Adding Second Floor heat.

[Joe004]

Last winter I had a Well McLain Ultra 200 Installed.

Soon I am going to be adding some heat up stairs. I could use some direction.....

It is currently a monoflo system for the first floor.

Right Now I believe I am to add a circulator on the return and cut in a T to bring the water upstairs with a zone valve? Attached is a photo of the current system.


Also this thing seems to fire even when the thermostat is off. Is this normal?

 

[Dana]

The photo didn't take.

Is it really an Ultra 230 or possibly an Ultra 299 ?? (I didn't know there even was a 200 in the Ultra Series.) Either one of those boilers is ridiculously oversized for the average house in Massachusetts. Even at it's minimum-fire output the Ultra 230 could heat my 1920s vintage 2400' bungalow (+ ~1600' of conditioned basement) at outdoor temps of -15F or so. Even a nearly uninsulated 10,000 square foot house wouldn't need an Ultra 230. (Most houses in MA wouldn't even need the Ultra-80, but for a single zoned system or high mass systems it would still be fine.)

The only thing that might be saving the thing from short cycling itself into an early grave is the high thermal mass of your system. Do you have big high volume radiators &/or fat pipe on your monoflow loop? What are the burn times like?

If you're adding a second zone it's important that there be sufficient thermal mass and radiation to manage the 46,000 BTU/hr minimum fire output of the 230 (60K for the 299) to keep the burn cycles reasonably long.

If the mono-flow loop is always circulating even with no call for heat the boiler will occasionally fire. But if there's no flow through the boiler when there is no call for heat it should not be firing. Are you also heating domestic hot water with it, using an indirect (operated as a second zone)??