Hvac log

Blower speed, duct static, fan amps, compressor amps,model number, serial number,metering device and capacitor reading should be on there. Dont always need TESP but for sure note it if one of the other readings looks strange.

Dont always need TESP but for sure note it if one of the other readings looks strange.

I don't get it.

Total external static pressure. Dirty evap coil over a furnace, fire damper closed,too small of duct, filter looks clean but is plugged with super fine particals ect will all show up as a high TESP. Anytime you have a low superheat or low suction pressure it's time to check air flow and not just a hanky moves around in front of the register.

The log should also have coil entering and leaving WB and DB. The temp between the register and the coil can be very different.

Also with TESP. You can compare it to the manufacturers fan chart, and determine the actual CFM being moved. Then converting the coils entering and leaving WB to total heat, you can determine what capacity the unit was operating at, at the time of taking the measurements. And can break the capacity down to its sensible and latent capacity.

There are slide charts for TXV systems, that with the coils entering WB, gives you what the leaving DB temp should be for 400 CFM per ton. Its a great way to double check your air flow.

This can be very usefull on systems where the customer says it doesn't keep up, or doesn't cool fast enough.

Nice looking log.