NY -- Standard&Poor's CreditWire 4/29/98 – Standard&Poor's today raised its ratings on Connecticut Health and Educational Facilities Authority's higher education revenue bonds series A and C to double-'A'-plus from double-'A', issued for Wesleyan University. The rating upgrade is based on strong debt ratios and a low debt burden. The university has not issued long-term debt in 10 years and expendable resources ($403.3 million) cover outstanding debt 8.4 times (x). Other rating factors include: -- Excellent demand flexibility, -- Above-average student quality indicators, and -- Strong operating liquidity and endowment levels. Wesleyan University is an independent, liberal arts institution located 15 miles south of Hartford, in Middletown, Conn. For the past several years, Wesleyan has maintained a