® The Right Choice SEALED UNIT PARTS CO., INC. PO Box 21, 2230 Landmark Place Allenwood, NJ 08720 USA 800-333-9125 • www.supco.
THE BENEFITS OF A/C HARD STARTS Since SUPCO®’s introduction of the 2-wire hard start kit in the late 1970’s, there has been a proliferation of different technologies offering various reasons and solutions to the same problems that spurred their initial development; an air conditioner that just will not start under “normal” conditions. We will explain the need for hard starts in the first place, along with the intrinsic benefits of installing one in an air conditioning system.
The start relay has normally closed contacts, so when the compressor starts, both the run and start capacitors are connected to the start terminal. This causes a very high current to go through the start winding when power is first applied. This high start current increases the starting torque of the compressor motor enough that the motor will start even though the refrigerant pressures haven’t equalized, or in an “under-voltage” condition.
Intrinsic Benefits of Hard Starts Along with the starting benefits of these devices, there are a few other solid reasons for incorporating their use in an air conditioning system. With the emphasis today on “GREEN” products, hard start kits qualify by saving energy and lowering monthly bills. Reducing start time by as much as 50%; a system with a hard start minimizes the “in-rush” current period during startup.
The 2-wire kit is the technician’s installation preference for its easy installation and proven success in the field for more than 30 years. The use of either a mechanical potential relay or electronic potential relay proves effective; with the electronic potential relay providing a backup timing safety. Both relays provide instant recycling in the event of short cycling of the air conditioning system.
For systems with capillary tubes or fixed restrictors, a Positive Temperature Coefficient (PTC) hard start device is recommended. Choose from 3 models in the SPP Series to match the application. Table 4 outlines the product specifications: Table 4.
SEALED UNIT PARTS CO., INC. PO Box 21 • 2230 Landmark Place • Allenwood, NJ 08720 USA 732-223-6644 • Fax 732-223-1617 www.supco.com • info@supco.
