Thema "Betreff: Short burns on 333-F (WS3C)" in Gas

Short burns on 333-F (WS3C)

ducttape — Wed, 03 Nov 2021 23:13:08 GMT

Hi guys,

I have a ~10y old 333-F WS3C. Recently I've noticed it's sometimes doing short 30 second burns. The issue is apparent on the attached image (green is the burner power in % and purple is the kessel temperature).

I don't know if it's related, but there are also some messages in previous months with fault code A8 - Internal pump reports air.

Any help would be appreciated!

Betreff: Short burns on 333-F (WS3C)

ducttape — Sun, 07 Nov 2021 20:37:11 GMT

Another day, even more short burns (~1min). Around 40 starts in four hours. Any ideas?

Betreff: Short burns on 333-F (WS3C)

qwert089 — Mon, 08 Nov 2021 08:03:46 GMT

Hi,

either you have air in the system and the water flow is not enough because of the air --> vent the air from the system and radiators

OR the heating pump has a mailfunction and must be replaced

Betreff: Short burns on 333-F (WS3C)

ducttape — Mon, 08 Nov 2021 13:17:54 GMT

Hi, thanks so much for you help! I vented all the radiators a couple weeks ago at the start of the heating season, there was no air in them.

I am thinking, could that be related to the fact that most of the radiators being closed. Since it's not so cold right now my parents don't have all radiators turned on (only 3-4 out of about 12) and there being less water in the system to ciculate? Or is that irrelevant?

Besides the radiators, is there another circuit that needs to be vented?

Betreff: Short burns on 333-F (WS3C)

qwert089 — Mon, 08 Nov 2021 15:16:32 GMT

Hi,

the boiler itself has also a venting valve.

But this normally only need after installation.

https://www.viessmann.com/etapp/parts/de/0500/7246899

probably the small number used radiators is the problem.