New Home HVAC System

/ New Home HVAC System #101  
To ensure we're on the same page, what are you proposing for residential use for home heating and cooling, not commercial use?

To some extent, why Geothermal is one of the best sources for HVAC for residential use, but also more expensive than forced air.
i believe we are on the same page. The point i am trying to make is today, you do not necessarily want a ductless system, as you want to exchange the inside air with the outside air. You can do it with a HRV, then you are looking at ducts and you might as well have used a simple air handler with ducts. Commercial buildings are going to demand so many air exchanges an hour. i would think you would want something similar in a new home. In the future slapping a mini split on the wall and not exchanging the air isn't going to get it. For a single server room or simple one room addition as a band aid, yes. So, yes a residential house with a geo unit heat and chilling water would get it. I do believe a vrf would get it too. I am not that familiar. Then you fish pex water line through. Use horizonal chilled case coils and basically you have one unit and some pumps. I believe you can get the VRF to the same thing, but it is more complicated.
When the outlaw's come for thanksgiving and one of them has the flu I don't want them giving it to everybody.
You brought up office building. Those same unit that they are using as ground source heat pumps they are using to take the heat out of the air before it leaves the building(air source). Converting it to hot water, then using it to heat the air going into a particular room. This way they can move the heating and cooling around. Say every one in the office just moved into the conference room. Well you wouldn't need to heat the air going in there anymore. That zone would shut off and you would divert the hot water to the office area.
So, how much more is geo(ground source) really than forced air gas heat once you throw in AC? Basically it is the cost of the ground source loop. If you include that it can heat your potable hot water?
 
/ New Home HVAC System #102  
Can't beat radiant heat for the warm feeling.

Agreed. Everyone in the house loves the fireplace. Only prob for me is staying awake. The radiant heat plus blower noise and I may as well have taken a sleeping pill.
 
/ New Home HVAC System #103  
i believe we are on the same page. The point i am trying to make is today, you do not necessarily want a ductless system, as you want to exchange the inside air with the outside air. You can do it with a HRV, then you are looking at ducts and you might as well have used a simple air handler with ducts. Commercial buildings are going to demand so many air exchanges an hour. i would think you would want something similar in a new home. In the future slapping a mini split on the wall and not exchanging the air isn't going to get it. For a single server room or simple one room addition as a band aid, yes. So, yes a residential house with a geo unit heat and chilling water would get it. I do believe a vrf would get it too. I am not that familiar. Then you fish pex water line through. Use horizonal chilled case coils and basically you have one unit and some pumps. I believe you can get the VRF to the same thing, but it is more complicated.
When the outlaw's come for thanksgiving and one of them has the flu I don't want them giving it to everybody.
You brought up office building. Those same unit that they are using as ground source heat pumps they are using to take the heat out of the air before it leaves the building(air source). Converting it to hot water, then using it to heat the air going into a particular room. This way they can move the heating and cooling around. Say every one in the office just moved into the conference room. Well you wouldn't need to heat the air going in there anymore. That zone would shut off and you would divert the hot water to the office area.
So, how much more is geo(ground source) really than forced air gas heat once you throw in AC? Basically it is the cost of the ground source loop. If you include that it can heat your potable hot water?

We are on the same page.

The issue is do you realize how many new homes (built now) bring in outside air via a system designed for that process? It's not high in at least my area. No one wants to spend the money.

Bring in outside air at 40F with low humidity for cooling, no problem. Bring in outside are at 90F with high humidity for cooling, you may have a problem.

Have a 20 ton gas pack or heat pump with economizer, no issue with outside air. Thing is, people don't want to spend the money they need for a HRV/ERV for residential use.

The biggest issue with water source for residential use is loop layout and construction for loop vs air to air. Generally speaking, water source (geo) will run 2 to 3 times more than air to air for that fact alone. Reality is you still need ductwork for both water source and air to air.

As far as ductless, I'm a huge proponent of it, given the right application. Doing a whole home with ductless I'm not a fan of for numerous reasons. Thing is, marketing for ductless manufacturers will try to convince you otherwise.

You have a one story house running on a LP gas furnace with one t-stat in the living room or hallway, with only the owners sleeping at night in a master bedroom? Spend the money on a ductless mini split and you'll see a ROI within 1-3 years depending on price of LP in that area (where heating exceeds cooling load).
 
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/ New Home HVAC System #104  
We are on the same page.

The issue is do you realize how many new homes (built now) bring in outside air via a system designed for that process? It's not high in at least my area. No one wants to spend the money.

Bring in outside air at 40F with low humidity for cooling, no problem. Bring in outside are at 90F with high humidity for cooling, you may have a problem.

Have a 20 ton gas pack or heat pump with economizer, no issue with outside air. Thing is, people don't want to spend the money they need for a HRV/ERV for residential use.


Build tight and ventilate. Seems to be a foreign concept in my area as well. We added the HRV after the fact. I specifically asked our HVAC about the need for one. His response was no due to the volume of home, lots of doors/windows, and an active house with 5 people living there we did not need one and would have plenty of outside air movement. After moving in I started monitoring CO2 levels and we were hitting 1200-1300. Our HVAC guy seemed shocked when I called back to add it. I have it set to run 20 minutes an hour and levels stay around the 620-650 mark. If you stand outside the out-take and smell what is being pumped out of the house you would be a quick believer. Amazing how un-fresh the exhaust air is.
 
/ New Home HVAC System #105  
Build tight and ventilate. Seems to be a foreign concept in my area as well. We added the HRV after the fact. I specifically asked our HVAC about the need for one. His response was no due to the volume of home, lots of doors/windows, and an active house with 5 people living there we did not need one and would have plenty of outside air movement. After moving in I started monitoring CO2 levels and we were hitting 1200-1300. Our HVAC guy seemed shocked when I called back to add it. I have it set to run 20 minutes an hour and levels stay around the 620-650 mark. If you stand outside the out-take and smell what is being pumped out of the house you would be a quick believer. Amazing how un-fresh the exhaust air is.
Yup, then there is the moisture mold issue without one. Build a tight insulated house then poke a hole in it. New Homes if it isn't it will be code. Exchanging the air in the summer gets tricky, cause it brings in a bunch of moisture, then you drive up the humidity level in the house wife turns down the temp because she is having a hot flash, ugh. Then you end up with a humid coldness in the house. I ended up having to add a whole hose dehumidifier. Brought down the humidity in the summer. You bring that humidity down to 40-45% in the summer you can bring the indoor temp up. Works slick should have done it a long time ago.
 
/ New Home HVAC System #106  
Build tight and ventilate. Seems to be a foreign concept in my area as well. We added the HRV after the fact. I specifically asked our HVAC about the need for one. His response was no due to the volume of home, lots of doors/windows, and an active house with 5 people living there we did not need one and would have plenty of outside air movement. After moving in I started monitoring CO2 levels and we were hitting 1200-1300. Our HVAC guy seemed shocked when I called back to add it. I have it set to run 20 minutes an hour and levels stay around the 620-650 mark. If you stand outside the out-take and smell what is being pumped out of the house you would be a quick believer. Amazing how un-fresh the exhaust air is.

One thing about HVAC doing it for a while, no one is an expert on everything.

Didn't know anything about heat pumps until I moved south. Up north, a package unit only goes on a roof. If a guy tells me he's an "expert" in both oil and heat pumps, he's either one of the smartest guys I ever met in my life or he's pulling my leg.

It's apparent your house has a very tight envelope. I'm guessing the owner of your HVAC company who did your work was in his 50's or 60's (or even older), very hands on, but wasn't used to dealing with a ultra tight sealed home with insulation to the max.

The reality is your house is the exception, not the norm.

There is a old school thought that a house should be able to breathe. One thing I know is if it's what a homeowner wants, you give them the pros and cons in your professional opinion if you think they are spending more than they need to, but if they still want it, you give it to them (without hurting the system being installed). Some homeowners think bigger is always better, but that line of thinking can also hurt you, and as a business owner, you need to protect yourself in the proposal).
 
/ New Home HVAC System #107  
Yup, then there is the moisture mold issue without one. Build a tight insulated house then poke a hole in it. New Homes if it isn't it will be code. Exchanging the air in the summer gets tricky, cause it brings in a bunch of moisture, then you drive up the humidity level in the house wife turns down the temp because she is having a hot flash, ugh. Then you end up with a humid coldness in the house. I ended up having to add a whole hose dehumidifier. Brought down the humidity in the summer. You bring that humidity down to 40-45% in the summer you can bring the indoor temp up. Works slick should have done it a long time ago.

The way guys are getting around code in new homes for cookie cutter projects is bringing fresh air through the "fart fan" in the bathoom. Minimal cost.
 
/ New Home HVAC System #108  
It's apparent your house has a very tight envelope. I'm guessing the owner of your HVAC company who did your work was in his 50's or 60's (or even older), very hands on, but wasn't used to dealing with a ultra tight sealed home with insulation to the max.

The reality is your house is the exception, not the norm.

Early 50's. I had the benefit of being my own general contractor so I was here almost every day of the build checking on the subs I hired or was doing some of the work myself. Because of that I had the time to work on air sealing that would not have been practical for a turn-key builder. If there was a gap between two studs that would hold foam or caulk it was sealed up. Spent several days with a borrowed blower door and smoke finding and sealing leaks.
 
/ New Home HVAC System #109  
One thing about HVAC doing it for a while, no one is an expert on everything.

And this is what makes it so hard to know who is "right". My hardest problem as a GC is choosing the right sub to do the job. Even with a set of blue prints from an engineer I have to wade through bids to make sure everyone is bidding the job correctly; and you would be surprised how many don't. It all comes down to your gut feeling and trust in the end.
 
/ New Home HVAC System #112  
And this is what makes it so hard to know who is "right". My hardest problem as a GC is choosing the right sub to do the job. Even with a set of blue prints from an engineer I have to wade through bids to make sure everyone is bidding the job correctly; and you would be surprised how many don't. It all comes down to your gut feeling and trust in the end.

I only laugh because I hope you don't assume that because someone has a PE and title of "Engineer", you assume that what is on the plans is the right equipment for the application with what you're trying to accomplish. That said, I have no doubt a engineer is smarter than myself, but off the record, sometimes I wonder about their common sense.

Per trust, I've found it can only be developed over time. When it comes to choosing a specialty contractor and dealing with new people, just like a homeowner, get multiple bids, talk to the contractor, and don't be afraid to ask questions that may make you look like an idiot (you're not the expert, they are) and see how everyone responds. From my own experience, the better people to deal with who stand behind their word / work are not always the cheapest.
 
/ New Home HVAC System #113  
I ended up having to add a whole hose dehumidifier. Brought down the humidity in the summer. You bring that humidity down to 40-45% in the summer you can bring the indoor temp up. Works slick should have done it a long time ago.

The sales pitch is to us multi stage equipment with a variable speed blower to reduce humidity on not having to use a whole house dehumifier:D

That said, like you, I have a whole house dehumidifier, runs in the summer, keep the t stat to 77F and it feels more comfortable at 40% RH than 72F at 50% RH. I ran a pretty indepth experient in my own home for a deal on my end, and after I got finished with the experiment, my wife told me she was expecting us to keep that dehumidifier because she likes it. Thing to make clear is you won't save money on the electric bill because you're running a higher indoor temp because the dehumidifier does pulls some amps.

Can't speak highly enough about whole house dehumidifiers. Thing is, it's not chump change to tie one into your ductwork (and you can bring in outside air), but we go back to overal up front costs. May sound like a sales pitch, but to a lot of extent, at the end of the day a HVAC contractor sells comfort.

However, take my dad. If he dosen't have it, he doesn't need it. I put in his oil boiler back in the early 90's, and I would feel sorry for anyone who came to his house and tried to "sell" him anything for his home unless it's exactly what he's looking for. He's fine with his 40 year old T-87 t-stat and he don't need anything else! He was born and retired in Pennsylvania, and he'll be the first to tell you he don't need air conditioning (that said, he does appriciate the basement and AC in the car now that he's in NC during the summer time:laughing:)
 
/ New Home HVAC System #115  
Sig knows his hvac... :thumbsup:

Not really. I try to read instructions and surround myself with people who know more than myself.

Decades later, and I'm still asking stupid questions, but I'll at least give myself credit for not being afraid to look like the idiot for asking.
 
/ New Home HVAC System #116  
Not really. I try to read instructions and surround myself with people who know more than myself.

Decades later, and I'm still asking stupid questions, but I'll at least give myself credit for not being afraid to look like the idiot for asking.

A humble man... :thumbsup: I've hired hundreds of mechanical contractors, I know you know your craft. But you are right, always keep learning...
 
/ New Home HVAC System #117  
...and there's no such thing as a dumb question. I still ask them like a 5 year old boy if I think I can learn something.
 
/ New Home HVAC System #118  
I only laugh because I hope you don't assume that because someone has a PE and title of "Engineer", you assume that what is on the plans is the right equipment for the application with what you're trying to accomplish. That said, I have no doubt a engineer is smarter than myself, but off the record, sometimes I wonder about their common sense.

Per trust, I've found it can only be developed over time. When it comes to choosing a specialty contractor and dealing with new people, just like a homeowner, get multiple bids, talk to the contractor, and don't be afraid to ask questions that may make you look like an idiot (you're not the expert, they are) and see how everyone responds. From my own experience, the better people to deal with who stand behind their word / work are not always the cheapest.

That is sort of the crux of my concern. We have a large old brick house in zone 5a that has remained a summer only house for 100 years (w/ one winter exception where it was rented to a who got by with space heaters and the old space heater in the kitchen. In the end he absconded and left a massive bill.

We want to convert the house to a year-round residence for us. The house is a 2 story brick structure with a large chimney in the center. Rubble stone cellar and a wood frame 1 story addition. House is about 1,600 sq ft for the 2 floors w/ no insulation so we’ll need to sort out insulating the attic and add storm windows which is about the extent of what we can do (yay old brick walls). The is an 800 sq ft wood addition added in the 20’s that we’ll sort out later (likely add a wood burning stove to make it usable during cold weather until we can insulate it properly).

Because the place is old, duct work is a non-starter, except possibly for the high velocity forced or type tubes the Unico systems use. So we are leaning towards hot water radiators of some type (baseboard, wall amounted or free standing cast iron). As NG is available (line was recently upgraded and new service installed) a NG hot water furnace is our current thinking. But the memory of the that enormous gas bill in the 70s haunts us.

We have plenty of space and digging is easy in our sandy loam (no rocks) so geothermal has been considered. We would likely need to go w/ a vertical deep system Instagram of a horizontal ground loop. My concern is the changing nature of sand to conduct heat, very good when wet, marginal when dry, would lead to too much variability in output.

So remembering the gigantic gas bill of yore, We are considering a hybrid system combining a gas boiler with a wood boiler, possibly a combination system, wood is no issue as we have plenty of acreage and even if we had to source it elsewhere truckloads of green wood is affordable in the area if you are buying at the right time of year, so with a little planning wood availability would not be a concern even if we never cut any of our own.

So given all this perhaps our concern with who we hire for the work. Our place is a bit of an unusual job. so thinking it would be good to research as much as possible and design something and get a pro in to look it over and make changes and corrections needed. We live in a house with hot water heat and big radiators and find it extremely comfortable.

Thinking of doing some diy on the job. If we go with an OWB or indoor wood furnace (in an outbuilding 60 foot from the house) burying the insulated lines is well within my ability. Thinking I could install the rads as well, but type, sizing and placement are the real challenges, especially in an old house. Our plan is to do the first floor of the brick house, closing off the upstairs with a hatch during the winter, heating only the 800 sq ft first floor. Plumbing the first floor will be relatively easy, but chasing heating pipes up to the second presents challenges, but we have figured out the best routing of the heating pipes. Radiators and installation will be a large part of the cost and needs to be done right, so spending time studying the history of hot water and steam radiators and finding a lot of interesting stuff about their design after the 1918 pandemic.

For the heating originally was thinking pex in the house, but have seen some really nice diy systems where black pipe was fitted to the purpose and I thought that looked good and practical.

If we go with some sort of dual system heating with wood and NG I would think a heavily insulated hot water tank in the system, allowing a hot burn (gun and run?) on the wood boiler to build up a reserve of hot water that can sustainably heat the house between burns with the NG in reserve in case no one feeds the boiler. Reliability is of the first priority so if something happens to me my DS would not be up Schitts Creek. Some sort of electrical backup is also a priority so any system we use (following the Power Wall thread and any Generator threads with great interest).

So the brains for such a setup would be important (Lambda controller?).

So I guess I could just hand the whole mess to a pro and pray (very hard) for a good outcome for our money. Up in the country there are about 30 inches of snow and the outside temps are currently 22° f outside and my trusty WiFi thermometer is saying the kitchen is 29°.

Very different setup from the OP, appreciate any advice.
 
/ New Home HVAC System #119  
So remembering the gigantic gas bill of yore, We are considering a hybrid system combining a gas boiler with a wood boiler, possibly a combination system, wood is no issue as we have plenty of acreage and even if we had to source it elsewhere truckloads of green wood is affordable in the area if you are buying at the right time of year, so with a little planning wood availability would not be a concern even if we never cut any of our own.
.

We love our fireplace and it will heat almost the entire home if we use it consistently but I would never want to rely on wood as my main heating source. I'm still young at 43 and enjoy cutting wood and burning it when I want to. I don't thing I would ever want to be in a situation where I have to. Just my opinion after 6 years of owning our home and burning wood.
 
/ New Home HVAC System #120  
JamesHW

Sounds like a interesting house.

Given the build and age of the house, first and foremost I'd look to see exactly how you're going to insulate and what kind kind of heat loss you have now vs when the proposed insulating project is complete.

After you determine the load of the house is satisfactory after insulation project is complete, then move to looking at what kind of system/systems you want.

My feeling is a detailed load of the house after insulation project is complete and satisfactory in your opinion, you can rest assured that the money you spend for conditioning the space is well spent.
 

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