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Re: Electrical Heating Option for Toddler's Room
Easier than hard wiring. Probably the 700 watt option suffices. I retired many 1500 watt oil filled radiators with 400 watt models.

Re: Electrical Heating Option for Toddler's Room
» High mount so the wire can come down thru ceiling to top of heater. Heater could be on inside wall but exterior wall recommended.«
Yes about high mount. Regarding recommendation; wall opposite exterior may be better for dealing with condensation on window?

Re: Electrical Heating Option for Toddler's Room
Just make sure it is wired to an adequate circuit.
Re: Electrical Heating Option for Toddler's Room
The brand, IIRC, was Qmark/Marley. The hangers go into slots on the back to allow for minor sliding from expansion/contraction. Maybe a slight click or ping as they operate. Quieter than a CI rad as it heats.
High mount so the wire can come down thru ceiling to top of heater. Heater could be on inside wall but exterior wall recommended.
Wall tstat, recommended versus unit mount, can go under heater. 240 volt heaters.

Re: Lochinvar / Knight Boiler 80-285 Issues
kinda hard to do this from connecticut, without being there and touching,
my bet is on the middle(upper) red circ, which I believe is your primary circ getting heat to your zoning, either electrical or mechanical(seized/stuck), can't tell, or it could be air bound, as was mentioned earlier,
was the system noisy when it worked last? could you hear the water flowing last winter?
and what Homer says, these boilers like to be massaged every year or 2, but it's heating the domestic so hold off there, I do see your pressure up around 30, that's too high, 12-15 is a target, so once you re establish flow, follow up on the expansion tank and pressure,

Re: Boiler sizer-
Weil McLain CGa is the simplest offering the Weil McLain offers today. It is basically the same 76% efficient CG boiler they introduced in the 1960s with a few tweaks to make it more efficient. To get to the minimum 80% AFUE they added electronic ignition to eliminate the standing pilot, and added a vent damper to close off the vent connector to the chimney to keep the heat in the house during the off cycle.
That said, your Hydrotherm was probably installed when plumbers thought "Bigger is Better" and is probably oversized. In my opinion, you have 2 choices. Keep the boiler you have as long as there is no signs of leaking boiler sections. the parts in that boiler can be replaced as needed for a lot less than a new boiler install. The moving parts like a circulator pump, gas valve, limit controls and other interesting things can be replaced with new upgraded stuff.
The other option is to get a new boiler that will not offer you any real savings over the Hydrotherm. The efficiency will go from 77% to 83%, which will save you about 8 cents on the dollar of gas usage. But getting the proper size, like perhaps the CGa 6 at 166,000 BTU input, if it is large enough may add a few more thermal efficiency points to reduce short cycling. Then you may get your total savings over 10%. That choices is not going to break the bank in fuel savings. but the load calculation will let you know that you do not need to use the CGa 7 at 200,000BTU input (because they don't make a 180,000 BTU input boiler.
If you go the new boiler route, the CGa 5 may even be enough for you, Have your contractor do the load Calculation for you. You may be surprised.
Re: Lochinvar / Knight Boiler 80-285 Issues
When was the last time the boiler"s heat exchanger and sensor cleaning? Service Due is probably a reminder to do a service after a programmed length of time in the boiler's program. The time is set in the programing. Much like a maintenance reminder lite on your car's dash.
Re: Simulating my home heating system for fun and profit
This is interesting stuff…. The folks at Brookhaven labs can take the winter off now!