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We present new maser emission from ^{14}NH_3 (9,6) in NGC 7538. Ourobservations include the known spectral features near v_LSR = -60 km/s and -57km/s and several more features extending to -46 km/s. In three epochs ofobservation spanning two months we do not detect any variability in the ammoniamasers, in contrast to the >10-fold variability observed in other ^{14}NH_3(9,6) masers in the Galaxy over comparable timescales. We also presentobservations of water masers in all three epochs for which emission is observedover the velocity range -105 km/s < v_LSR < -4 km/s, including the highestvelocity water emission yet observed from NGC 7538. Of the remarkable number ofmaser species in IRS 1, H_2O and, now, ^{14}NH_3 are the only masers known toexhibit emission outside of the velocity range -62 km/s < v_LSR < -51 km/s.However, we find no significant intensity or velocity correlations between thewater emission and ammonia emission. We also present a non-detection in themost sensitive search to date toward any source for emission from the CC^{32}Sand CC^{34}S molecules, indicating an age greater than \approx 10^4 yr for IRS1-3. We discuss these findings in the context of embedded stellar cores andrecent models of the region.

New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers