Hi, 

We have a CI project and we are specifying a 18 kW tankless electric water heater, table 7.8 from ASHRAE 90.1-2010 does not specify any requirements for this type of heater as it does not a storage capacity. However the technical data sheet indica an 98% efficiency but not an SL. Can we consider this as it does not have minimum performance requirements and do not include it in the mandatory requirements?

Thanks in advance 

Kind regards