What system did you get? Because if it is an Infinity system, you might be ok. How long ago was the install?

Just a guess here, but I expect some manufacturers require certain standards from their authorized installers and you might have some recourse there.

David,

I got the system last October. Here are the specs

http://www.lennox.com/products/air-conditioners/XC16/
http://www.lennox.com/products/furnaces/G61V/
http://www.lennox.com/products/air-handlers/CBX32MV/

At this moment I'm just waiting for my BPI audit this weekend and then we will know. I'll post the numbers.

Thanks

Bluelogic

Ok, here we go.

BPI test shows that I'm only getting 1300 CFM out of 2000. The return is causing massive negative pressure. The static pressure is over 1.0. The return was sized to 20' when it should have been 25' for the air flow requirement. The 5 ton system was attched to a 2.5 ton existing duct worked and sealed. To add insult to injury the test also shows the AC staying in Cycle 2 (High) all the time.

I got the AC through a Home Depot Home Improvement Agreement. I called the installer and asked to have a sit down conversation about the system. Does anyone have any recommendations on how to approach this? My BPI auditor says I should have them fix the cycle issue, do a J load, to show me I need a 5 ton (not likely) system and have them give me a proper sized system (swap out), he also said they should also size my ducts (air balance) the home for each room, but I feel I'm at a disadvantage since I already have the system installed since October last year.....I can't just ask for a refund =(. What corrective actions should I push for without moving into the money issue. I wish to work out the issues with the installer one on one to come to some agreement; however, I fear they would use this as a chance to charge me more money.

Thanks
Bluelogic

I kind of expected that, which is why I waited to post
after your BPI inspection.

AC through a Home Depot Home Improvement Agreement...
didn't do you any favors did they?
been there - tested that!

ok, what you need is a new duct system. and if they sealed
it to that standard..at least they seal properly.
so thats a plus.maybe you can negotiate.

the negative is the size of the unit, and the r/a problem.
add the duct system to that and in my mind these are the
things you have to negotiate.

unless they are better educated than the bubba that contracts to HD here..they probably can't do a load calculation. And may get offended and cop an attitude.
this is not condusive to negotiation.

so how can we make it work?

if they would switch to 4 ton..in that perfect world..
but let's assume they won't.
at least you have vs. that alone saves a lot of bubbas.
they can set it on low speed (dipswitch settings) and it
will actually be more efficient, and remove more humidity.
not perfect, but a possible agreement.

R/A has to be re-sized..depending on the location..
in the ceiling..in a chase on the wall..this is non-
negotiable. R/A should also be well sealed.

Ductwork should be sized for the unit. no way around
that. In my mind this is the thing you will have to pay
for.

Offer them the chance to make it right.
Set dipswitches, fix r/a..come back when its cooler
and you have $$ and change ducts.

Granted its not perfect, but it has been my experience
that they will hork it up more,if they get pissed.
As the unit is not new..perhaps the leverage of them being contracted to hd will be enough to make them do the work.
its a peach connection for them to lose.

Did your BPI only test a/c, or did he/she do the
testing on your whole house?

best of luck.

Energy Rater La,
BPI Auditor is Silver, under the BPI site. He is also BPI certified, a Third party Verified Contractor with the California Building Performance Contractors Association (CBPCA.org), A certified Home performance With ENERGY STAR auditor, and works for CBPCA as a third party quality assurance inspector & tester.
Duct Leakage tested at less than 10%. I had a HERS done after the duct sealing per requirement in California.
The R/A could probably be fixed by either making it 25 or by installing a return in each room. Increasing the return to 25 is something they are open to so far. I like the return in each room instead because the return is in the main hallway on the top floor and it causing massive negative pressure that it is sucking air from my can lights from the attic. The company is blaming the home builder for not creating proper duct size and insists that is not their fault.
So far from talking to them it seems they dont have an idea what a J load is. The owner installed my system and he insists that I need a 5 ton no matter what. My BPI auditor said if they need a Manual J and Manual D he would do it as my consultant.

I have a nice furnace that can be changed by dip switch to 940 in Stage 1 and 1340 in Stage 2. My system max is 1300 cfm with the current duct work.

The problem with them working on the duct work is that the home builder didnt size that well either. So even if they did a J load the duct work would still be wrong. The proper thing to do would be to install the correct size unit, plus air balances the ducts. Now I normally would say ok lets do these corrections but Im not sure I can really trust the ac installer with their current track record.

So the question is where I push. Do I push for the correct size system and having the duct work air balanced? Or do I live with the 5 ton and have the R/A fixed and dip switches changed. From a Homeowner perspective Im not sure where I can push before I hit the flaming wall of go to hell.
Thanks

Bluelogic

Blue - You might give some more info about your situation. You talk about a builder and then you talk about a replacement system and "new construction" standards.

Hard to figure all the parties and the situation.

I might get an independent Manual J to know where to start. Here in NC, a Man J is mandatory on new construction. Why you would have a mandated sealing of ducts and no mandated Man J is pretty stupid but then when CA comes up, that seems to happen.

Was this a renovation? Did you add new ductwork?

I mean doubling the size of a unit is pretty stupid and I don't really know what your HVAC people were thinking. Do you have a permit board and licensing board to go to for leverage? Did these HVAC people pull a permit? No way would any of this pass an inspection in NC.

David,
There is only one party the ac installer. The duct sealing they said fell under new construction standards, but HERS did not really test it, because my home was consider part of a sampling group were they dont have to test it.

This is a renovation. I was going to upgrade the attic based ac and heater because the previous 2.5 ton compressor would run for hours and then it finally started overheating. At the time I was told that to air seal the attic and replace the insulation to bury the duct work I needed to have the ac upgrades done first.

Im guessing here that the ac installer figured I needed 3 tons and a 5 ton would then always run in low mode and move up to the higher mode when in demand. The book says the compressor runs at 70% or (3.5 tons) in stage one. When we did the static pressure test, CFM, and leakage test the system was running in stage 2.

Yes the AC installer did pull a permit and I had a review done by my city. The AC installer is also a Trane and Lennox authorized dealer per the companies websites.

Thanks
Bluelogic

David,

The ductwork is existing they didn't touch it. The home came with it and it was sized to 2.5 tons, but not air balanced. Some of the bathrooms can get cold.

Thanks
Bluelogic

so you are in california..always good to know what climate.

Pardon the cutting & pasting but it is the only way I can
address these particulars:
'The R/A could probably be fixed by either making it 25 or by installing a return in each room. Increasing the return to 25 is something they are open to so far.'

Of course they want to just increase R/A size rather than adding R/A per room..less work. In my climate/area we have central R/A..so I'll leave it to someone else to comment on that, However I would think that having the ducts sized properly & correct amount of R/A would be a better investment.

'I like the return in each room instead because the return is in the main hallway on the top floor and it causing massive negative pressure that it is sucking air from my can lights from the attic.'

They make inserts for IC recessed lights to make them air tight. This should be done regardless of any other modifications. get brand and model number from inside recessed cans and go online. at mfg's site search for ICAT
and it should bring up all the inserts and trims. you want
a housing that goes inside the can light..not just the trim.
the purpose is to seal the holes in the housing of the IC
can that allow the attic air and voc's to enter the house.

'The company is blaming the home builder for not creating proper duct size and insists that is not their fault.'

HVAC company says builder resopnsible for duct sizing??
never heard of that. HVAC or independent for load calcs
and duct sizing & layout.

'So far from talking to them it seems they dont have an idea what a J load is. The owner installed my system and he insists that I need a 5 ton no matter what.'

rule of thumb sizing from bubba hvac..got that already.

'My BPI auditor said if they need a Manual J and Manual D he would do it as my consultant.'

there is your independent load calc, now you just have to get hvac company to use it..that could be another battle as they insist that 5 tons is needed, you may have to shop for
a new company..I've had load calcs that hvac company wanted me to warrenty if homeowner's house got hot in the summer
when they had 20+ people over and kids in and out of house.
its just the mentality of bubba.
do you trust them to size r/a and change ducts..once they get your unit to run in low speed?

you probably will hit that flaming wall..that is why I tried
to break it down into workable solutions that the company will accept. I know its a pita to have to cater to them...but if they work pissed off..you got a bigger mess than ever before. not fair, but itrw..just how it is.

for me the bottom line would be the replacement of ductwork and proper sizing of R/A. how can your system heat and cool if the ducts can't move the air. more air flow is needed for the system that moves more air. instead of 1000 cfm of air you now have 2000 cfm to be moved..the ducts can't do it.I'm basing cfm on 2.5 tons in first post as opposed to 3 tons in later post.3 tons would be 1200 cfm

that you are stuck in high speed is showing you all the problems. if the system were in low speed the problems would be less..until it switched to high speed.
duct sizing still needs to be changed.

as it is difficult to envision...what is the approx sq ft
of upstairs living space?
you said:At the time I was told that to air seal the attic..
what method of air sealing?

lots of questions..but we only know what you tell us.
and as you post more info comes available.
go back and answer questions..as more info helps.

I'm not real clear on duct leakage..was it tested or not?
our standard her in La. is 5%..10% is what most hvac companies achieve after me teaching them where and how to seal.

best of luck,.

Energy Rater LA,

Duct sizing would be good but I still have the problem the unit is oversized. I can probably get them to increase the R/A. From reading an oversized return in not the end of the world.

I read the manual on why it is stuck on high speed; they didnt remove the jumper between the high and low set in the furnace. Yea why does the home owner need to read that?

Square feet is 2100 two story with all bedrooms upstairs. About 1000 square feet upstairs.

Air sealing by having all the old insulation removed and foamed sealed then reinsulated. My attic is currently R-13.

Duct leakage was not tested by HERS but was tested my BPI auditor. It was 9%.

Thanks

Bluelogic

All,

Ok, I touchbased with the company owner again today and he would like to personally come and do a Manual J and Manual D, next Monday. He said he would check the stage one and stage two compressors issue and would like to review the BPI auditor findings.

The direction this is going from asking him what he felt was the best option he mention the following.

1. Having a Manual J and Manual D done.
2. Increasing the return to 25. I did not mention my idea of a return in each room yet.
3. Correcting the staging issue.
4. Sizing the ductwork.
5. If the system CFM exceeds the max needed for the house instead of dumping the extra CFM he would like to configure the variable multiple blower position high to the correct CFM for the house.

I let everyone know were this is going when I have an update next week. If anything I am so glad, I had the BPI audit done. I would have never figured these problems existed or knew to look. I tell all my friends now that want to upgrade their homes for the $1500 tax credit to get a BPI auditor. It was the best money I ever spent on my house.

Thanks
Bluelogic

But you don't NEED 5 tons,
and you trust him to do load calcs & duct sizing?
I'd be leary of that. let the bpi guy do calcs & sizing
of ducts.

5. If the system CFM exceeds the max needed for the house instead of dumping the extra CFM he would like to configure the variable multiple blower position high to the correct CFM for the house.

Here - in my humid climate lower speed removes more humidity.
Everywhere - lower speed is more efficient.
and when he corrects the high/low speed issue
you still want you ducts to handle the times when
your load requires high speed.

I don't know how to say it differently..as this is my
3rd attempt to phrase it in an understandable to you fashion.

Thanks for answering the questions!

And tell everyone that energy raters & BPI folks
show you where the house/hvac issues are,
Tax credit is ok...but lowering the cost of living
in the home is the goal.I've seen ho's lose their homes
because they couldn't afford to live there.

What type of utility rates do you pay in Ca?

I'm lucky...8 cents per kwh with my provider
which is a co-op. (owned by the customers)

I've seen a lot of folks build/remodel/retrofit and still can't afford the utility costs, hot and cold spots
lack of thermal and air barriers....

make the house tight and ventilate right!!!

best of luck..

didn't mean to come across that way,
day 2 on the patch...to quit smoking.
what to non-smokers
do with their hands??
sincerely,
best of luck.

Energy Rater La,

I would have my auditor review the findings. I heard one of the common things is to change the indoor temp to 75 instead of 78. As a side note the auditor did mention that I have eight 5 x 7 East facing windows.

I dont live in a humid environment. With the AC off right now and the windows open the humidity is 34%.

I pay the highest rate in the country through PG&E =) 13.3 cents per KWH on average.

My house is air tight that the auditor recommended mechanical vent, such as turning on a bathroom fan. Im on a slab no crawlspace.

My retrofit plan was to upgrade the ac/heater the old compressor overheated on the 2.5 ton. Have the attic insulation removed. Have the attic air sealed and the can lights put in a box. Have the ac ductwork buried in insulation, up to R-60 including the rest of the attic. Have a whole house fan installed for the some nights. I live near the delta so I get some nice winds. Have a radiant barrier installed on top of the R-60. Radiant barrier my garage door.

Thanks

Bluelogic

A couple of thoughts.

13 cents is not that bad. I was thinking you might be 30 cents....

R-60 in the attic. In CA? Where are you again? R-60 would be generally be a waste in most of CA. Even at R-30, your solar gain through the windows might be 10 times the roof heat gain. A radiant barrier with R-60 might literally save you $5 a year. But I don't know where you live.

In my neck of the woods - where today is 97 and more humid than you, my solar gain through low-e windows is far more than roof/attic gain. The latent heat from the humans is closer to the roof attic gain. I have r-40 (and a radiant barrier) but that is primarily for the winter, not the summer.

Is your retrofit plan based on energy auditor recs? Because I can't imagine that attic plan makes financial sense. I mean - replacing your windows if they are older. Seer 18 equipment. Heck - solar panels to generate electricity may have a faster payback (with incentives) than r-60 and a radiant barrier (now - again, CA is a big place and I don't know where you live). And if you don't have proper placement for the solar panels - the issue is moot.

I'm going to throw a couple things out there for you to think about. The delta T (difference between outside temp and inside temp) in the summer is low in most parts of the world. Mostly, there is no delta T at night. In the hottest parts of the world, the delta T is 30 degrees and even that isn't average (maybe death valley). Now go to winter, the delta T is often 80 degrees in parts of the US (-10 outside). Now maybe R-60 makes sense. But when you are looking at delta Ts in the 20 degree range for day and zero at night, upgrading the R value is not that helpful.

Now - I'm sure that I'll get the argument that attics are often hotter than ambient. That is true, but even still, going to R-60 is not the answer.

For my energy audit, going from r-30 to r-40 saved $20 a year. It cost $250 and I did it (new construction). In NC, probably $16 of that $20 was winter heating. So with a milder winter, that savings literally could be just $10. And this is on a 4000 sq foot house. At your house size, it might be $5. When you go to R-60, it might be $7. Now, it might be more since you pay a tick more for electricity but these are the numbers you should be thinking about.

Give some fiberglass to the homeless if you are concerned about environmental issues. And think of this, if you are taking away fiberglass from somebody who really needs it (by driving up cost), you might actually be harming the environment. You have to chase the dollars, everything else is counterproductive.....

Sorry for the rant. You do know that the assumption is that anything CA is just wackedout. My father lives in Berkeley - wacked!!

David,
13 cents is the average. Im usually in the high PG&E Tiers 3-4. Im in zone 12 and Title 24 requires R-38 to R-49. I have R-13 right now; however, there is an additional consideration. My attic covers the entire second floor and all my ductwork is belt attached to the roof area in the attic and the furnace is in there also. This is unconditioned space that regularly reaches over 100. It would make sense to take the ductwork down and bury it under the new insulation.

Thanks
Bluelogic

Ok - I don't think Zone 12 exists. Honolulu is Zone 11 which means 40 (or 45) is the low. Now maybe you are talking different zoning systems but most would assume USDA zones.

Title 24 of course is a bit extreme and written by extremists. But then again, I'm just a conservative that drives a Civic hybrid.

In humid areas, covering the ductwork with insulation is an absolute no-no. Here code is R-8 on ductwork and it is considered to be about 10% as important as the attic/roof insulation. I don't think anything greater than r-8 exists for residential construction so thinking that you need anything more than that is .... overkill.

Our duct loss is considered about 10% of energy costs. That is with 130 degree attics and R-8 insulation. That 10% is probably 90% leakage so just little r-8 gets you down to 1% of costs.

I'm just saying that covering the ducts with insulation is not all that important and helpful. 1% is maybe all that you are chasing.

Aren't we talking about a system that is 2 times what it should be and you are going to Montana level attic insulation?

So I'll go back to original question - where are you since USDA zone 12 does not exist in the continental US.

Ok - so you are talking CA zone 12

Title 24 is crazy like I said. So you get some cold temps but nothing real. I don't understand the difference between C and D but R29 in walls is crazy.

Good luck with all that. Here we have almost the same number of CDD and HDD and code is R-13 in walls and R-30 in attic. I think R-40 in the attic is not a bad idea and R-19 in walls is pretty nice. After that you are chasing $5-$10 a year in costs.

You have a code that is overkill - going over that is even more overkill.

David,

The idea of going over was to bury the flex duct that is only r-4.

Bluelogic

Bluelogic,

I'm an average Joe homeowner, who happens to be very meticulous about how much energy I use, how insulation and RBs work, as I've been upgrading efficiency for several years now. I live in Fresno -- hot arid, no humidity to speak of except for those few storms that swing in for a few days to bring our rain around 10" /yr (this year was a fluke).

If your climate is like mine, you are on-track with the idea of placing the ductwork under the insulation and THEN putting a radiant barrier on top. People who live with cold focus on totally different benefits of the RB/insulation. I think the R39+ reqs are crazy when you can totally seal off the conditioned living space with a) closing up leaks, b) putting average insulation (even ~R19), c) putting a radiant barrier on top of all the insulation (and ducting) and any interior walls that may be exposed inside the attic (vaulted ceilings usually). But oh well... R60 in attic is way overkill imho.

The RB will increase the temps in your attic during the hot of the day. That is so against "the norm" what people will advise you. If your roof hasn't been replaced lately, it's likely you'll need more ventilation as 10yr code won't be adequate.

My attic temps were already 130+ BEFORE the RB and that heat went directly into the insulation --> which stayed there a long time into the night transferring into interior, which is why I needed to run the AC all the way into the AM hours before.

Be sure to RB the plenum too, otherwise radiant heat transfer will penetrate into the ducting via that route after you install the RB.

Here are my before/after pics:

My first question (in bold) got trimmed somehow.

So what happened with your HVAC situation and the later RB upgrade?
Do you mind sharing how it worked out and whether there were any savings?

cebury - WOW. How much did that help? And why not radiant barrier the roof?

I am looking to improve things and I would consider that if it helped significantly. I am mixed humid so it is a different world. But, I don't see a downside to radiant barrier on ductwork and I actually have some that I added that has a RB. I also have an RB ceiling.

Any idea why Title 24 goes so high on attic insulation. I mean the average existing stock in CA is probably r-13 - would it make more sense to mandate updates on existing stock? Even to the point where you have government pay for it?

It is a pet peeve of mine when government goes so overboard on new construction requirements when the old stuff is such low hanging fruit. I am building in a rainy area and am required to have gravel driveway and run the gutter downspouts to an underground reservoir to prevent runoff ... meanwhile most of the existing stock has concrete driveways with zero runoff protection. Admittedly - removing concrete drives is not easy but maybe some gravel trenches.

how are you going to keep the radiant barrier's reflectivity?
sutdies show that dust build up reduces rb performance
by half in 5 years.

is that new ductwork or old wrapped with rb mateterial?

Ca. climate allows things we absolutely can not do in
hot/humid climates. buring ductwork in insulation causes ducts to condensate
adding an additonal vapor barrier over vb of ductwork causes condnesation between the two vb's.
high humidity causes lots of issues for us.

glad to see this thread is ongoing. looking forward to
reading more.

David,

I live in dry CA and honestly have not done any research on how it affects humid environments so my experience can't offer you much help.

Did it work? It helped reduce my electric usage immediately and the air temp differential from a vent dropped by about 3 degrees immediately. I didn't test much after that, but the before/after differential was done two days apart at the same time of day.

I was keeping my thermostat between 81 and 83 (damn sweaty hot) and still had a $400/mo pge bill (~1700kwh) and after the RB I kept it at 77 and the bills were between 10 and 20% lower. The bills compared year-to-year were so much lower over 12mo period (20%?) that the utility gave me some kind of automatic refund.

I bought my stuff from Horizon (savenrg.com). They are in Phoenix AZ where the climate is a bit worse than mine, but similar. They aren't a flashy company, obvious from their site, but their material made so much sense when I confirmed from other sources. It's not cheap. The owner also helped teach me the DIY w/duct sealing: making sure all joints are tight (ties/metal straps), lathering on tons of mastic on them, and applying metal backed tape where needed.

Dust is the #1 killer of a radiant barrier. Their site explains it and how multiple layers of reflectivity, when separated adequately (scrim), keep the RB working even when dusty on the top layer. The RB on the floor, above the insulation, is triple layer. The ducts are wrapped with their ducting RB which is double layer and I put the triple layer on the top-parts where the dust might collect.

Either way, I'm not taking chances as I'm having my roof replaced and afterward I'm going to cleanup & dust where it's easy to do so. After the 15 months I went back up to check out dust and it was very minimal, except directly under the dormer vents where a handful of smaller leaves/dirt had dropped.

Ducting: That's existing flex ducting (r4/5 don't recall) wrapped w/multi-layer RB.

RB under Roof I'm not sure it will help all that much to put RB under the roof when it's already on the attic floor + ducting like mine. Their site also talks about this. IMO I'd be creating an oven situation, but in reality I don't know if it matters. I currently have shake roof w/stick frame so it slightly breathes there and through the ventilation at night. However, once it goes to OSB w/composite shingles, I'm relying on the vents anyway.

The roofing salesmen say "sure it helps, anytime you can prevent heat from entering the attic in the first place is good" as they try to sell the OSB w/tiny bit of foil on the bottom of it. I don't know if that works w/out creating conductive heat transfer that then radiates in the attic.

As far as whacky CA rules, yeah no kidding. I honestly think in certain parts of CA they should've left the R alone and just suggested RB properly installed.

I was hoping bluelogic would've been subscribed to his original thread and could tell us what happened with his project.