An Alternative to Minichiller

Condensing units can be divided into two types. The first one includes specialized units based on chillers, let's call them . The second one are the usual outdoor units of powerful split systems – . Over the past few years these devices have become a serious alternative to mini chillers as a cold source for central conditioners of the lower and medium capacity. Thus, about 1,170 condensing units worth 6.9 million euro were sold in this country in 2004. For comparison, 973 low power chillers worth 13.7 million euro were sold in the same period. About 180 of these units were used as cold sources for precision air conditioners with water cooling evaporators, and we might as well count them out. If we look at the process in its dynamics (see Charts 1 and 2) the market preference for condensing units is obvious. What is the reason for it? In the first place it is lower price. Let's compare retail prices of three possible cold sources for smaller-capacity central air conditioners. For the sake of the integrity of the experiment we shall take the equipment of the same brand, in this case – Carrier. (see Table 1).

Russia. Share of different types of coolers in the capacity range up to 100 kW

The data hardly needs any commentary. Outdoor units of powerful split systems are very often 4-5 times cheaper than the same capacity chillers. The expense of energy and cash on choosing and buying the necessary automation devices cannot even partially diminish this immense advantage.

Table 1. Comparative prices of chillers and condensing units (CU) in different power ranges, _

Type	Series	Capacity, kW
Type	Series	21	26	29	37	47	58	67	79
Chiller	30RA	9098	9872	10680	20749	24580	26501	28128	29426
CU	38RA				14732	17412	18689	19568	20255
CU *	38HDS	2086	2461	2615	3329	4922	5231

*For the comparison to be more correct, the price of the necessary automation devices should be added to the price of condensing units.

The price difference is not that big (usually about 30-35%) when chillers are compared to condensing units built around them. Condensing units are substantially less expensive because they don't need an additional cooling water circuit with a heat exchanger, a pump, a flash tank or automation devices.

The only limiting factor with condensing units is their capacity ceiling. The capacity of outdoor units of split systems with majority of manufacturers is 25 kW, in some cases 60 kW, and the most powerful ones – 130 kW. The most powerful condensing units built around chillers – 80 kW ones, more rarely 150 kW, and in some exceptional cases 300 kW and over.

Russia. Dynamics of sales (number of units) of different types of coolers in the capacity range up to 100 kW

In the second place, many regional companies do not want to meddle with water systems because of lack of specialists qualified for the job. But the first reason is more weighty. A number of companies with qualified personnel at their disposal rely on condensing units to the extent that they change projects of design institutes to adapt them for condensing units. Thus the building owner gets a less expensive solution which very often determines the choice of a contractor.

The comparison of prices of chillers, condensing units and condensing units easily explains the dynamics of these segments reflected in the charts. It is obvious that the demand for condensing units grows fast while that for condensing units is stable but very conservative. Meanwhile the sales of condensing units of major part of brands (with the exception of CLIVET, CARRIER and BLUE BOX) have dwindled. One cannot exclude the overall slackening of growth rates and even slow stagnation of the segment.

Table 2. Sales comparison for chillers and CU (2004)

Type	Capacity, kW
Type	0-25	25-55	55-100	100-200	over 200
Chiller	438	270	265	330	517
CU *	174	93	43	10
CU *	770	80

*All equipment of Clivet and York brands was classified as , since it has the corresponding automation devices.

At the same time the share of condensing units can grow drastically for the three reasons, to call the major ones:

Clearly lower prices compared with competing alternatives.

Extension of condensing units product line towards higher capacities.

The fact that the choice of automation devices together with AHU is no longer a problem. The necessary expertise is already available. Moreover a number of manufacturers and suppliers offer complete and ready-to-use automation sets, as, for example, Daichi with its package for Daikin condensing units.

The market structure of condensing units and chillers depending on their capacity is worth a separate note (see Table 2).

It is obvious that the share of chillers in the overall sales of cold sources for central air conditioning systems gradually grows with higher capacities. This share is only 32% in the capacity range up to 25 kW, is 61% in 25-55 kW range and is predominant in the ranges over 55 kW. It is 86% in the range 55 – 100 kW – almost 97% in the range 101 – 200 kW. And, finally, there is practically no alternative to chillers when one needs over 200 kW of power.

The share of condensing units, on the contrary, diminishes with the growth of needed capacity. Outdoor units of split systems prevail in the range of up to 25 kW (55%) while in the range 25 – 55 kW their share DROP to 18%. One can rarely see the use of more powerful outdoor units. At present only McQuay equipment with this feature can be found on the Russian market. The share of the condensing units is the highest in the range 25-55 kW, (21%) where it is above that of the condensing units. With the growth of capacity the share of the condensing units gradually goes down. Though, in recent years the share of more powerful equipment in this category slowly grows.