Ductless Split System Related FAQs

Q: How do EMI Ductless Split Systems work?
A: EMI ductless split air conditioning systems are the ideal solution when traditional central air conditioning systems are not practical or feasible. Designed for economical and efficient zone conditioning, ductless split systems utilized in commercial, industrial, institutional and residential buildings allow the owner/occupant the flexibility to satisfy most conditioning requirements.

A ductless split air conditioning system is one in which the indoor unit- the air handler/evaporator- is connected to the outdoor condensing unit by electrical wiring and refrigerant piping. EMI units may be located up to 100' (30.5 M) apart, including up to 35' (10.6 M) of lift. A minimal 3 inch (76 MM) exterior wall opening is required to allow for the wiring and piping. Utilization of ductless split systems allows you to condition various zones to meet usage requirements economically and efficiently, while achieving maximum occupant comfort levels.

Unique to EMI are 2, 3 and 4 zone multi-zone systems that allow up to four separate evaporators, each an independent circuit, to share one outdoor condensing unit, with up to 4 tons (14.0 KW) capacity. Each circuit includes an independent compressor, valves, lines,controls, etc. Only the cabinet and fan are common to each circuit. Because each evaporator operates on a separate circuit, the evaporators styles and sizes may be mixed or matched to satisfy both sizing and air circulation requirements.

All heating options are to be FACTORY INSTALLED ONLY (Please refer to bulletin 01004). Check the specific evaporator specifications for all available options.

Q: Can I purchase EMI ductless split systems directly from EMI?
A: EMI sells its products through an extensive distribution network. Distributors sell product to HVAC contractors. Because the handling of refrigerant is involved in the installation of the systems, only qualified HVAC contractors should install the products. Please use our Manufacturers Reps List to conveniently locate the nearest EMI Distributor in your area.

General FAQs

Q: Can I order supplemental heat for both cooling only and heat pump systems?
A: Yes. Supplemental electric heat is available on most EMI systems (factory installed only). Check the specific evaporator specifications for all available options.

As a reference guide please refer to the SIC condensing unit specification sheet to compare the capacities of the other manufacturer’s unit to an EMI unit (bulletin 01010). EMI will not warrant use of EMI heat pumps with other than approved EMI evaporators.

Q: Can I use your evaporators or condensers with other companies' units?
A: Yes, in straight cool applications. EMI will not warrant use of EMI heat pumps with other than approved EMI evaporators. Please refer to pages 15, 16,or 17 of the Service and Technical Guide (STG).

Q: Do your units come charged with enough refrigerant to cover the condenser, evaporator and line set?
A: No, the condenser comes precharged with refrigerant for the condenser and an evaporator allowance. You will have to add additional refrigerant based on your line set size and length.

Q: Does EMI provide anti-short cycle protection in its systems?
A: ASCT is a standard feature on EMI evaporators.

Q: Does EMI supply 24V remote thermostats?
A: EMI offers a selection of 24V remote thermostats. However, others may be used. When selecting a thermostat "by others", be sure to select an HVAC thermostat compatible with a 24 Vac, Heating/Cooling system. If the system is a heat pump with back up electric heat be sure to select a single stage cooling 2-state heating thermostat.

Q: Each circuit in an out door unit has its own number, so how does the numbering system work?
A: We use the following number system for each circuit. It is: 9 = 9,000 BTUH 2 = 12,000 BTUH 5 = 15,000 BTUH 8 = 18,000 BTUH 4 = 24,000 BTUH 3 = 30,000 BTUH 0 = An unused/empty circuit Each indoor unit has its own circuit, which is independently controlled. Evaporator styles and sizes may be mixed in over 600 combinations in two, three or four zone systems.

Q: What is the difference between heat pumps that are listed as limited range or max. range?
A: A limited range heat pump is not a defrosting unit in heat mode. Heat pump operation ceases at approximately 35 degreees F (1.6 C) outside temperature and electric resistance heater in the air handler (if supplied) is the sole source of heat. The 52HA, T2HA, T3HA, and T4HA Series of outdoor units are limited range heat pumps. S1HA single zone condensers are maximum range heat pumps, which operate with to 0 degrees F with defrost cycle.

The S1HA condensing unit will energize the electric heater on the indoor evaporator (if supplied) during the Defrost Cycle to dampen the cold air that is discharged off the coil during the Defrost Cycle.

Q: How many wires will I need to pull for connection remote thermostat applications?
A: You will need a minimum of three to a maximum of six, depending on combinations of straight cool or heat pump, with or without supplemental electric heat, etc.

Please refer to (bulletin 01020). This bulletin displays the proper number of conductors to pull between the indoor and outdoor unit.

Q: If I need parts for my unit what information do I need to provide?
A: To ensure we get you the correct parts, please ensure you have the complete 15 digit model number and the unit's serial number.

Q: Metering devices vary, so what type of meter is used in EMI evaporators?
A: Depending on the unit, EMI uses a piston device (chatleff assembly with a fixed orifice) or TXV.

Q: Once I have a Return Authorization from you, how long do I have to return the parts to the factory?
A: 90 days.

Q: What is the criteria selecting the low ambient option?
A: If the system will be operating for extended periods of time at 60 degrees F or below the low ambient option should be added.

Q: What length line sets are allowed for your units?
A: You can run up to 100 ft. (30.5 M) maximum length, to include up to 35 ft (10.6 M) in vertical rise. Consult the IOM or Tech Guide for P-trapping requirements within the run.

Consult the Installation and Operation Manual (IOM) of the outdoor condensing unit or the Service and Technical Guide (STG) for P-Trap requirements for the refrigerant piping run. These documents can be obtained from our website under the Product Literature heading.

Q: Where is the transformer located in an EMI system?
A: In an EMI system the 24-volt transformer is usually located in the outdoor condensing unit. If you are using an EMI evaporator with other than an EMI condensing unit, you MUST add a 40VA transformer. Please refer to (bulletin 01019) for more details. Effective December 1, 2004 all America Series products will be manufactured with the 24 volt transformer mounted in the air handler. Please see Product Bulletin 04001 for more details.