is my Baxi duo-tec faulty?

nikanika0

Hello, I was crypto mining last 2 years in my living room with heat of 500W 24/7, I haven't noticed my boiler behaving this way, because I didn't use it much. Stopped in Sep, and started using GCH in Nov.

it is happening in 5 min intervals: 15:36 boiler flame light switches on and boiler kicks in, vapor coming out of flute. 15:37 flame icon off, boiler switches off, no vapor, 15:42 repeats switches on, 15:43 off, 15:48 on,15:49 off, 15:54 on, 15:55 off, this happens irrespectively to thermostat being on or off ( batteries in or out) and/or programmer being set to ON,BOOST,AUTO. 

Hartsmann 2 channel programmer (downstairs,upstairs), Honeywell DT90E thermostat set to 24deg to highlight the issue, flow 54deg, 6y old 2 bed end of terrace.
Can you help please? cheers.

MattMattMattUK

nikanika0 said:

Hello, I was crypto mining last 2 years in my living room with heat of 500W 24/7, I haven't noticed my boiler behaving this way, because I didn't use it much. Stopped in Sep, and started using GCH in Nov.

it is happening in 5 min intervals: 15:36 boiler flame light switches on and boiler kicks in, vapor coming out of flute. 15:37 flame icon off, boiler switches off, no vapor, 15:42 repeats switches on, 15:43 off, 15:48 on,15:49 off, 15:54 on, 15:55 off, this happens irrespectively to thermostat being on or off ( batteries in or out) and/or programmer being set to ON,BOOST,AUTO. 

Hartsmann 2 channel programmer (downstairs,upstairs), Honeywell DT90E thermostat set to 24deg to highlight the issue, flow 54deg, 6y old 2 bed end of terrace.
Can you help please? cheers.

Do you have TRVs? 

nikanika0

yes 5 downstairs and 4 upstairs all open on max, because I programmed my boiler to run 04.00-06.00 on Auto, and in the afternoon on demand I switch it on and off manually. this system suits me. I'm happy with 19 deg downstairs.

BUFF

when was it last serviced?

btw afaik most wireless thermostats default to "on" if they can't connect (i.e. batteries out).

nikanika0

never serviced, I am very low gas user and the house keeps its temperature well, hence programmed to 04.00-06.00 on AUTO only, the rest I switch manually on and off, that's why I don't need thermostat, it's set to 24 deg anyway.
today: 10.02 on, 10.06 off,10.09 on, 10.13 off, 10.16 on, 10.19 off, 10.22 on, 10.23 off, 10.26 on, 10.29 off. I will have to get it checked, crypto rig had really nice heating output.

InvertedVee

nikanika0 said:

Hello, I was crypto mining last 2 years in my living room with heat of 500W 24/7, I haven't noticed my boiler behaving this way, because I didn't use it much. Stopped in Sep, and started using GCH in Nov.

it is happening in 5 min intervals: 15:36 boiler flame light switches on and boiler kicks in, vapor coming out of flute. 15:37 flame icon off, boiler switches off, no vapor, 15:42 repeats switches on, 15:43 off, 15:48 on,15:49 off, 15:54 on, 15:55 off, this happens irrespectively to thermostat being on or off ( batteries in or out) and/or programmer being set to ON,BOOST,AUTO. 

Hartsmann 2 channel programmer (downstairs,upstairs), Honeywell DT90E thermostat set to 24deg to highlight the issue, flow 54deg, 6y old 2 bed end of terrace.
Can you help please? cheers.

I'm not a heating engineer but I looked up your boiler installation manual. Here's the extract which refers to the anti-cycling time being just 3 minutes:

I don't think you have any options to restrict the maximum output and with a simple on/off control, the programmer will be calling for maximum heat or nothing. The boiler will modulate itself when the return temperature rises but then shut down again. It sounds like your energy-efficient home doesn't need anything like the boiler's output. It's not an uncommon situation.

Some boilers can be adjusted in different ways to extend the anti-cycling period but I don't think that yours can.

nikanika0

My neighbour is a gas engineer, but this boiler on-off has got me worried, it's wear and tear even if it was designed like that, the noise is very intrusive, it's pretty loud in this small house.