Coil sizing check in E+

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Thank a lot for formula. But it's hard to determine all those input with standard report of E+ for zonal equip like PTAC. i got from HVAC sizing summary Cooling Sensible - User Design Load (W) - it's same as zone component load summary report for sensible peak load. But how to get coil total cooling capacity (sensible + latent) form that value? i divided Cooling Sensible - User Design Load (W) with Design Size Gross Rated Sensible Heat Ratio in Component sizing summary and it often 9 % less than Design Size Gross Rated Total Cooling Capacity in Component Sizing Summary report

I try to figure your suggestion for infiltration. In HVAC sizing summary has only

Indoor Temperature at Peak Load [C] Indoor Humidity Ratio at Peak Load [kgWater/kgAir]  Outdoor Temperature at Peak Load [C]    Outdoor Humidity Ratio at Peak Load [kgWater/kgAir] Minimum Outdoor Air Flow Rate [m3/s]    Heat Gain Rate from DOAS [W]

so infiltration load should be calculation as outdoor enthalpy minus indoor enthaply then multiply with design infiltration rate and schedule factor ?

If you are interested only in coil sizing, then infiltration will impact zone load and zone conditions. The values for indoor temperature and humidity ratio include the impact of infiltration and is therefore included in the sizing equation shown above.

in case indoor temperature and humidity include the impact infiltration, should i take the grand total latent value included infiltration latent load in Estimated Cooling Peak Load Components when checking total load for dehumidifying coil sizing ?

The infiltration load will be included in the reported coil total load since the coil entering air conditions will include the impact of infiltration.

So i just calculate all internal latent loads like people, kitchen appliances for this calculation ? . I make an humid stats inside each zone to make humidity control so i want to get the necessity humidity ratio of supply air = humdity ratio of room - humidity room load - have any reported variable for that sizing ? i saw the zone predicted moisture load to dehumidifying but not sure about its definition - which latent load is it included ?

The zone predicted moisture load to dehumidifying setpoint tells you the latent load in the zone. IF the zone humidity is at the set point, this is the load to be met by the HVAC system to reach the set point. IF the zone humidity is not at the set point, the predicted latent load also includes zone air capacitance and is not equal to the load needed by the HVAC system. The zone latent loads are typically people, infiltration, mixing from other zones, and any other equipment objects that have a latent component.

I want to make show typical DOAS/Dehumidfying coil sizing process, so i focus on latent load (gw/g dry air) only. In order to sizing coil, i need to consider all latent load and get supply air conditions met that latent load and the peak zone latent load and room condtions are main points what i want know. I get latent load value from Zone Component Load summary and room condition at peak load, however, 1/ i am not sure latent load only at that moment is peak over the sizing year ? You said that infiltration affected room condiditon at peak moment is HVAC sizing summary so i want to...

Add due to limitation : as manual, i use room temperature and Rel Humidity setpoint to get humdity ratio of room condtion and get peak latent load (gW/kgAir) then get supply air humidity ratio ->design supply air condtions and get dehumidifying coil sizing value. In component load summary, room peak condition different due to infiltration load, i also observe the zone predicted moisture load through sizing period and can not make an reasonable relation between it and component load summary - the only 2 reports have latent load information. how i demonstrate by E+ data ?

Sum the people latent and infiltration at the time of sensible peak (since you don't know the time of latent peak), this should be near the zone latent load. Sum the people latent, infiltration, and OA load at the time of sensible peak. This should be near the coil latent load. If the zone RH is not at set point at the time of sensible peak, then the zone latent load will also include what is required to get back to set point.

1/Maybe have duplicated sentences here. I tried to figure again Sum the all total latent (people, infiltration and OA load) at the time of sensible peak. -latent load form people and infiltration -> total latent load from component load summary and get OA latent load from coil sizing. 2/ . If the zone RH is not at set point at the time of sensible peak : if RH bigger than dehumidifying setpoint - includes the zone predicted moisture load to dehumidifying setpoint . If RH less than than dehumdifying setpoint - don't include zone predicted from component load summary. Is it right ?

2/ Other pathway : May i find peak zone latent load by observe zone predicted moisture load to dehumidifying set point through all sizing period -> supply air humdity ratio = room set point humidity ratio minus max value zone predicted moisture load to dehumidifying set point then plus OA peak load (from peak ambient to predicted supply air condition) ?

1/ this sounds like your on the right track, but remember I'm discussing this without verifying if my statements are exact. I know your trying to create equations for sizing, just remember what we discuss here needs to be validated. 2/ zone predicted moisture load is not an adder to coil capacity, it is a target. RH> include or RH< don't include isn't the correct approach. If RH<, the coil still has a latent component doesn't it? I'd rather discuss this with you on the phone to talk through everything. 2/ Other - will latent peak coincide with sensible peak? There's a lot to take into account.

Ok moved to email discussion!

With E+, How Can we get this report " Enthalpy outdoor (36oC, 0.02207g/kg) = 92.87 kJ/kg ;Enthalpy return air/room air (26oC, 0.01138 g/kg) = 55.21 kJ/kg....." ? Mentionned in the post.
Its the detailled calculations, I find this very interesting and could be very useful