Suck start my boiler

Nope. There should not be. The boiler gets a good clean and check every year. Indeed, the fire side is an absolute bear to clean, but I make sure it is very clear. I bought this boiler as a quick replacement - the piping lined up very nicely with my old boiler in 2020 (availability???). There are likely better choices out there if I do more research and have the luxury of time to allow for piping changes. It is five and a half years old. The water sits up on the stainless perforated plate (it's horizontal) and gets stuck in that material between, effectively blocking most of the flow; allowing some as I can smell the raw gas outside on ignition attempts. It's just the gas/air mix is either way off and/or getting through nowhere near the ignitor due to the restriction. I reported this to the local HTP representative's service technician last year for his information and possible input.

The inlet and outlet vent piping is quite short and an appliance temperature 20 degrees below the dew point outside is my strong suspicion. The exchanger itself is dry, so I believe the moist air drifting in is mostly from the inlet piping, through the combustion blower and onto the burner surface.

I do run quite low temperature radiant and stay in condensing range for my domestic as there is only two people in the house and don't see the need to go super hot for that. This has only occurred during these high dew points, not in heating season. It recovers plenty fast and I have enough mass in the floor that I never notice any drop in floor temperature during domestic production in winter.

I do appreciate the input and will be that much more attentive during the next cleaning or sooner if this is a repeat occurrence before then.

Jay W.

I have ruled out a leaking heat exchanger. Feed water has been shut off since last service, September, which it gets every year at that time, by me. Only then to check compression tank precharge pressure and refill. Agreed, condensate back-up would be an obvious issue, but trap and exchanger was draining properly before and after. Condensate is ordinarily produced during combustion and flows downward, through the fire tube heat exchanger. This is a whole different scenario, where water is stuck where the engineers never thought it would produce condensate or take in water. This is clearly outside the norm, which is why I brought it to the Wall. Thank You all for taking interest. My service experience was more on the A/C side on computer room A/Cs and such, but had to cover anything they threw at me. Never saw this, but my leading cause is still what I laid out. You don't need a bunch of air flow, just a difference in water vapor pressure; I too, was amazed how much water had collected on the face of the burner the first time, when I took it apart. I only had to pull it out and set it on it's side to get it to drain. I will share any new findings if they show up again. And, yes, I shut the boiler off before the vacuum trick…. Did I mention that one really sharp tech that trained me early on earned the nickname "McGyver"?

Jay W.

Dew point in the 50s today; no worries….