Fireplace vs boiler

The boiler is going to win in the efficiency game and the comfort game in the end. The fire place is a reasonable though inefficient t space heater while the boiler is designed to make the whole house comfortable. If the boiler is truly a gravity system the radiators can be adjusted for each space.

Fireplaces are really nice to look at and warm a space but as far as efficiency numbers it really depends on the type of gas insert you have. Is it sealed? does it have a fan.

You posted a week or so if I recall. Something about the boiler and fire place debate. I think the recommendation was to replace the burner? I don't know much about that burner btu surely there are other far more efficient gas burners that could be retrofit to that boiler. The boiler appears to be functional although with some outdated features. There's always a rock and a hard place. Updating the boiler will in the long run be more efficient and likely more comfortable. But I will cost some, while the space heaters are doing the job now. It's a cost benefit thing I guess. We hate to see a nice old hydronic system gathering dust.

Any open hearth fireplace is grossly inefficient. The Canadians measured a typical 36" woodburning fireplace firing with a face velocity of 0.8 m/s and a draft pressure of -0.04 wci, you would typically lose 400-600 CFM up the stack of room air you already paid to heat.

Vented gas logs require the damper blocked wide open 24/7/365 or removed. They typically fire at 50 mbh or greater.

Ventfree logs are 99.9% efficient but, YOU are the chimney. Breathe deeply. Every 3 hrs. you dump a gallon of water into the home. They stink, can legally emit 200ppm CO, produce aldehydes, NOx and they stink.

A direct vent gas insert is typically about 65% AFUE, uses 100% outdoor air, zero indoor emissions, is a great zone or supplemental heater, typically fire at 30-40 mbh, and are heater rated so they can run thermostatically. During a power outage, you can run the burner on batteries. If you have a forced air duct system, you can circulate heated air throughout the home instead of turning down the burner once the room heats up.

A boiler of any kind is typically a primary heat source, unlike any type of fireplace.

Comparing a fireplace to a boiler is sort of like comparing apples to bananas.

The big opening was a draft regulator and the small hole was likely a damper. These were removed when the boiler was converted from coal to gas. These will be addressed when a modern burner is installed.

Maybe. Let the installer determine that after a combustion test.

"They used a no trespassing sign with wire to block it" I think that would be fine for the time being if your chimney is clear. that boiler will be making enough heat that there should be a vacuum at both of those openings. With the boiler running you can check this with a candle. Hold a lit candle to the opening and you'll see the flame get pulled inwards toward the opening. Try with the boiler off for a while, I bet you'll see a draft as well.

Get a co detector and put it down there.

I would imagine that flue would suck your hat right off, especially while the boiler is running.

Yes, most reputable thermostat manufacturers supply plastic wall anchors and screws in the box. That's plaster, so pre drill with a masonary bit. You supply the pocket level. Set CPH to 1.

Hi, I think the small dial you refer to, just under the main dial, is called the anticipator. It's used to regulate heating cycles and prevent overheating. 😰

Yours, Larry

You very likely don't have to worry about that setting at this point. That anticipator is there to adjust/ prevent over or under shooting the thermostat set point.