Do I need to have this redone? Should I? Attic Installation LG Low Static Ducted Heat Pump

centralMA

Should I try to have this redone? Unconditioned, vented attic Installation of LG Low Static Ducted Heat Pump

I have two areas of concern. One is the impact of excessive crimping/smushing on air flow. That’s what I thought when I saw it, because I thought it would look a lot neater. After reading more about it, I learned there is a second concern based on all the contact the ducts are making with different surfaces, which is about condensation.

Reading from the “Support at Intervals for Flex Ducts” https://basc.pnnl.gov/resource-guides/support-intervals-flex-ducts#edit-group-retrofit, it says:

Additions: If new flex duct is added to an existing home, either as part of an addition or an equipment upgrade, ensure that the flex duct is installed in runs that are as short, straight, and direct as possible, and properly support the duct through the use of hangers or stands as noted in the Description tab.

It seems like the air flow restrictions would have consequences on the air handler motor if the external static pressure is too high. I have inquired with the installers about if they did a static pressure test and what the results were.

On the condensation, I am concerned from this: https://basc.pnnl.gov/resource-guides/support-intervals-flex-ducts#edit-group-climate I am not sure anyone worries about it here though in our 5A cool-humid climate. I don't know if it is a problem or not, or how much of a problem it is.

Would you (should I) worry about condensation and moisture problems from having cooling ducts in an unconditioned attic resting on loose fill insulation and crossing over and laying on each other and with crimping around corners? Or is that something people worry about at Building America Solutions, but unnecessarily so?

yellowdog

I'd be more concerned about all of the insulation that they pushed aside and didn't put back. But its a hack job nonetheless.

centralMA

I looked over the ADA Fifth Edition Flexible Duct Performance & Installation Standards. That’s a place where the issues with the layout are really highlighted.

centralMA

yellowdog said:

I'd be more concerned about all of the insulation that they pushed aside and didn't put back. But its a hack job nonetheless.

Yeah, I was concerned about the insulation not being put back as well.

pecmsg

That’s too much flex and not installed properly. Safe bet that static pressure is past the maximum 

pecmsg

Questionable drain as well

Jamie Hall

And we wonder why forced air and ducted heap pumps get a bad rap. I hope it was cheap.

centralMA

Haha Not cheap

Is it within reason to ask them to redo in accordance with ADC fifth edition standards?

pecmsg

You can ask but that should have been read and followed the 1 st time. 

Have they been paid?

EBEBRATT-Ed

The air handler should be hung from the rafters. It should have a auxillary drain pan under it. The ductwork should be all metal duct with flex only used for the branches. The branches should be 6-8" maximum. It's a total mess.

Hot_water_fan

Let’s see the static test results first. 

pecmsg

The ones the installing contractor does or the real ones?

centralMA

Yes, they have been paid. Yes I am very curious about the static test results. I'll post them here when I get the data!
And yes, I too have some concerns about relying on them for the testing but it is what it is.

pecmsg

Then hire a different contractor and get it verified!

ChrisJ

A very smart person told me no more than 5 feet of flex duct and it needs to be pulled tight.  No sharp turns either they should be done using elbows.

5 feet of flex allowed is good for sound attenuation.

Id want that all redone.

EBEBRATT-Ed

The general rule is the flex comes in boxes 25' long. You cut it in 3 pieces so 8' is the maximum length. The corrugation in the flex reduce the air flow

centralMA

pecmsg said:

Then hire a different contractor and get it verified!

I really liked the idea of a third party static pressure test. However, I realized that the test involves some drilling. That drilling by a third party HVAC company would likely waive my warranty and free the original company from their responsibilities. So I decided against it.
Thanks for the responses everyone. This feedback is helpful for when I talk to the tech next week and hopefully they take the opportunity to improve the work.

pecmsg

BS
No way 2) 1/4” holes can void warranty. You have ever right to have there findings verified!

centralMA

Hi, I thought I'd post an update.

The Quality Control person from the company came out to the house.

#1 He identified that the return is too small and needs to be sized up from 10” to 12”.

#2 They are going to redo the drain piping.

#3 He agreed the ducts were unnecessarily long and loopy

He did NOT think that the general design and smooshing/bending was a problem. His reasoning: Some of the insulation is being smooshed but none of the inner cores are being impacted at any point. So at no point are the ducts actually being compressed/restricted from the overlapping or resting on the ground or turns and stuff.

He does say the runs are a bit tangled and loose and need to be organized better and tighter. He is estimating 2 hours for one technician.

I think it might be the case that they are not familiar with the low-static requirements (as they should be if installing).

Because they offered to rework the ductwork, it didn’t make sense to have them test the external static pressure before that.

I get what you are saying about a third party Static Pressure Test. The thing is, I've talked to 4 different HVAC companies/people and none of them wanted to do the test while under someone else’s warranty (1 year warranty from the install company). They advised me not to do it. So I think I at least need to go through the installation company first, and then if the test is fishy, figure out a third party.

Is the external static pressure test easy enough to do with this air handler? From looking at information online it seems like the test is done most simply when there is some rigid ductwork off the plenum, which mine doesn’t have. It seems potentially less straightforward on my setup and if the company isn’t used to doing it, they might struggle with it. Just another thing I am anticipating making this situation more complicated.

The Quality Control guy who came out was pretty comfortable criticizing the work that was done, the installer, and the installer’s manager. That gave me confidence. So I am pretty confident the problem remaining about his lack of concern about the external static pressure would be out of ignorance. That doesn’t mean I still don’t have an issue though. Ignorance now, but could very well turn into denial…

Before the QC guy left I again expressed my concern about the static pressure and reiterated my desire to have a static pressure test done. He half-heartedly agreed to it saying that he didn't think they would need to because it wouldn’t be a problem after improvements are made. I left it there for the time being.

I am almost ready to take the improvements they are offering and be done with it. But I figure I should press on. I mean, I don’t want this unit to break down in 5 years instead of 10 or whatever the lifespan should be.

My plan right now is to write them an email reiterating that I want the external static pressure test done. And why, with screenshots of the product specs and warranty card. And see if I can get in writing a commitment from them to ensure the static pressure is within LGs limits before they can call the job completed.

e.g. "I’m concerned that if the static pressure is too high, the HVAC system has to work too hard to push the air. The external static pressure test would be a great way to verify there won’t be fan problems down the road. Can we make sure to definitely do the test? I’m concerned about the potential impact on the equipment."

Thanks for your input folks.
Sincerely

pecmsg

It nice the contractor is addressing it. 

Post pictures when there done

pedmec

if your in Massachusetts that installation is wrong. you can't have more than 6"of flex duct from the plenum to the register. a permit should have been pulled. a manual d and manual j should have been submitted to the inspector. r value for unconditioned space is r-8. this is a bad job and should be started over. no drain pan is really an indication that they probably are a hack company. these are they type of installs that necessitated the creation of a sheet metal board and licensing. too many jobs are like this. whether you like the idea of a sheet metal board and lisencing is a different argument .

centralMA

Hi, thanks for the feedback.

Yes, I am in Massachusetts. I have searched for building codes. This is what I found: https://codes.iccsafe.org/content/IRC2015P3/chapter-16-duct-systems

I do not believe the code gets into allowable flex duct length.

It does say:
Duct systems serving heating, cooling and ventilation equipment shall be installed in accordance with the provisions of this section and ACCA Manual D, the appliance manufacturer’s installation instructions or other approved methods.

I’m not sure if ACCA Manual D specifies maximum flex duct length. I do believe it generally demonstrates a lot of the problems with the install.

A permit was pulled. I doubt a Manual D was submitted. A Manual J was done. Inspector already approved the work and closed the permit. He was generally not concerned with code or work quality.

I think it is sitting over a drain pan? Someone pointed out that they left it with loose insulation in it, which could be a problem. They did commit to redoing the draining.

I actually thought I was hiring the best company I was able to find.

RPK

You should 100% insist on a static pressure test! Any reputable contractor would measure static pressure as a basic step in startup testing. It is not technically challenging in any way. The instrumentation is not expensive or complicated to use. You could do it yourself if you bought a digital manometer.

BTW, is there a filter rack somewhere in there and is it properly sized? An incorrectly sized filter could aggravate excessive static pressure issues.

pedmec

Was the inspector blind. i have had town inspectors make other contractors rip out newly installed systems due to incorrect heat gain calculations. never mind shoddy work. blow door test are required. the 6' rule is there. ill find it and show it to you. maybe ill ask my boss where it is as he sits on the state board. It is also a better installation practice

centralMA

Thanks for the static pressure thoughts. There is a basic filter in the return grill. I do not believe there is another filter. No one told me there was; I think I even asked about it.

Thanks pedmec. The Inspector was bad. He himself told me that there is another inspector (retired) that had prior HVAC experience that was a stickler. He made installers redo work if there were issues and put returns in every room. My inspector told me he doesn’t make people follow the code. I showed him all of the code documents and all of the standards (ACCA, ADC, SMACNA) referenced by the code documents that I had printed out. I pointed out aspects of the codes and referenced material and the pictures about how the code said it should be installed. The inspector did not commend me on my interest and enthusiasm for building code, or tell me that the municipality was lucky to have so interested a citizen.

Based on everything I have read and been told, yes, shorter flex runs certainly (at the very least!) seem to be best practice! The contract states All work will be completed in a workmanlike manner according to standard practices. So that is what I am looking to hold them to. I’m not looking for perfect, just decent/acceptable!

A long shot, but if there is anyone here who could do a third party evaluation in Central MA or knows someone who would, I would be interested in having that!

ChrisJ

centralMA said:

Thanks for the static pressure thoughts. There is a basic filter in the return grill. I do not believe there is another filter. No one told me there was; I think I even asked about it.

Thanks pedmec. The Inspector was bad. He himself told me that there is another inspector (retired) that had prior HVAC experience that was a stickler. He made installers redo work if there were issues and put returns in every room. My inspector told me he doesn’t make people follow the code. I showed him all of the code documents and all of the standards (ACCA, ADC, SMACNA) referenced by the code documents that I had printed out. I pointed out aspects of the codes and referenced material and the pictures about how the code said it should be installed. The inspector did not commend me on my interest and enthusiasm for building code, or tell me that the municipality was lucky to have so interested a citizen.

Based on everything I have read and been told, yes, shorter flex runs certainly (at the very least!) seem to be best practice! The contract states All work will be completed in a workmanlike manner according to standard practices. So that is what I am looking to hold them to. I’m not looking for perfect, just decent/acceptable!

A long shot, but if there is anyone here who could do a third party evaluation in Central MA or knows someone who would, I would be interested in having that!

Besides being way too long and sloppy with sharp turns there's a whole lot else going on there.

For example...





This is why besides no sharp turns and being kept short it must always be stretched out fully.
It's not optional.

KC_Jones

centralMA said:

Thanks for the static pressure thoughts. There is a basic filter in the return grill. I do not believe there is another filter. No one told me there was; I think I even asked about it.

Thanks pedmec. The Inspector was bad. He himself told me that there is another inspector (retired) that had prior HVAC experience that was a stickler. He made installers redo work if there were issues and put returns in every room. My inspector told me he doesn’t make people follow the code. I showed him all of the code documents and all of the standards (ACCA, ADC, SMACNA) referenced by the code documents that I had printed out. I pointed out aspects of the codes and referenced material and the pictures about how the code said it should be installed. The inspector did not commend me on my interest and enthusiasm for building code, or tell me that the municipality was lucky to have so interested a citizen.

Based on everything I have read and been told, yes, shorter flex runs certainly (at the very least!) seem to be best practice! The contract states All work will be completed in a workmanlike manner according to standard practices. So that is what I am looking to hold them to. I’m not looking for perfect, just decent/acceptable!

A long shot, but if there is anyone here who could do a third party evaluation in Central MA or knows someone who would, I would be interested in having that!

People can hate me for this, but I don't care, I'm tired of contractors stealing from homeowners and now inspectors are getting in on the action apparently.

The inspectors serve at your pleasure, not the contractors doing crap work. This situation is 100% unacceptable. At this point I'd be contacting the town and letting them know your install failed inspection by any reasonable standard and yet their inspector passed it, and admitted to you they do not enforce code. If they do nothing, honestly, I'd be contacting an attorney. You paid for something you did not get. The contractors and inspectors don't own you, as much as they apparently feel they do. Yes that's harsh, but it's obviously justified here. That install is crap.

worldclasshvac

Complete hack install.  I see this all the time.  Unit needs to be suspended as the access for most repairs is underneath the unit.  All ducts should be hard piped sheet metal with flex the last few feet to the register box.  Id bet nothing is sealed well or taped/mastic.  This is a slam it in fast and it works were done type of install

pecmsg

worldclasshvac said:

Complete hack install.  I see this all the time.  Unit needs to be suspended as the access for most repairs is underneath the unit.  All ducts should be hard piped sheet metal with flex the last few feet to the register box.  Id bet nothing is sealed well or taped/mastic.  This is a slam it in fast and it works were done type of install

Agreed and I’ll add where’s the line set loop

pedmec

I think its funny that they sent out a quality control guy and he was ok with most of the install. if there was ever a duct job that needed to be ripped out and started from scratch its this one. Honestly though I think you're gonna get the run around. If he didn't think that the flex was an issue then he is just as bad as the installers. He probably trained them.

I know this sucks but i would ask for your money back and get another company. This company is not going to do you right. They should own this and they are not. The first indication is that they are not going to do the right thing.

And forget about going after the inspector. In Massachusetts the inspector cannot be held liabel for missing a code violation. it's on the books. i'm sure if you got a good attorney you could get him on some how but if you could go after inspectors in the state you probably wouldn't have any inspectors

centralMA

Hi,

This stinks.

I think what you all are saying is strongly backed up by authoritative sources and standards.
At this point, this Friday, they are coming back to do whatever small changes they want to do. I will try to get them to do the static pressure test that day (for an objective measure of at least that concern). If for whatever reason that doesn’t happen, I already have an appointment for them to come back and do the test the following Friday.

I’ve read up on the external static pressure test so I’m not totally ignorant about it and I’ll be with them when they do it.

I appreciate the info and advice y’all.

centralMA

Photo of techs running an external static pressure test using a manometer. The tube connected to the right side (above the plus sign) is supposed to be connected to a probe on the supply side, isn’t it? They connected it to a probe on the return side. The negative side tube is on the supply side. Is positive-to-supply a requirement for proper testing? 

Someone else is coming out to run the test again this Friday. The company wasn’t necessarily expecting these techs to have to run this test. I just want to make sure that my assessment that they didn’t do it right last week is correct. 

Thanks 

centralMA

Just updating. They came back today and this is what they found. .29 on the supply. .07 (edited!) on the return. combined .36 in wg.
Tech insisted that combined equals .22 (29-7) not .36 (29+7). I insisted that for "Maximum External Static Pressure" the relevant number is .36 in wg. He called someone else who confirmed his POV but he is going to ask someone else and look into it further. Furthermore, he doesn't think the external static pressure matters. He says the air flow CFMs are good and that is what they and thousands of people design around, not static pressure. I am working on this still... I just wanted to give an update for people who have been helping me. I am still working on this...

ChrisJ

centralMA said:

Just updating. They came back today and this is what they found. .29 on the supply. .7 on the return combined .36 in wg.
Tech insisted that combined equals .22 (29-7) not .36 (29+7). I insisted that for "Maximum External Static Pressure" the relevant number is .36 in wg. He called someone else who confirmed his POV but he is going to ask someone else and look into it further. Furthermore, he doesn't think the external static pressure matters. He says the air flow CFMs are good and that is what they and thousands of people design around, not static pressure. I am working on this still... I just wanted to give an update for people who have been helping me. I am still working on this...

Pretty sure that equals 0.99" or, let's call it 1"WC.
I'm far from an expert, but it's my understanding that's double what most modern residential air handlers are designed around.


I'm sorry you're dealing with this.

worldclasshvac

Your TES in that pic is .65 in wc.  Those low static units want less then half that,........you can get anything to run with some tweaking, what ppl need to realize is that motors, fans, etc will burn out faster and premature lifespans are the result of poor installs

ChrisJ

My mistake I took 0.7 as being the supply side rather than the total.  I didn't look at the meter at all.

I'm sorry. 

pecmsg

centralMA said:

Just updating. They came back today and this is what they found. .29 on the supply. .7 on the return combined .36 in wg.
Tech insisted that combined equals .22 (29-7) not .36 (29+7). I insisted that for "Maximum External Static Pressure" the relevant number is .36 in wg. He called someone else who confirmed his POV but he is going to ask someone else and look into it further. Furthermore, he doesn't think the external static pressure matters. He says the air flow CFMs are good and that is what they and thousands of people design around, not static pressure. I am working on this still... I just wanted to give an update for people who have been helping me. I am still working on this...

And there Wrong!

https://calcerts.zendesk.com/hc/en-us/articles/360051851293-Total-External-Static-Pressure-07-15-2020

https://hvacrschool.com/total-external-static-pressure-tesp-a-basic-review/

pedmec

is that .7 wc or .07. That is going to make a huge difference

centralMA

Hi,

here are two pictures. Yes, I totally messed up and wrote .7 instead of .07 for the return. My bad! There is a little arrow on the display jumping from pointing to P2 to P1 in the two photos.

https://hvacrschool.com/total-external-static-pressure-tesp-a-basic-review/
I actually printed out this document and gave it to them to read over.

The tech said that the HVAC company warranty covers the parts for 10 years so that if the blower fan or other parts fail, they will replace it free of charge to me. He said they will put that in writing again. My girlfriend reminded me last night that besides the parts failing I was also concerned about energy efficiency of electrical usage due to static pressure being too high. This is also mentioned in the CalCERTS document you posted pecmsg (thanks for that doc).

Apparently our filter wasn't totally clean. I have since replaced it. I understand that can impact the ESP results. That is annoying as it means they might have to do this again...

The tech is going to the supplier to discuss what I am bringing up. Hopefully they are in for a rude awakening that they have been doing things wrong for years, but I am not holding my breathe. Like I said, I am still working on them...

Many thanks y'all

ChrisJ

centralMA said:

Hi,

here are two pictures. Yes, I totally messed up and wrote .7 instead of .07 for the return. My bad! There is a little arrow on the display jumping from pointing to P2 to P1 in the two photos.

https://hvacrschool.com/total-external-static-pressure-tesp-a-basic-review/
I actually printed out this document and gave it to them to read over.

The tech said that the HVAC company warranty covers the parts for 10 years so that if the blower fan or other parts fail, they will replace it free of charge to me. He said they will put that in writing again. My girlfriend reminded me last night that besides the parts failing I was also concerned about energy efficiency of electrical usage due to static pressure being too high. This is also mentioned in the CalCERTS document you posted pecmsg (thanks for that doc).

Apparently our filter wasn't totally clean. I have since replaced it. I understand that can impact the ESP results. That is annoying as it means they might have to do this again...

The tech is going to the supplier to discuss what I am bringing up. Hopefully they are in for a rude awakening that they have been doing things wrong for years, but I am not holding my breathe. Like I said, I am still working on them...

Many thanks y'all

How is their warranty handled?

I'm NOT a contractor, just a homeowner so don't get too concerned with my question, but I thought most of the time only parts were covered and not labor?

centralMA

ChrisJ said:

How is their warranty handled? I'm NOT a contractor, just a homeowner so don't get too concerned with my question, but I thought most of the time only parts were covered and not labor?

Yeah I was confused by this claim from the tech. I haven’t gone back to read over all the warranty stuff yet. But he was saying that they would put something new in writing for me to cover parts and labor for the motor. 

Side note: my further reading on relationship between static pressure and ECM motors makes me think that this company going off of  CFM is maybe attributable to that being more rational when using the more traditional PSC motors. Because on a PSC motor if static pressure is too high there will be a CFM reduction. Whereas an ECM can compensate to maintain CFM. At cost to equipment and energy use.  And these people are still applying PSC logic.  

Or maybe this theory doesn’t hold water  lol