Compressor manufacturers at the IAHR Expo in Dallas offered an increasing array of variable capacities, improved servicability features for contractors and technicians, and additional features to enhance the units’ lifetimes.

From Bitzer comes the C Series two-cylinder, compact, semi-hermetic reciprocating compressors for use with R-134a, -22, -404A, -407C, and -507.

There was also a compact screw compressor, the CS 75 Series, which is used with R-22, -134a, and -407C. The unit features a low profile and light weight for small cabinet applications. The series also offers step or infinate slide capacity control. A built-in separator is made by Bitzer.

Contractors will appreciate the slinger oil system and internal motor winding protection, which is said to offer quicker response to over-current and over-heating conditions. The company says it drops into other compressor applications without remounting.

Copeland continues to expand its existing lines, but also introduced the CR line of reciprocating compressors. The Small CRKQ is available from 1 to 21¼2 hp with a more compact frame design, and is meant for room air conditioner and mini-split applications. It is said to achieve greater reliability at high ambients, and low sound and discharge pulse (lower vibration).

The company announced a SystemPro™ fractional and integral hermetic expansion with low-temp CF Models for commercial refrigeration applications. “They are especially suitable for use in walk-in coolers,” said Kurt Gobreski, market manager for refrigeration.

Available in a variety of displacements and voltage options, and compatible with R-404A and -507, the models feature an “optimized” motor, redesigned discharge port and reed, and special gasket and piston dome geometry.

The Compliant Scroll® R-410A line will expand in 2000 to include 1/2-hp units and a total of 30 model offerings in 50 and 60 Hz, plus three-phase models.

Then there’s the Summit™ Compliant Scroll® expansion for the commercial market — a 10-hp, three-phase model for R-410A and new tandem compressor configurations (7.5- and 10-hp units).

These configurations can be found in chillers and split systems, and are growing in popularity due to their design flexibility, the company said.

In addition to increased hp, the tandems offer modulation capability because the compressors can operate independently or with each other.

Finally, there’s an addition to the Contour™ screw line — an infinite capacity control model for air conditioning applications.

The patented design is said to allow infinite or four-step adjustment to meet precise temp control demands. A slider valve provides capacity control from 25% to 100%.

Danfoss introduced a 13-ton scroll unit, the S 161, which will be in production at the end of March. Designed for heavy and light commercial a/c, from chain stores to hospitals, it will be used in air-cooled package rooftop units, condensing units, and chillers that use R-22, -407C, and -134a.

This redesign of the SM 160 (which will not be phased out) “will be a lower cost unit that doesn’t sacrifice performance,” according to product manager Leon Bailey.

It features a smaller shell and brazed construction. The target market is lighter commercial applications, where contractors don’t need a heavy-duty product, like the SM 160.

Also from Danfoss in 2001: The 20- and 25-ton S Series 300 for commercial-industrial applications. The unit will operate with R-407C.

Embraco introduced the VCC variable-capacity compressor, which is said to operate continuously by varying cooling capacity over a range of 3:1 using electronically driven motors with a reciprocating mechanism.

It offers commercial refrigeration contractors up to 40% lower energy consumption, lower average noise levels, and “better food conservation through temperature stability, and quick freezing at higher speed,” the company said.

New from Louis Allis Hermetics: A complete reciprocating line up to 180 hp (and up to 200 in the next month or so), said general manager Richard Hankee. This product is going to the oem.

It’s been proven in Europe, in Italy, he said. The manufacturer is reintroducing the technology to U.S. hvacr.

The recips feature an “absence of vibrations and pulsations”; absence of suction and discharge valves, with high tolerance to liquid slugging and low flow losses; and “silent” running (average 8 dBA less than equivalent recips, and high-frequency noise emission that is said to be easier to soundproof).

They also feature high-efficiency capacity control; simple installation (a built-in oil separator allows installation of the compressor without any additional component); and compact design with reduced overall dimensions and lighter weight.

Tecumseh came out with RJ and RK rotary horizontal units — reliable, quiet, and with easier access for technicians due to their horizontal placement.

And there are scrolls from Tecumseh — the SA line from 40,000 to 60,000 Btu. The “Orbitec” is said to “surpass industry benchmarks for scroll technology in every reliability test to which it has been subjected,” the company said.

Horizontal scrolls are said to be coming next year.

The manufacturer’s “service-friendly” condensing unit has valves on high- and low-pressure sides, so a service tech can close and change pressure without dumping the refrigerant from the system, said “Sandy” Fordeck, manager, technical service & training, Aftermarket Division.

It has enough valves to pump the system down without dumping the charge. Electronic controls are accessible on the front.

Fordeck was also promoting his brainchild, the “Tech Trainer” unit. This actual mock-up of the basic refrigeration cycle “can mimic 95% of all service problems in the field,” he said, for high- and low-temp refrigerants.

To troubleshoot, students must have gauges, a temperature-measuring tool, and a pressure-temperature chart. The special show price: $4,495.