The software that I use asks for the model and serial numbers of the furnace, air conditioner & the water heater. Getting that information is very time consuming for me & I wonder if it is necessary. My wife doesn’t know ours! Does anyone report on this stuff or should I delete these components from my software?
Roy Drangstveit
I report estimated age and fuel suply of HVAC and Water heater. I report size of water heater.
I do not note serial numbers or make of any system or equipment.
I do. The numbers are a great way to tell the age without estimating in most cases. The only time I estimate is if the numbers are unclear, or the labels are somehow unreadable.
I agree it is very time consuming, and would rather not do it. I’ve found a little trick that helps sometimes. If I am dropping off a radon monitor a couple of days prior to the inspection, I get the numbers then, and have them already keyed into my report prior to showing up. This does two things… It speeds up my inspection on the day I am doing it, and it also lets me give my client the radon results the same day. (One I did earlier this week, I noticed a problem with the furnace when I got the numbers, and even had my comment already written and in place.)
I do use the serial numbers and model numbers to estimate age, I just do not write the numbers down in my report. 
I once had a seller exchange his newer condenser for an older one after my inspection. The buyer, my client, called me later because of some difficulty running the unit and I stopped by. I may not have been able to determine that an exchange had taken place without the serial number being recorded in my report.
I always put the numbers in my report. That way, when the client or seller says I didnt inspect the unit, I can say, yes is did - how do you think I got the serial numbers.
A very quick way to get them is to take a picture of them, just as I do for appliances. That way if there is a later question as to what appliances were there (we all know that the seller wouldnt change them out with cheaper units) there is some proof.
If I can find date info through serial numbers I do.
Not required , but it is a big help.
I just add the photos anymore. 
It would not hurt to add a picture of the serial and model either, though maybe you do that.
I realise that is not always easy to do though,which is why it might be helpful to the property owner if he calls info somewhere and the plate or sticker numbers go missing.
I have seen where a lazy serviceman might remove the plate.
Ditto…no numbers…no age…if they look old recommend replacement—:lol:–:lol:
I usually report on S#'s and M#s, just in case some sleezy owner tries to swap out on the sly.
I usually set my camera to macro and take a picture of the data plate. When I add the picture into the report, I can just look and add the numbers into the fields in the report. I don’t bother with estimating or obtaining the age though.