what to measure

Bob Eh?_2

Outside: Air Temp, Wind speed, Wind Direction, Humidity, Incoming water temp and volume, Fuel volume to boiler/heat pump.

Inside: Temperature (By area if possible), humidity, DHW temp and flow, Solar insolation, Heat source run times, boiler flow/differential temps/supply temps, Heat distribution temp (supply/return) and flow, Differential air pressure inside to outside, flow and run times of fans/HRV equipment (Including temp of makeup air injected)

Sample minute by minute and calculate hourly values. You should be able to derive pretty much anything you want from that data.....

Real fanatics (Hi!) can expand from there to monitor/ assess the performance of structural assemblies, emitters, etc. ;-)

Bob

jerry scharf_3

what you would like to measure

After reading the thread about the puzzling seasonal efficiency and ME's post about snowmelt, the general idea came to me to poll the group about what should be measured in the ideal house.

Things that came up are outside air temp, incoming water, insolation. Inside air temps for sure. What else?

Also, what is the appropriate logging interval? Assuming you want to have long term raw data, what is a good compromise of size and information? Let's assume that everything goes to a PC, so sample storage approaches infinite capacity (an 80G disk is a whole lot of samples.) This is independent of the sampling rate needed for control of the system.

Toss your ideas out, I'll gather it up at the end.

jerry

Mike T., Swampeast MO

Both Left Out Something VERY Important

FLUE TEMPERATURE!!!!

I was able to do pretty well with flue temp, supply temp, return temp, outdoor temp (south in the sun), outdoor temp (north in the shade), indoor temp (5 locations on three floors) and condensate production. Three minute read interval.

Doesn't hurt that I have a Vitodens driving a fully TRVd system as there aren't any digital thermostats to complicate things...

In all honesty however, I still had to resort to degree days for consumption comparisons. I did record daily gas use for 2-3 week intervals during representative periods for fall cool down, winter cold and spring warm up.

What I don't have however (and would love to have) is logging of actual burner operation to include run time and modulation level.

Was planning on direct comparisons between old (cast iron) and new (Vitodens) boiler this year. Easy because I need only flip two switches and operate four valves. With natural gas so expensive this year however I SERIOUSLY doubt I'll waste both the money and the gas.

I do have wind data (intensity and direction) but haven't integrated into my monitoring program. From what I can see, the result is entirely predictable--delta-t increases slightly with wind...

Believe it or not, electric will actually be cheaper heat here this winter. 5¢ kw/hr as opposed to $1.50 therm (minimum).