by equipment manufacturer). - Arrange harnesses with "drip loop" under motor.
- Is condensate drain plugged? - Check for low airflow (too much latent capacity).
- Check for undercharged condition. - Check and plug leaks in return ducts, cabinet.
Using the wrong motor/control module voids all product warranties and may produce unexpected results.
You must use the correct replacement control/motor module since they are factory programmed for specific operating modes. Even though they look alike, different modules may have completely different
functionality. The ECM variable speed motors are c
Symptom
Possible Causes Corrective Action Cautions and Notes
- Stays at low CFM despite
system call f or cool
or heat CFM.
- 24 Vac w ires misw ired or loose.
- "R" missing/not connected at motor.
- Fan in delay mode.
- Check low voltage (Thermostat)
w ires and connections.
- Verify f an is not in delay mode -
w ait until delay complete.
- Perform motor/control replacement
check, ECM motors only.
- Turn pow er OFF prior to repair.
Wait 5 minutes after
disconnecting pow er bef ore
opening motor.
- Handle electronic motor/control
w ith care.
- Stays at high CFM.
- "R" missing/not connected at motor.
- Fan in delay mode.
- Is fan in delay mode? - w ait until delay time
complete.
- Perform motor/control replacement check, ECM
motors only.
- Turn pow er OFF prior to repair.
Wait 5 minutes after
disconnecting pow er bef ore
opening motor.
- Handle electronic motor/control
w ith care.
- Blow er w on't shut of f.
- Current leakage from controls
into G, Y, or W.
- Check f or Triac sw itched t'stat
or solid state relay.
- Turn pow er OFF prior to repair.
- Air noise.
- High static creating high blow er speed.
- Incorrect supply or return ductw ork.
- Incorrect or dirty filter(s).
- Incorrect blow er speed setting.
- Check/replace filter.
- Check/correct duct restrictions.
- Adjust to correct blow er speed setting.
- Turn pow er OFF prior to repair.
- Noisy blow er or cabinet.
- Loose blow er housing, panels, etc.
- High static creating high blow er
speed.
- Air leaks in ductw ork, cabinets,
or panels.
- Check f or loose blow er housing,
panels, etc.
- Check f or air w histling thru seams in
ducts, cabinets or panels.
- Check f or cabinet/duct deformation.
- Turn pow er OFF prior to repair.
- "Hunts" or "puffs" at
high CFM (speed).
- High static creating high blow er speed.
- Incorrect or dirty filter(s).
- Incorrect supply or return ductw ork.
- Incorrect blow er speed setting.
- Does removing panel or filter
reduce "puffing"?
- Check/replace filter.
- Check/correct duct restrictions.
- Adjust to correct blow er speed setting.
- Turn pow er OFF prior to repair.
- Evidence of
Moisture.
- Motor f ailure or
malf unction has
occurred and moisture
is present.
- Moisture in motor/control module.
- Replace motor and perform
Moisture Check.*
- Turn pow er OFF prior to repair.
Wait 5 minutes after
disconnecting pow er bef ore
opening motor.
- Handle electronic motor/control
w ith care.
- Excessive
noise.
- Motor starts,
but runs
erratically .
CHART CONTINUED FROM PREVIOUS PAGE.