Robertshaw SlimZone Deluxe ZONE CONTROL SYSTEM - Manual (Page 6)

3. SAFETY INSTRUCTIONS
• Leave all primary power disconnected until installation is complete.
• Sharp metal edges may cause damage to wires. Use care during installation.
• All installation must be in compliance with local codes and regulations.
• Installer should touch a grounded metal object before handling any electronic compo-
nents to avoid potential loss of internal computer programs due to static discharge.
• Use extreme care when handling any solid-state microprocessor device.
CAUTION:
To avoid short cycling of equipment, always disconnect HVAC equipment from the
control panel before overriding time delay.
4. APPLICATION AND DESIGN CONSIDERATIONS
• All zone control installations require that the HVAC equipment be properly sized for the
application to assure satisfactory temperature control and optimum system performance.
Refer to Manual J or equivalent procedures to determine proper equipment sizing. Zone
by zone load calculations are recommended.
• Use Manual D or equivalent to size ducts and select registers. Duct sizing is dependent
on the following:
- Total number of zones
- Number of heating and cooling stages
- Type of equipment
- Indoor air movers (PSC motor or ICM/EMC motor)
- Bypass air system
• Good HVAC design and a balanced air system are important criteria in all zone control
applications.
• Zone thermostat location is a key priority. Remember, the thermostat controls the tem-
perature and should be located within the zone and at a maximum distance from regis-
ters, return air grilles, and any internal or external influence that would cause a false
temperature indication.
• Proper bypass air is critical in maintaining constant system static pressures. The ∆p can
be increased to the equipment manufacturer’s maximum by decreasing airflow or by
recirculating some of the air back to the return air using a bypass system.
• Air conditioning is equipment specific and dependent on coil frosting. The entering wet-
bulb temperature and amount of cooling coil heat transfer surface will greatly influence
the amount of bypass possible. Most systems must deliver 320 to 360 SCFM per ton to
the space to prevent frosting. Low limit protection is always recommended in conjunction
with a bypass system.
• Heat pump equipment is specific and dependent on mild weather trip-out limits. Air con-
ditioning guidelines of 320 to 360 SCFM per ton should be applied to most systems.
• Entering air temperature to a blower motor should not exceed motor design tempera-
tures. A motor fully loaded at maximum CFM and static pressure with the return opposite
the motor should have an 85ºF guideline. A lightly loaded motor facing into the return
may be able to handle 110ºF entering air temperature.
• High limit protection should be considered when the increase in air temperature across
the heat exchanger exceeds the equipment manufacturer’s high limit lockouts.
SlimZone Deluxe
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