NOTICE: It appears that the new $200,000 pool heater system about to be installed by the Master Board may be inadequate to maintain an adequate pool temperature during the winter months and will cost more to run than estimated during the nighttimes. Consequently, operation of this heating system during these winter months may be a total waste of electricity because residents would not be using the pools during warm days if the pool water is too cold. It is not unreasonable to assume that these heat pumps will operate 80% of the time in the colder, less humid nighttimes and winters which are conditions that result in the least efficient operation of the equipment. Additionally, the new pool heating system will be noisier than the current virtually silent propane heating system. Those homeowners from The Estates and Sapphire Cove who are the closest to where this new heating system is to be installed need to be told how noisy this system will be. This will be particularly important in the winter when residents open their windows at a time when ALL of the many heat pumps are likely to be running 24/7.

I am a retired scientist and process engineer with a PhD in chemistry and I am very familiar with the thermodynamic and engineering issues involved in these type of systems. The following is my summary technical overview of the proposed pool heater system. It is probably too technical for most residents to understand but you should be able to get the basic idea that the colder air temperatures and lower humidities during the winter months coupled with winds will prevent the proposed system from maintaining the pool temperature at the desired level.

I have been attempting to obtain important information regarding the new pool heaters but the Association has yet to provide the requested information. (Click here to view my August 16th email to Matt Ball and the Board members to which I have yet to receive a reply.)

Using the information that has been made available to me, I have been unable to verify the return on investment calculations used by the BOD to justify this new pool heater system. What follows is my technical review of this proposed pool heater system.

The BOD should have an engineering firm review my SUMMARY TECHNICAL REVIEW so that the return on investment calculations can be revised appropriately and include estimates as to a) how many winter days, weeks or months the proposed pool heater system will NOT be able to maintain an adequate pool temperature and b) the level of noise that can be expected.

Bernie Amero, a Baywinder for Improved Governance Through Full Disclosure

SUMMARY TECHNICAL REVIEW

During the August 16, 2010 Master Board meeting, the BOD voted to go forward with replacing the current propane pool heater system with a heat pump pool heater system. The BOD's decision is based on engineering calculations that convert the current propane consumption to the equivalent electricity consumption of a new heat pump system (click here to see these calculations).

Basically, these calculations claim to show that a $200,000 heat pump system would pay for itself in energy savings (i.e., propane costs vs electricity costs) in a little more than 3 years. Unfortunately, from the information I have been able to obtain from the Association, the only way these energy savings will be realized is if the heat pump system is turned off and homeowners don't use the pools during the coldest months of the year .

The reason for this is simple. Unlike propane heaters, heat pumps loose efficiency as the air temperature goes down. In fact, as can be seen from the chart below regarding the heat pump system that our BOD is planning to install (i.e., the AE3000 curve), the heating efficiency of this system drops by 40% from an air temperature of 80 degrees to an air temperature of 50 degrees (i.e., 130kBTU/hr vs 70kBTU/hr).

In laymen's terms, what this means is that if ten (10) AE3000 heat pumps were needed to maintain a pool at an air temperature, water temperature and relative humidity of 80 AND with zero wind velocity then eighteen (18) AE3000 heat pumps would be needed to maintain the same pool temperature during those times that the air temperature drops to 50 degrees (i.e., 80% more heaters with substantial consequent equipment and electricity costs). Alternatively, the ten (10) AE3000 heat pumps would be unable to maintain pool temperature even running 24/7.

The above 40% drop in efficiency does not take into account the actual pool temperature setting, the variation in relative humidity and the lower nighttime air temperatures particularly during the winter months and wind velocity that dramatically increases the cooling rate of the pool water. It is not unreasonable to believe that a heat pump system three (3) or more times the size and the cost of the one the BOD is planning to install may be needed.

I offer the following for the BOD's consideration.

As can be seen from the table below, none of the average low temperatures in West Palm Beach even come close to 80 degrees. In fact eight (8) of the twelve (12) months of the year show average temperatures less than 80 degrees (i.e., the heat pumps will not be able to output their rated BTU/hr).

As can be seen from the table below, for the year beginning August 1, 2009 and ending July 31, 2010, the average mean and minimum temperatures are below the temperatures used to rate the efficiency of the AE3000 equipment. Please note also, the max and average wind velocities of 40 and 9 mph, respectively. These wind velocities would create further energy demand on the AE3000 equipment.

As can be seen from the table below, for this past month of January the average and minimum temperatures were well below 80 degrees, even reaching 32 degrees.

Turning now to humidity, the average mean and minimum relative humidities for January of this year were 64% and 45%, respectively. Again, the AE3000 equipment is rated at 80% relative humidity and the ability of these units to generate BTU/hr would be substantially diminished at these lower relative humidity levels.

Given the low winter temperatures and humidities the daytime to nighttime swings coupled with the wind velocity effect, it is possible that a heat pump system three (3) times the size of the one the BOD is planning on installing may not be able to maintain an adequate temperature during the winter months.

Finally, the new pool heating system will be noisier than the current virtually silent propane heating system. Those homeowners from The Estates and Sapphire Cove who are the closest to where this new heating system is to be installed need to be told how noisy this system will be. This will be particularly important in the winter when residents open their windows and all 15 heat pumps may be running 24/7.