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Heater Install ?

RJJ

Co-Founder
Joined
Oct 17, 2009
Messages
2,940
Location
about 1' east of the white water
Would you approve this install?

IMG_0921.jpg


I failed it!
 
Re: Heater Install ?

rjj,

Can you PM me a link to the picture in a larger format? I would like to share it with our team of Inspectors. This topic was brought up at our meeting 2 weeks ago, and it illustrates several issues very well.

Thanks!
 
Re: Heater Install ?

kilitact said:
rjj; is this conditioned space??
If it is then it is still wrong as far as thermal envelope is concerned.

Our U-Factor minimum is my area is .35 or less and I never saw a basement window that met it. Those walls would then have to be R19 around here.

Now, if they insulated the walls and not the floor above therefore making the basement part of the thermal envelope, then they could get away with no duct insulation at all.
 
Re: Heater Install ?

Insulation is missing. The reason for the post is this is new with the heater sitting on the return duct. No support. The insulation inspection has failed. The heater installation has failed.

Zone 4 would r value of 10
 
Re: Heater Install ?

I wonder about the size of the return air duct and plenum. The water heater is not secured in place. CSST exposed to physical damage requires protection. The gas shut-off valve should be at the end of the CSST with a connector to the appliance. I can only zoom so far before the image is distorted but I can't see a shut-off valve in the cold water line. Are there condensation issues with both the furnace and water heater vents?
 
Re: Heater Install ?

RJJ,

Can you upsize or zoom the photo for clarity, or possibly submit another one?

FWIW, I didn't see a pan underneath the water heater either? Is there some

type of floor drain in-place?

.
 
Re: Heater Install ?

Insulation is missing?

Perhaps I’m missing something here.

I’m making an assumption that the problem is the basement wall is only insulated on the top 4 feet an this violates IECC 402.2.6

402.2.6 Basement walls.

Walls associated with conditioned basements shall be insulated from the top of the basement wall down to 10 feet (3048 mm) below grade or to the basement floor, whichever is less. Walls associated with unconditioned basements shall meet this requirement unless the floor overhead is insulated in accordance with Sections 402.1.1 and 402.2.5.

My question is if the designer used section 404 simulated performance alternative to show compliance, would this not be permitted. ( R values and U factors aside).

It seems to me 402.2.6 is trumped by 404.2

404.2 Mandatory requirements.

Compliance with this Section requires that the criteria of Sections 401, 402.4, 402.5, 402.6 and 403 be met.

I also noticed RESCHECK will allow basement wall insulation to be entered in this manner and produce a passing report.

Comments gentlemen. And ladies too.
 
Re: Heater Install ?

Basement walls no problem here. 2003 IECC

Administrative Rules ofMontana (ARM's)

24.301.161

© Subsection 502.2.3.6, Basement Walls, is amended by adding the

following: "Basement wall insulation below uninsulated floors, except for rim joists

and perimeter cripple walls, may be delayed until such time as the basement is

actually finished for occupancy."

The state skipped the 2006 edition & will adopt the 2009 then it will be required but for now it would be ok
 
Re: Heater Install ?

Picky, picky, picky! That arrangement just allows pre-warming of the return air prior to reentry into the supply ducts, silly! :lol: :lol: :lol:
 
Re: Heater Install ?

Was the appliance installation instructions for both appliances provided at time of inspection?

Duct work touching the floor would be a concern and furnace support, is there a floor drain, is condensate line fastened, gas line shutoff placement, power source (Romex) is it protected?
 
Re: Heater Install ?

AHU's in apartments do it all the time. The duct is non-combustible on a non-combustible floor. If the duct is a thick enough guage to support the unit then what's wrong with it? It is a bottom return unit so where is the code requirement it has to be supported from above or on it's own stand? Manufactures installation instructions may address it but I think the code is silent.
 
Re: Heater Install ?

RJJ,

I have a roof mounted commercial unit that weighs 4260 lbs. sitting on a sheet metal plenum that is 40'' tall. The plenum is 12'x6'. The contractor calls it steel plate rather than sheet metal and it is some thousandths thicker than the everyday plenum material. The plans tell us nothing and the contractor keeps showing me the catalog that shows the downdraft unit with a plenum attached. The roof was built up with glue-lams which the plans do include.

The contractor claims he has done this many times without a problem and he may be right. I have never seen such an arrangement so I requested engineering. It's a lot like a bowling ball sitting on top of a beer can. The can will support the weight but if you shake it, the can collapses. I am in earthquake country so I look for beer can construction. I may get surprised and it is fine but now that I've been thinking about it, it's been a few months since I have heard from them.
 
Re: Heater Install ?

tigerloose; this is a typical manufactures requirement for the installation of a roof top unit. I am sure if you contact the manufacturer or look in the installation manual it will have a minimum curb requirement for that specific unit. Don't forget to tell them the wind and seismic zones you are in. I have been going thru this fight here for about 5 years now and have found the contractor will not argue much when it is called out by the manufacturer

IBC Seismic Compliant Units

It is important to follow these installation instructions for all

IBC Seismic compliant McQuay Rooftop units.

IBC Seismic compliant McQuay Rooftop units can be

mounted to either a roof curb or a post and rail setup. If using a

roof curb, it must be specifically designed for seismic restraint

and be IBC seismic compliant (spring isolated or non-isolated

type seismic roof curbs are available). Typical construction of

a seismic rated roof curb is from structural steel framing and

contains seismic hold down brackets for attachment of the

rooftop unit (see Figure 21). Post and rail arrangements rated

for seismic applications are also available (spring isolated or

non-isolated).

IMPORTANT: An acceptable IBC seismic installation

provides a direct positive attachment to both the building

structure and the roof mounted equipment.

Refer to the roof curb manufacturer’s submittal drawings for

actual roof curb assembly, attachment details and rigging

instructions for both roof curb and post and rail arrangements.
 
Re: Heater Install ?

mtlogcabin,

Thanks for the info. I will check out McQuay on the internet. I knew there was going to be an engineered system involved.
 
Re: Heater Install ?

Carrier,York and others I have looked up all reference curbs must meet wind and seismic loads for the units they support. I am suprised this is an issue for you I thought you where in CA
 
Re: Heater Install ?

Well this is the first time I've encountered such a large installation with nothing more than a plenum for support, The usual configuration has ducts hanging from the roof structure with no part of the ducts visible from the roof. It's not an issue for me other than I questioned it but it is certainly an issue for the contractor.
 
Re: Heater Install ?

Tiger: I would call for engineered drawing for a unit whit such weight! First ? not seeing the plan will the roof support such a concentrated load. What is the gauge of the sheet metal? Then how is it attached? and so on!

pcInspect: Condensate goes to a sump pump then out side! Wire is in conduit/ no an issue!

Gas shut off is ok! The direction for this type of installation are not included. My real problem is not the arrangement of the return, but is the return capable of supporting the unit during its life. If the duct work fails then the unit will drop 8" could be an issue. And that ain't :lol:
 
Re: Heater Install ?

Two thoughts:

Are the basement walls insulated on the exterior?

Will there be a negative reaction between the duct metal (whatever that is) and the concrete?
 
Re: Heater Install ?

Heaven: The walls are not insulated on the exterior. Insulation is missing. That has since been corrected.

The duct for the air return is galvanized sheet metal. Still waiting for thickness an details to show it can support the unit. Contact with concrete? Interesting thought. Don't believe it is a problem.
 
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