Honeywell report addresses insulation found last week in Telstar air intakes
A discovery last week that insulation had been deliberately stuffed into ventilation louvers at Telstar in the 1980s does not change the need for a $2.5 million upgrade to the ventilation and energy systems at the complex, according to an engineering report issued Monday.
SAD 44 residents will vote on the proposed project Nov. 6.
In an audit done earlier this year, Honeywell had concluded that the 45-year-old complex has a variety of ventilation and energy efficiency problems. Engineers used the example of 45 mechanical heating and ventilation (HV) units located throughout the building, of which only two were bringing in air, they said. To compensate, teachers have been asked to crack windows, even during the winter, to ensure enough fresh air in classrooms full of students and prevent the buildup of carbon dioxide.
But last Thursday, after a Telstar teacher asked that a unit be checked to see if the filter was clean, maintenance personnel found fiberglass insulation had been placed just inside a louver located on the outside wall of the building. The louver is intended to allow air to be pulled inside from outdoors.
Supt. Dave Murphy said Honeywell was contacted immediately.
Investigation by company technicians Friday showed that 18 of a total of 36 original, fresh-air intake louvers in classrooms had such insulation, and a few also had cardboard behind them.
The discovery called into question whether the poor function of the units was due to mechanical problems or to blockage by the materials placed in the louvers.
Honeywell summarized its Friday investigation in a report sent to Murphy Monday.
The insulation was placed only in first floor units, technicians found.
A maintenance employee who worked for SAD 44 in the 1980s said he helped install the insulation around 1986, but he did not know why it was done, according to the report. Telstar Lead Custodian Arlynn Hale said that since she has been on the staff, there have been problems with frozen unit ventilator coils in both the first and second floor units.
Honeywell said the insulation showed signs of air movement because there was accumulated dirt on the incoming air side. The company concluded from that evidence that the material did not prevent movement, but rather acted as an air filter. Air flow could be “slightly restricted,” the report said.
Honeywell provided additional information to support its conclusion. The report said carbon dioxide readings taken on three occasions did not show a noticeable difference between the first and second floors: “The carbon dioxide readings do not support there being a significant difference in fresh air ventilation to the second floor compared to the first floor.”
In addition, a check of the controls on several HV units showed they “are not capable of operating in a way to provide ventilation while they are in heating mode,” which is most of the school year.
“We ultimately conclude that the presence of the fiberglass insulation behind 50 percent of the intake air louvers does not change or otherwise impact the need to replace the 45-plus year old unit ventilators with new units which are capable of providing ventilation at all times (including during the heating mode) in accordance with current ventilation code requirements.”
The insulation has now been removed. Honeywell said there may now be risk of “coil freeze-ups or room comfort complaints,” and the company will monitor the situation.
On Tuesday Honeywell engineer Bob Marcotte said that while he has seen instances of older schools deliberately blocking such louvers “during the oil embargo days” to save energy, those louvers were covered from the outside with a material such as plywood, which would effectively block air flow.
The Telstar insulation would not have been visible without removing the louvers, he said.
Marcotte said he has since learned from a former SAD 44 employee that the insulation was placed in 1983 to conserve energy.
But citing the Honeywell investigation, Marcotte said the material was not effective in preventing airflow.
Murphy said Tuesday he was pleased that Honeywell “responded as quickly as they did” to the situation, and that he was satisfied with their findings regarding the impact of the insulation on air circulation.
The six-page report, which includes photos, is available on the SAD 44 website at www.sad44.org/pages/MSAD_44_Bethel.