I have basement unit heaters that I have defined as heating ventilation
systems because the basement has makeup air connected to an ERV system. I
get this error message for all of these systems and a huge amount of
unheated hours. If I change either the design temperature or max entering
air temperature to match the other, I get an error saying that the air flow
will be to high (which makes sence).

Any suggestions?

**WARNING*******************************************************************
***
PREHEAT/HEATING-CAPACITY in SYSTEM EL1 Sys1 Unit Heater (B.C1)
is too low to provide the requested supply temperature for
the calculated mixed air temperature using total ZONE loads
(on LS-A/B) and SYSTEM design parameters, plus outside air
conditions (on LS-C), and specified capacities & air flows.
Requested temperature is 90.00 calculated is 70.00
Check HEATING-CAPACITY, HEAT-SET-T, PRE-HEAT-T, MAX-SUPPLY-T,
DESIGN-HEAT-T, and ZONE loads for consistency.

Eric J. Cody