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Jim Luttrall
04-09-2009, 02:45 PM
Just did a Condo last Saturday with 3 stories plus a roof-top deck and mechanical room.
They had the tankless direct vent water heater and a standard efficiency furnace inside a mechanical room with no provision for combustion air for the furnace. I called it and have been back and forth with the builder. His plan is to put in louvered grills in the door.
My main concern is the pex manifold is in the same room and is mounted on the outside wall with no insulation behind the manifold.
I think pretty much everything is in the works to be fixed, I just thought I would post it here for your viewing pleasure.
BTW, the builder is having to retro fit every unit in the complex since none of them have combustion air provisions. I don't know how it got approved by the city unless they were assuming a sealed combustion furnace.

Nolan Kienitz
04-09-2009, 05:37 PM
.... and no sediment trap, no P-trap & insulation on condensate lines .. and ... and ...

it seems to never end. ;)

Jerry Peck
04-09-2009, 06:14 PM
Is that furnace room insulated?

If so, it is not going to be (might as not have been) when that combustion air duct is cut through the wall, not unless a proper heat exchanger is installed to keep that cold air from entering that small mechanical room without being tempered and brought up close to ambient in the room, otherwise that room will just get progressively colder as though no insulation were present and everything in there will freeze - might as not not both with the manifold piping in that case.

That does not look like the vent has the minimum rise, or am I not looking at it properly.

Is that Type B vent all the way? Single vent would not be allowed there.

Many things could be added to Nolan's list.

wayne soper
04-09-2009, 06:33 PM
fan in a can can be set to operate only wher furnace is running yes. = all the other stuff

Jerry Peck
04-09-2009, 07:35 PM
fan in a can can be set to operate only wher furnace is running


Which is when there is cold air outside, which is when you least want to draw cold air in (that's why the room is insulated in the first place), which means that you have just mechanically defeated the insulation, which means that room will freeze, which means everything needs protection from freezing, which means ... OMG ... :eek:

Bob Spermo
04-10-2009, 09:40 AM
I thought gas tankless on-demand water heaters required a double walled stainless vent?

Jim Luttrall
04-10-2009, 11:18 AM
The vent looks like the one in the installation manual.
http://www.rinnai.us/documentation/downloads/U287-07701_VA_Series_Indoor_LS_Manual.pdf
page 31

Rick Hurst
04-10-2009, 01:42 PM
Jim,

Was that condo over in Addison? I've seen that building, but can't place exactly where it was.

rick

Jim Luttrall
04-10-2009, 03:30 PM
Hope Street just off Greenville Ave and La Vista south of the "M" streets.

Rick Hurst
04-10-2009, 03:51 PM
Thats it. I did one of those awhile back.

Does these look familar?

rick

Jim Luttrall
04-10-2009, 03:56 PM
Yep, I did the second one in, the builders model.

Mike Schulz
04-11-2009, 02:11 PM
Ahh Rick it sounds like you need to make an addendum since Jim said the builder needs to correct all the units.:eek: