1980s computer controls GRPS heat and AC

1980s computer controls GRPS heat and AC


A 30-year-old computer that has run day and night for decades is what controls the heat and air conditioning at 19 Grand Rapids Public Schools.

The Commodore Amiga was new to GRPS in the early 1980s and it has been working tirelessly ever since. GRPS Maintenance Supervisor Tim Hopkins said that the computer was purchased with money from an energy bond in the 1980s. It replaced a computer that was “about the size of a refrigerator.”

The computer is responsible for turning the heat and the air conditioners on and off for 19 school buildings.

“The system controls the start/stop of boilers, the start/stop of fans, pumps, [it] monitors space temperatures, and so on,” Hopkins explained.

A Kentwood High School student programmed it when it was installed in the 1980s. Whenever the district has a problem with it, they go back to the original programmer who still lives in the area.

Parts for the computer are difficult to find, Hopkins said. It is on its second mouse and third monitor.

“It’s a very unique product. It operates on a 1200-bit modem,” said Hopkins. “How it runs, the software that it’s running, is unique to Commodore.”

Hopkins said the system runs on a radio frequency that sends a signal to school buildings, which reply within a matter of seconds with the status of each building. The only problem is that the computer operates on the same frequency as some of the walkie-talkies used by the maintenance department.

“Because they share the same frequency as our maintenance communications radios and operations maintenance radios — it depends on what we’re doing — yes, they do interfere,” Hopkins said.

If that happens, “we have to clear the radio and get everyone off of it for up to 15 minutes.”

If the computer stopped working tomorrow, a staff person would have to turn each building’s climate control systems on and off by hand.

A new, more current system would cost between $1.5 and 2 million.