I looked up いる in the OJAD Pitch Accent Dictionary, which shows every verb conjugation and the pitch accent of each conjugation. 要る and 入る, and 居る and 射る were conjugated as I would have expected, as godan and ichidan verbs respectvely (listed as 1グループの動詞 and 2グループの動詞).
However I was surprised by the conjugation of 煎る, listed as ichidan:
- 煎る・煎ります・煎って・煎った・ 煎ろう were all conjugated like a godan verb,
- 煎ない・煎なかった・煎させる were all conjugated like an ichidan verb, and
- 煎りろ, the imperative form, is just weird.
Is this just a mistake in the dictionary, or is 煎る an irregular verb? If it is, what pattern does it follow?