“We have 32 boiler rooms feeding 1,168 units with an average distance from the heater to the unit of 250 feet, much of it underground and around corners,” said Glenn Reynolds, property manager of the community. “Getting the right boiler and pump combination to move the heat swiftly and evenly has been a much bigger part of this job than I thought it would be when I signed on 10 years ago.”
Each boiler room sports a primary/secondary system with three 16-unit residential buildings on each loop. The total average line length served by each boiler room is 400 feet, a challenging application made more so by the age of the apartment buildings, Reynolds noted.
“We’ve had so many different pumps installed over the years that it became a real maintenance hassle. Whenever we had a problem, the repairman we dispatched had to keep five to 10 different pumps in the truck because he didn’t know what he’d find when he got to the room,” Reynolds said. “During 30 years, standards such as R factor change and pump designs change. Keeping everything running is a challenge.”
Even piping standards have migrated from the 1/2-inch line common in the 1970s and 1980s to the 3/4-inch line common today, changes which affect not only the size of the pump necessary to work on the line, but the flange connections and the baseboard space needed as well.
One of the changes Reynolds has recently implemented is a switch to direct-coupled in-line single stage circulating pumps — TP 50, TP 60, and TP 120 pumps from Grundfos Pumps of Olathe, Kan. — replacing a number of older pumps that didn’t have the flow to accommodate the sludge and calcium buildup caused by the mineral-heavy well water used by the complex. The TP pumps have very loose tolerances and are typically used in aggressive applications characterized by hard water and aging pipes. In addition to providing the high-flow necessary to tolerate the minerals in the system, the pumps are also designed to require only minimal maintenance — the replacement of a mechanical seal every several years, says Grundfos.
The renovation also includes a new boiler set-up currently being tested that will pipe each room’s two boilers in a twin loop on the same line, reducing by half the number of pumps necessary to provide heat.
Currently, all of the boiler rooms except the 12 test rooms have separate primary/secondary systems, each with their own pump. The switch to the TP pumps has cut the maintenance time needed for each boiler room where they are installed.
Universal Supply, of Wharton, N.J., the local plumbing supply house, identified the pump problem with help from a Grundfos representative based on an analysis of the failure rates of the previous pumps and recommended the switch to high-flow pumps.
“We determined that the older pumps had sticking problems caused by the calcium and that we could upgrade them to a high-flow pump with a fairly straightforward swap,” said Pete Czyzewski, assistant branch manager, Universal Supply Group. “The range of configurations available in the Grundfos TPs made it easy to do a general replacement because there were pumps available that could deal with the many different sizes, flow, and head configurations demanded by the different applications.”
The pump sizing process wasn’t without trial and error, Czyzewski recalled, commenting, “Grundfos stood out by backing their products with service. It was Grundfos’ committed service people that helped us identify the problems with the previous pumps and identify the TP line as the long-term solution.”
The move to standardize the boiler rooms has also allowed Reynolds to add energy-efficient new boilers, which is expected to not only save money in operating costs but also reduce service costs.
The new boilers, Patterson-Kelley Thermifics, from Patterson-Kelley Co. of East Stroudsburg, Pa., incorporate modern controls that adjust for outside temperature before delivering heat to the units, which significantly increases energy efficiency by allowing for lower heat loss during transit. One boiler room is testing the Patterson-Kelley Modu-Fire boiler that incorporates a full modulation firing rate, in which the heat supplied to the units can scale from 1.2 million Btu down to 240,000 Btu.
Unlike standard boilers that operate with on-off controls, the Modu-Fire boiler is able to put out less heat more evenly to meet the variable load conditions with heating and domestic water requirements. After a successful test in 2002 confirmed the improved energy efficiency of the Modu-Fire boilers over the older cast-iron boilers used in the remainder of the complex, work began in 2003 to install the newer units in two additional boiler rooms.
“The Modu-fire boilers solved a lot of problems with short cycling,” said Dennis Miller, president of Miller Mechanical Corporation, Sayreville, N.J., the mechanical contractor who has handled the pump and boiler installations for Village Green. “The low turndown ratio of five to one when there is a low load means that the boiler can run at 20 percent of maximum and not cycle, even during cold weather. That cuts energy costs and provides superior comfort for the residents.”
While most of the calls were not the result of non-functioning systems, the volume did lead the property manager to make changes to protect resident comfort in the face of abrupt drops in temperature. In addition to switching to higher-efficiency boilers, Reynolds and his crew also took a more basic step — they insulated all of the garage doors in the complex with 1-inch foam.
“The next year we cut the calls to single digits,” he added. “The new boilers and the time we spent installing just a little more insulation paid off with a significant boost in comfort for the residents.”
These changes made a big difference to the property staff, which includes Reynolds, an assistant property manager, five superintendents, three groundskeepers, one carpenter, and one tile man, in addition to several administrative positions. “We do almost all of our repairs in-house,” he said. The staff is also responsible for repainting and refurbishing apartments each time a resident moves.
By switching to the new boilers and pumps, Reynolds has been able to keep visits to each boiler room to check for problems at once every 30 days, which has helped in managing the overall complex.
Village Green hosts a holiday gathering with sleigh rides, an annual horse pulled wagon, as well as seasonal recreation activities. Maintaining the grounds is a priority — the community has a large annual flower budget, for example.
Many needs — from utility maintenance to groundskeeping — compete for staff attention on a day-to-day basis. Reynolds needs to keep the time spent “underground” with the boilers at a minimum in order to keep the roads clear and the grounds groomed.
“The new system has us consuming less energy, using fewer pumps, and spending no time on pump maintenance,” Reynolds concluded. “I’m looking forward to getting all the boiler rooms upgraded.”
For more information on Universal Supply, contact Pete Czyzewski, assistant branch manager, 42 Meadow Ave., Wharton, NJ 07885; 973-366-1800; firstname.lastname@example.org; www.usginc.com.
For more information on Miller Mechanical Corporation, contact Dennis Miller, president, Miller Mechanical, Sayreville, N.J.; 732-539-8175; email@example.com.
For more information on Grundfos Pumps, contact Hans Kircher, North American HVAC segment director, 17100 W. 118th Terrace, Olathe, KS 66061; 913-227-3400; firstname.lastname@example.org; www.grundfos.com.
For more information on Village Green Apartments or Segal Realty Associates, contact Glenn Reynolds, property manager, 100 Route 46, Mount Olive, NJ 07828; 973-347-0131; www.segalandsegal.com.
Publication date: 03/24/2003