SETCURE
06-08-2009, 04:51 PM
We manufacture a line of water and air cooled water chillers specifically designed for supplying chilled water at a precisely controlled temperature to small heat exchangers, which we also make. It is a niche market.
Until a few years ago, our chillers used R22 with good success. At that time, our chiller capacity was derated on a percent capacity basis for every degree above 95 deg F (35 C). When the plant cooling water or ambient air reached 105 deg F (41 C), the capacity of our units decreased, however, they continued to provide chilled water. On really hot summer days, if our customers had cooling water/air above 105 F, they could limp along by lowering the process load.
We made a change to R407c to allow us to continue to sell to the EU and in anticipation of the upcoming change in US refrigerant regulations. With minor modifications to our designs, we have seen similar performance in our current chillers as compared to our R22 versions, with one exception.
Rather than simply losing some capacity at high cooling water/air temperatures, the R407c chillers seem to completely stop chilling above about 105 F. The drop off seems to occur at an even lower temperature with our air-cooled units due to the larger inefficiencies seen with the air-cooled condensers (especially with dirty coils). It makes it difficult to sell the air cooled units in warmer climates if the maximum air temperature is only 95 F (35 C).
What other refrigerant options are out there? Changing to higher pressure refrigerants will most likely price us out of the market, so we are trying to avoid those. Other U.S. manufacturers of similar units seem to still use R22. We don’t know what their plans are for 1/1/2010.
Any suggestions would be greatly appreciated. Sorry for being long-winded!
Until a few years ago, our chillers used R22 with good success. At that time, our chiller capacity was derated on a percent capacity basis for every degree above 95 deg F (35 C). When the plant cooling water or ambient air reached 105 deg F (41 C), the capacity of our units decreased, however, they continued to provide chilled water. On really hot summer days, if our customers had cooling water/air above 105 F, they could limp along by lowering the process load.
We made a change to R407c to allow us to continue to sell to the EU and in anticipation of the upcoming change in US refrigerant regulations. With minor modifications to our designs, we have seen similar performance in our current chillers as compared to our R22 versions, with one exception.
Rather than simply losing some capacity at high cooling water/air temperatures, the R407c chillers seem to completely stop chilling above about 105 F. The drop off seems to occur at an even lower temperature with our air-cooled units due to the larger inefficiencies seen with the air-cooled condensers (especially with dirty coils). It makes it difficult to sell the air cooled units in warmer climates if the maximum air temperature is only 95 F (35 C).
What other refrigerant options are out there? Changing to higher pressure refrigerants will most likely price us out of the market, so we are trying to avoid those. Other U.S. manufacturers of similar units seem to still use R22. We don’t know what their plans are for 1/1/2010.
Any suggestions would be greatly appreciated. Sorry for being long-winded!