Buderus GB142 doesn't always answer call for heat in early winter over the past 5 years

kencou

I have had a Buderus GB142 since 2011. I have noticed over the past five years that in early winter the furnace doesn't always accept the call for hear. The hot water always works. I first thought it had to do with the AM10 Outdoor reset control. I bypassed it last year and didn't have an issue until early winter again. I have resolved the issue with shutting thermostats and turning back on, shutting off the power and turning back on and pressing chimney sweep bottom a few times, then it will take call for heat a hour or so later. I am thinking it could be the supply and return sensors. I don't think they have ever been changed. It kind of makes sense why its always early winter. I never have received error codes. Any thoughts? Thanks

EdTheHeaterMan

Perhaps the cellular service is not so good where your boiler is installed, or maybe they just don't want to talk to you when you call...


But to get serious, there may be a warm weather shut down setting that is set too low. WWDS set to 60°F might be the problem. or maybe it is set to 65°F and you want heat wnd the boiler is being super efficient. Try setting setting to WWSD 70°F

kencou

I disconnected the AM10. Plus the outdoor weather has been 30 - 40 degrees.

Big Ed_4

Seems to be a glitch with the thermostat , first replace the batteries in the thermostat ......

kencou

Thanks for the reply. I have nest Thermostats. When the are on they do activate the circulating pumps. I assume that means they are working ok. Am I correct with that assumption. I guess I can swamp out one of the thermostats for a manual one to see if the boiler fires.

kencou

So its been almost 2 weeks now. The furnace appears to sometimes take the call for heat. About 1/2 hour to 1 hour later it stops heating. I then turn off all the thermostats, wait 15 minutes and turn them back on and then the furnace takes the call for heat. This can happen like 5 times a day. Just looking for some feedback as to what the issue could be. Thanks

kencou

I inspected the Taco control module and noticed the transformer is very hot. The zones were calling for heat but the furnace didn't go on. I shook the transformer a little and then the furnace started. I assume I need a new control module? Thoughts

kencou

Or is the nest thermostats causing the overload.

Jamie Hall

If the transformer is very hot, it's overloaded. It may still be working, after a fashion, but I wonder what voltage it is putting out under the overload? This is not likely to be a problem with the control board, but rather other power draws which it isn't made for. Ideally the Nests would all be powered off an independent transformer.

SteveSan

@kencou What is the part number of the Taco control you have and how many Nest t-stats do you have? Please be in front of the control and please give Taco Technical Services a call during normal business hours Mon-Fri 8am-5pm EST 401-942-8000

kencou

4 nest thermostats

kencou

thinking of replacing nest thermostats. Does anyone have recommendations for wifi programable thermostats that dont drain the power from the furnace. I do not have a c wire.

SteveSan

Can you supply the model number of the Taco control you have?

kencou

SR-506

SteveSan

You will need to add in an external transformer to handle the load coming from the 4 Nest t-stats.

kencou

Thanks

kencou

where do I add it? Do I need to add a C wire to the thermostats? Thinking it may be easier to get more compatible thermostats.

Jamie Hall

ALL wi-fi thermostats draw power -- whatever make they are. In fact, a surprising amount oof power. If you can dispense with wi-fi there are any number of battery powered programmable thermostats which work very well on a two wire circuit. But not wi-fi.

You will either need to add a common return (C) wire to your wiring and power them from a dedicated transformer in the basement, or use local power supplies for each one -- wall warts.