Triangle Tube Outdoor Reset

FB

We had a Triangle Tube Instinct Solo 110 installed last fall. It replaced a Buderus GB 142-24. The Buderus outdoor reset always reported an outside temperature within about 3 degrees of the outdoor temperature measured a few inches from the outdoor sensor. The TT outdoor reset display is always from 8 to 12 degrees higher than the temperature measured near the sensor. All the temperatures noted are Fahrenheit. Both the installing contractor and TT customer service tell us that the 8-to-12-degrees above actual temperature is typical and not a problem. We find the house is a bit cooler than we like in the morning and evening and wonder if the outdoor reset is keeping the circulating water too cool. With the Central Heating demand set to respond to Thermostat and Outdoor Curve, we've tried three different Outdoor Curves: Radiators 1, 2, and 3. Radiators 3 has a maximum set point of 158 degrees F. That was near the maximum temperature we ever needed with the former boiler. Now on a 30-degree morning the outdoor temperature displayed is 42 degrees. The circulating water never exceeds 122 degrees and that is displayed as the Target Temperature. We set the daytime temperature to 68 degrees. Any advice or suggestions about improving this performance are welcome.

Zman

Is it the triangle tube sensor that came with the boiler?
Is the hole where the wire exits the building directly behind the sensor? If so, it may help to seal the hole so warm air from the space does not affect the reading.
If you have a multimeter you can verify that the sensor is not the issue by comparing the Ohm reading to the spec in the manual.
You should be able to program a custom curve to compensate as a last resort.
8-10 degrees off is not normal!

FB

Thanks for your reply Zman. The sensor is the one that came with the TT boiler. The wall is well insulated and the hole is well sealed. I will look for that ohm value and check it. You confirmed my belief that the outdoor reset display is too inaccurate. I hope one or two additional pros from Heating Help will agree with us - need to convince TT and the installer.

kcopp

How long is the run out on the wire?
If the wire is too long OR the wire too thin that will create issues too.

pedmec

Match up the ohm reading with the expected temperature. it should be in the manufacturers literature. 10k = 76 degrees.

FB

Hello Kcopp. The installer simply reused the same wire that had been connected to the previous boiler.