Ideal Exalt Wall 155 vs 199

The 155 and 199 are the two larger Exalt Wall heat-only models, both rated 95% AFUE with an 8:1 turndown. The 199 adds 44,000 BTU/h of input ceiling (199,000 vs 155,000 BTU/h), lifting DOE heating capacity from 142 to 184 MBH and the AHRI net rating from 123 to 159 MBH, but its minimum fire also rises to 24,875 BTU/h — the highest in the series.

Venting separates them in a practical way: the 155 lists 2-inch venting up to 28 equivalent feet as well as 3-inch up to 100 feet, while the official table lists only 3-inch venting for the 199. On a retrofit where 2-inch pipe is the difference between a straightforward run and a larger penetration, that detail can matter as much as the capacity.

Weight rises from 99 to 119 lb and water volume from 3 to 4 gallons in the same 21.75 x 26 x 16.5 inch cabinet. Both use the CTRLMax control with plain-text diagnostics, outdoor reset and DHW priority, both support an integrated cascade of up to six boilers, and both are heating-only, pairing with a separate domestic hot water source.