Triangle Tube B18 E18 Error

Ducky24

I have a Triangle Tube Solo 175 from 2007 hydronic heat. While heating the house, the temp on the boiler is around 150-170, and when the thermostat shuts off, the temp shoots up over 202-215 degrees, causing first the B18 error, then E18.

I have replaced the sensors and the smaller circulation pump. Triangle Tube won't talk to me because I'm not a contractor, but they only told me the pump is not running.

My plumber told me to wire the pump to an outlet just to keep the pump running, but that just caused more error codes.

I don't understand what else to do but replace the boiler unless there is a way to have the pump run longer after the thermostat shuts off to bring the temperatures down.

If you have any ideas, I'm open to help.

**UPDATE: Added Photos**

Teemok

With out pictures or an understanding of how your pump is wired it's hard to say what's happening.
As you seem to be aware E18 is a supply sensor limit reached code. No circulation is the likely cause. Parameter 32 is your post purge Central Heating CH pump run time. That's only relevant if the boiler switches it.
If the boiler is not piped with 2 pumps ie primary/secondary and you have zone valves, the last closing valve could prevent flow regardless of the pump being on and residual heat in the heat exchanger can give you an e18.
But...... I'm speculating and you haven't given enough info. A real model number, pictures of all the components and a history would be good.

"but that just caused more error codes."
Wiring the boiler pump to constantly circulate shouldn't cause any boiler codes. It might burn out the pump depending on the piping.

EdTheHeaterMan

Do you have zone valves?
can we see a picture of the near boiler piping from floor to ceiling?
Is this a new condition? When did it start?

109A_5

Hello @Ducky24,
Is this a new problem or is it from 2007 ?

109A_5

Hello @Ducky24,
How long does it actually run for ? Maybe got switched to off ?



https://cdn.triangletube.com/wp-content/uploads/2021/08/10180622/2019-06-Prestige-Solo-Installation_Maintenance-Manual.pdf

Ducky24

I have added some photos for more context.

@EdTheHeaterMan Yes, I have two(2) zones but only use one

@109A_5 This is a new issue in the past year.

Teemok

I'm assuming that hidden pump under there is a 2nd zone pump and not a boiler pump. Not piped primary secondary. Which pump is the zone pump you use? Where is it wired to the control board? What's the heat emitters? Radiators, radiant floor, fan coils, etc.? Parameter 32?

Teemok

Pump on the left is pumping the wrong way! You are pushing water into the boiler where hot water should be coming out. Returning water to the supply port of the boiler. It's hard to tell how the expansion tank and fill valve is connected.

pedmec

When was the last time you had a PM done on your boiler? Having a temperature rise that will trip your high limit after the boiler is shutdown is an indication of a plugged heat exchanger. You need to have the heat exchanger inspected and cleaned.

Teemok