Basictroubleshootingtechniques - Friedrich PTAC Series Installation & Operation Manual

920-087-04 (8-05)
K. BasicTroubleshootingTechniques
Being familiar with the sequence of operation on Standard Controlled Operating Units or the operation of the Remote Thermostat
Controlled Units is important. The following questions and answers may help to identify performance problems.
EnvironmentalEffects- CoolingMode
Is unitsizedto roomsize areaand heat loaddemand?
The number of people in the room, number of electrical devices,
solar gains, etc. are all variable items that can affect proper
sizing of the unit. Friedrich recommends that you consult with
an applications engineer for proper sizing.
Environmental Effects- Heating Mode
Is unitproperly sizedto roomarea and heat loaddemand?
The number of people in the room, number of electrical devices,
solar gains, etc. are all variable items that can affect proper
sizing of the unit. Friedrich recommends that you consult with
an applications engineer for proper sizing.
Is the outdoor temperature 60°F or below?
The unit is designed for outdoor temperatures above 60°R
Isthe indoor temperature 80°For above?
Ambient indoor temperatures of 80°F or above will take a longer
period of run time to cool down the area. Long run times may
indicate that the unit is undersized.
Is indoorhumidityhigh?
This condition will cause the unit to operate longer to remove
humidity before noticing any cooling effect.
Has the heat load been increased by additional devicessuch
as computerequipment, or has the roomarea been increased
where the unit is located?
If conditions have changed, the unit may not be able to cool and
condition as effectively as previously planned.
Isthe outdoortemperaturo70°For above?
The unit is designed for outdoor temperatures below 70°R
Is the indoor temperature 60°F or below? Ambient indoor
temperatures of 60°F or below will take a longer period of run
time to heat the area. Long run times may indicate that the unit
is undersized.
Hasthe roomarea been increasedwherethe unitis located?
If the area where the unit is located has been increased, the unit
may not provide adequate heat.
Insufficient Maintenance and Inspection
Installationerrorsare themost commoncause of poor performance.
Please follow installation instructions carefully. If other problems
exist, see Maintenance and Inspection Troubleshooting Guide
below.
Maintenance and Inspection Troubleshooting Guide
CAUSE RESULT
System is not serviced or inspected Can result in premature component failures, poor performance and
regularly (semiannually or annually), increased operating costs.
Air filters are not cleaned regularly and May result in poor cooling, icing and water problems as well as
become blocked with particles, component failures and increased operating costs.
Condenser coil not maintained
May result in poor cooling, component failures and increased costs.
properly (blocked with particles).
Evaporator coil not maintained properly May result in poor cooling, icing and water problems, and increased
(blocked with particles), operating costs.
Components that show signs of fatigue May result in multiple service calls, poor performance and
- not replaced, increased operating costs.
Condensate drains and drain lines not May result in water and odor problems.
maintained.
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