I hope you can take the time to help with my direct-vent fireplace choices.

I'm building a new home in San Francisco. It never freezes here, but its in the 50's and 60's for much of the year (even the Summer).

In any event, I'm planning to heat two rooms exclusively with direct vent fireplaces. The first is a 17'x22' living room (with 10' ceiling). The second is a 14x21 Master bedroom (with 8' ceiling). This strategy will allow me to minimize ducting, and give me better zoned control.

My mother-in-law works for a plumbing supply company, so I can get Kingsman Industries fireplaces at a discount.

Here's my question: I really like the look of the Kingsman "Designer Clean View" fireplaces. (They have no louvers.)

These only come, however, with BTU outputs exceeding 20,000. By my sqaure footage calculations, I need only about 9,500btus for the bedroom, and 11,000btus for the living room.

Is this OK? Will the oversizing mean that the fireplaces will just operate at a constant low burn, or will they cycle on and off?

Also, since these units are being used as heaters, should I get blower units? Or is this unnecessary given the high btu outputs?

Thanks in advance for your advice.

They may have a manual valve that will let you reduce the burn rate [and so, increase its time], but there things get complicated. Many gas FPs reduce output by opening an extra vent to dump the heat directly outdoors, which strikes me as very irresponsible.

Mendottas offer far more control in this regard, which makes them my choice. I want to be able to have a cozy little fire without getting blasted out of the room or [effectively] setting money on fire by letting the heat go up the chimney. BUT I have a separate heat system, too.

So check out the turndown rate and method: In a worst case scenario, you may have to leave the burners set as high as possible for efficiency, and let the thermostats turn them on and off as necessary. You can still have a fire when you want it by nudging the thermo, or keeping it low when you aren't around, raising it when you are actually there to enjoy the fire.

Most clean face units don't offer blowers, which would require louvers for the air flow: they are called 'radiant' heaters.

There are some downsides of oversizing to this degree. They'll cycle a lot, and since a gas FP needs to warm up internally to get the flame looking really nice, you'll spend more time with relatively poor looking flames, more time with none, and probably loose a little overall efficiency.