Tarm shutting down during startup

I don't know about the Tarm but my eko with the ekoster 2 controller has a "start" cycle which will shut down the boiler if it has not achieved 70 °C in a given amount of time. It's been so long since I've read the manual, I don't know if the temperature or duration is adjustable. Whatever mine is set at works fine for me. several small splits loaded to a level just above the bottom of the door opening starts going pretty fast.

If I push it too fast I have had the same problem. Just get it going good before you load it up and you should be good to go.

This perplexes me. I've never had this happen, now entering the 5th heating season. I assume when you say "when you turn the fan back on" you mean that you have to reset the Solo 40, right? As best as I know this only happens when the sensor in the smoke box cools below the setting on the dial under the cover and on top of the controls. It seems odd that with a bed of coals, fire start-up, this would happen, but I suppose it could if you failed to get a good fire going, hot enough to engage the shutdown control, and then the smoke box cools down to shut off the draft fan.

From what you are saying, there seems to also be a time element in the control like my eko.

If I start from scratch with a kindling fire, then toss in a couple of larger chunks and walk away the temps will come up and then drop off and shut the blower down if I don't pay attention to it. If you have already started a fire and have a good bed of coals it should not shutdown. What are your flue temps like when you have it shutdown?