Best Of
Re: New Crown boilers - updated piping
Did they repipe it after they installed it or is that how they installed it? As I see it they used a cheap vent and didn't fix some issues someone in the past left behind. They didn't do the best job but didn't do an awful job either.

Re: Air to Water Heatpump scenario for my abode.
"With the swt hardly breaking 140 at designed would an a2w hp be viable with the rads that I have? "
There's the rub. Both the output and the COP really fall off the table at cold temperatures when you raise the water temperature.
Let me ask this: Do you have AC? Would you like to have AC? As a rough back-of-the-envelope guess, based on your heating load and the weather station data I'd say your cooling load is about 1.5 tons. I'd think about two heat pumps, an air-to-water that does most of your heating, an air-to-air that provides cooling in the summer and more heat when the air-to-water can't get the water hot enough in the winter.
The other option would be adding more radiators or other emitters.
Re: Even more steam system questions……
Glad I was able to locate it, and acknowledge that it appears to be functioning properly. At the same time I was able look at a few pipes and connections behind finished areas to check for leaks, which I did not see any. Finished it off with a small 8 x 12 access panel for future viewing.

Re: Angle Radiator Valve for Balancing (with linear flow control)
Angle Radiator Valve for Balancing (with linear flow control)
It's a monoflow diverter tee system.
Radiators closest to the boiler overheat.
Dahl Canada used to make the following which have just been discontinued:

They have linear flow control for every turn of the spindle as opposed to a regular radiator valve which is apparently mostly meant for on/off and has 80% of the flow when 1/4 open which isn't useful for balancing
Does anyone know of a different valve i can use that's specifically meant for balancing?

Re: Anyone ever seen a duct system like this before?
There was a small duct, high temperature, low airflow system briefly popular between the late 1950s and early 60s. I've seen that once before. The supply air temperature was about 250° F and the original supply diffusers induced room air into the flow so the outlet temperature was lower.
I believe this system is no longer code approved. The high temperature furnaces have not been made in a long time, and so far as I know the only solution is a new duct system built to conventional standards, or a completely new heating system of a different type.

Re: Even more steam system questions……
Found it…..fortunately it’s at the far end of a storage area, so with an access panel I can make it look presentable if someone was to look at it. As if anyone was going to look in my storage area in my basement……
The 2 mains meet up about 3 feet away and run to this 90 degree elbow that the main vent sits on. The vent sits on top of the vertical pipe in my closet picture. So as my boiler was running I could hear the main vent release steam and then close. So it would appear that is functioning correctly. Is it necessary to run a vertical stub pipe and fit the main vent on top. I have the room. Nothing I would do now, that would be a summer task. Or leave good enough alone. The vent valve has to be over 20 years old. I have no issue replacing it once the heating season is over.

Re: Identify this radiator heating element and baseboard convector enclosure
Those are hose clamp thermocouples (see some of my other posts). They're an excellent way to get a consistent and long term temperature reading from a pipe! Slip them on and tighten them down for good contact.
Only downside that I discovered (the hard way) is that they have to be electrically insulated from eachother. So there's at least one layer of thermally-conductive electrically-insulating tape wrapped around the pipe and between the pipe and the thermocouple.
Re: Rinnai Cycling on and off
I finally received the replacement servo/bypass valve and it took me about 45 mins to install it. I now finally have a fully functioning water heater. That was it…
Many thanks to everyone for the ideas and suggestions.

Re: New Crown boilers - updated piping
It seems like at least this plumber specified a gordon main valve in his quote and didn't put that in. A cheap main vent will fail early correct? I paid for quite a bit of this on my credit card. If he refuses to change the main vent or doesn't respond, I could get a quote from a better steam guy, and contest the amount of that quote against the original plumbers charge on my credit card. Unless people in this group think this is a bad thing to do. I texted the plumber who put in the bad main vent once already about this and he has so far not responded. I will continue to ask him to make it right but I may have to go the credit card route.
He's probably done with you. If he specced a Gorton and put in that thing then yes, that was bad practice on his part. If you do a chargeback, you'll never have him as a plumber again (which might be a good thing). The Gorton would cost him about $45, the one he put on was probably under $20.
To me that's "walk away money" but maybe not to you, I can't choose for you.