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wh500special

HVAC contractor questions.

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wh500special

We’ve been sort of looking for a new house for a while.  Just want to get out of a neighborhood and back out where there is a little more freedom.   I like my neighbors, but I think at this point we’ve seen enough of each other.  
 

Today we stumbled on a house that is going to be going up for sale in the next month that is pretty close to what we’re looking for.  It has its quirks but generally, it’s nice. 
 

Unfortunately I’m not enamored with the heating system.  
 

this is one of those all-electric houses built in the mid 1980’s so it has a heat pump and no gas furnace.  It probably has electric furnace serving as the air handler but I haven’t been in it yet to see.  
 

Judging by the size of the house and our climate (lower Midwest) I’m guessing it’s probably around 2-tons which is what my current house AC is.  I think my current house - again, same size as this new one - has an 85k btu/hr 90-something% furnace.  Might be 100k but I remember being surprised how small it was when I looked and it’s been more than adequate on even our coldest stretches.  
 

So this other house will most likely be in same ballpark. 

We have a winter, but it only hits zero degrees once every 5-10 years.  Most of

the time we bounce around 20-40 degrees all winter with warmer and colder spells.  
 

Honestly, we have the crappiest winter here compared to anywhere else I’ve lived...it oscillates around freezing for 4 months meaning everything is cold, damp, and nasty.  And we get ice storms all season long.  100 miles north in Springfield, a real winter.  100 miles south, much more Mild.   We are

stuck in this zone where it’s not cold or warm and the ice on the lakes stays 1” thick all winter so we can’t ice fish or get a boat out there.  

summer, oppressively hot and humid.  But we get used to it by keeping the house 80+ degrees. 

 

anyway...

 

I’ve had a house with a heat pump AND a furnace before and know that once the temperature outside drops, the furnace would fire up to keep things warm without the constant running and “cool heat” coming from the heat pump.  But that heat pump was way cheaper to run than the propane furnace at the time when the outside temperature allowed. 
 

As part of an upgrade, I’d want to add a propane gas furnace and keep the heat pump too.  Electricity is cheap here for heat pump purposes but not so if you’re heating the whole house with it all the time with resistive heat.  Propane isn’t always cheap, but it is hot which is good. 
 

propane is the only reasonable choice as I don’t think a gas line runs out to this part of the county. I’d have a tank planted in the yard.  The basement is a walkout and unfinished so it couldn’t be any more convenient to install. 

In addition to being a hotter heat source,  I could handle a power outage on a small generator like I do now.  The house is in the woods, so I could see the first ice storm taking out a power line and my wife sitting there in the cold while I futz with trying to improvise a solution. 
 

since the house’s current heat pump is mated with an air handler/electric furnace and ducting we aren’t reinventing the wheel here and would most likely be a straight forward install for a contractor with easy modifications to what is there. 
 

so, the first of many questions...

 

what does a “typical” gas furnace installation cost these days in the 85k-100k size range?  I get it that there are 100 variables that can affect cost, but you guys that do this stuff see enough instances to know the range. 
 

I called a local contractor for a guess and all I can get is the responsible “we’d need to see it” response.  I get that, but are we talking $39, $5000, $10000, a million dollars?

 

I can see furnaces aren’t horribly expensive.  I can bring the gas to it and the exhaust since I’d go with a high efficiency/condensing unit.  I guess I could install it, but I’m not qualified to crack the Freon lines so don’t see that happening (although we do have all the equipment at work) .  I would assume for now that the heat pump/ac Is good enough to keep. 
 

any thoughts on cost for a minimal furnace  install?  I look at this is little more

complication than just swapping out a failed unit with a more modern version. 

 

again, I understand that there is a wide range of potential work involved.   But again, the scope of this isn’t rocket science.    Just looking for budgeting numbers so I can adjust my expectations if we end up buying it.  

 

Thanks,

Steve 

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oliver2-44

You might want to gather some info on the age and specs of the existing heat pump. Average Newer heat pumps can work down to 10F. High end Inverter heat pumps can work into the -0 something range. 

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wh500special

Really!
 

I guess advancements in refrigerants and operating conditions have changed things.  Interesting to know and I’ll have to look at it when we see the place up close.  
 

doesn’t solve the power outage thing, but might mean it isn’t a huge watt waster. 
 

Thanks,

steve

Edited by wh500special

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8ntruck

I just got a quote for a new heat pump/gas furnace.  100,000 btu size furnace, 5 ton a/c.  Air to air heat exchanger.  The furnace kicks in when there is not enough heat outside to pump inside.

 

95% contractor grade furnace system was $9K.  98% furnace system was $18k.  These are installed prices.  Just a furnace would probably be less expensive.

 

We also have a Gererac generator that runs on propane.  Starts up about 30 seconds after main power drops.  Just need to change the oil and keep a good battery in it.  It will run for about a week on 250 gallons of propane.

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Mikey the Monkey

Steve, we had brand new propane furnace and a/c installed last August. Idk technical specs of them but the house is about 3500 sq ft. We're very comfortable this winter in a colder climate than you. The whole job was under $9000. $4500 for furnace, $4500 for AC. I believe it is Amana. 

Edited by Mikey the Monkey

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squonk

@WHX24 Where Are You? :)  As Ollie said. Try to get the specs and age of the old unit. It may be near the end of life anyway.  Get it all installed as a package as supposed to trying to graft something on to an old system

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haydendavid380

One thing to remember is if your AC unit has any age to it it'll still have the old coolant in it, and won't be compatible with with a new furnace, so you'll have to replace that as well.

 

We are having our furnace and AC unit replaced next month and based on quotes are expecting to have to pay in the $6k-$8k range. That's with no additional ducts or anything, just swapping out the units. This is for a 1555 ft² house. 

 

As far as heat pumps, I've had several relatives that have had them in Southern Tennessee, and none of them have been very happy with them. They replaced with traditional forced air units, but I don't know how old the pumps they replaced were. Maybe newer models are better. 

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WHX??

I've been paged?!?!? 

Actually what you described Steve is common for your area but I still think anyone north of  the Mason-Dixon line should stay away from heat pumps like the Covids. 

Never liked them never will. Have had to replace too many reversing valves which are a real pain. Just too much expensive things to go wrong with them. The older ones forget it since R-22 is NLA. Yes newer stuff (HP's) is a bit better but also considered disposable out of warranty. Loaded with expensive electronics, mother boards etc. 

9 minutes ago, haydendavid380 said:

won't be compatible with with a new furnace

True both also untrue. If the old a/c is working good and not a POS that was ill taken care of. Easier to replace as a package and usually get a nicer job. 

 

21 minutes ago, haydendavid380 said:

expecting to have to pay in the $6k-$8k range.

Right about in my ballparks for "average" replacements. 

3 hours ago, Mikey the Monkey said:

$4500 for furnace, $4500 for AC. I believe it is Amana

 

About right Mikey...Amana tho???....eeewwww :)

 

Things to keep in mine get more than a few quotes from reputable contractors. Be wary of high prices and low ones. One should find several in the same price ranges so those are the ones to focus on. Compare apples to apples and watch out for the professional salespeople who want to upsell you to a Cadillac ... comfort advisors are what they are called nowadays and trust me they have setting the hook down to a fine art. 

 

I get this question asked alot ... what is the best brand? I come right out and tell them it's all junk ...just somes better junk than others! Most times the difference is how it is installed. I can take a top of the line unit and throw it up in the air and where it lands it gets installed... :angry-nono: or pay attention to detail. Supporting ductwork is everything. 

Bounce model numbers off me I'll tell you what junk you are buying.

 

Back to Specials post.... electric house are taboo up here nowadays. we do not have very good electrical rates and most houses in the 70's 80's 90's poorly sealed.

 Yes a gas 96% two stage furnace and ditch the heat pump if it R-22.  If you are serious about buying the place get a reputable HVAC contractor to look at it before hand and tell you what you are buying  

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Jeff-C175

If a contractor is unable or unwilling to perform a PROPER HEAT LOSS AND GAIN calculation in order to properly size your heating and cooling equipment, ask them to leave.

 

I would venture to say that over 90% of heating equipment these days is drastically OVER SIZED for the application.

 

I recently installed a 64K BTU hot water boiler to heat my 1800 sq ft home in NJ after running detailed heat loss analysis (MYSELF), and even IT was larger than necessary but the smallest in the product line.

 

It replaced some big old monster of 155K BTU and the new boiler has been handling the heating load JUST FINE for six winters so far.

 

Every contractor that quoted the job was going to replace with same size and was unwilling to install what I wanted.  Some didn't even know what a heat loss analysis was!

 

I ended up doing the job myself.

 

Do NOT replace "same for same" BTU wise without doing a proper heat loss analysis FIRST!

 

https://www.pvhvac.com/blog/is-your-hvac-system-too-big

 

https://www.google.com/search?q=why+are+heating+systems+so+often+over+sized

 

Edited by Jeff-C175
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squonk

Good point Jeff! 

We have a lot of post WWII project homes around here. They were originally heated with these little furnaces that looked like glorified wood stoves with a gas burner. Some had fans adapted onto them.The heat came out of louvers and they were rated 60,000 BTU's at 65% Efficiency. A friend of mine lives in one of these places and a few years back he had to replace his furnace. The local contractor replaced it with a 65,000 BTU at 95% Efficiency. His logic was what BTU came out went back in. Never mind the old furnace was heating the house with around 40,000BTU's.The rest was going up the pipe!  That stinkin new Furnace fires up and only runs a couple of minutes. Bout blows them out of the house when it's on. I told him to expect to be replacing the heat exchanger sooner than later.

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Jeff-C175

The over sizing of heating equipment dates back to the Spanish Flu Epidemic of 1917-1918 (or so the story goes).

 

People at that time believed that FRESH AIR in the home was crucial to keeping the Flu at bay.  So they opened all the windows, all the time.

 

They needed bigger boilers and furnaces.

 

25-50 years later, after everyone had forgotten why they were oversizing the heating equipment, they just went ahead and replaced the equipment with the same size, figuring that was what was needed.

 

And the trend continues...

 

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wh500special

Thanks guys.  Good information.  And some good bookends for pricing.  That's exactly what I was looking for.

 

I try to be preemptive and not wait until an appliance dies before replacing it, and would do that here as well.  No sense being caught over a barrel.  So unless disaster befell the system, I'd have a lot of time to get plenty of quotes and visits to find a decent value.  The issue I've seen and heard though is that the range of costs is so wide it's hard to have any feel for where you should be.  All I really wanted was a rough order of magnitude idea and you guys delivered.

 

My experience with HVAC contractors is limited.  On my last house we expanded the living space into a finished room in the attic around 2005.   It was too much for the AC that was there but the propane furnace was fine and only a few years old.  So I had multiple contractors out for inspections and analysis.  I don't remember the numbers, but the cheapest guy thought replacing the blower with a stronger one would do the job and the most expensive guy was tearing out the whole system and even replacing ducting.  The costs ranged from a few hundred dollars to over $10k.  It was frustrating as most of them seemed to be shooting from the hip and just selling what they wanted to. 

 

Gave me a bad impression of the field.  And the local guys here who weren't initially cooperative on the phone or when I've needed replacement parts for my current unit have reinforced that notion.

 

The guy that made the best impression on the previous house was the one who got the job.  He wasn't the cheapest or most expensive but offered a solution that made sense to me.  He's the one that upsold me on the heatpump which turned out to be an excellent return on investment.  At the time there were tax credits and rebates that made the increased cost of the HP a wash AND soon thereafter propane shot to $4+ a gallon.  So being able to use the grid to heat the house in cool weather at my electric rates offset the high cost of propane in the cold months when the furnace had to run.  The HP ended up being a real savings.  

 

I wish that guy wasn't 200 miles away....

 

The cooling capacity of the HP was fine for the increased load which was the original point of the project so I gauged it a succes.  He was the only guy that I witnessed measure the outside of the house and run his calculator to figure out a good size or verify the furnace or whatever he as doing.

 

I'm no stranger to heat transfer calculations. It's simple and straight forward math so it's a shame to hear that some contractors don't make the effort.  But I'm not surprised since laziness seems to be an epidemic.

 

I appreciate the comment  that new furnaces are all just different grades of junk.  There was a time when they were simpler and more reliable but I guess in modern times they are sophisticate and somewhat delicate.  I guess the buying public prioritizes things they can see and those geewhiz products that have internet capability over reliability.  Maybe in real terms though they are cheaper now(?).

 

Thanks all!

 

Steve

 

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wh500special

Next question:  DIY installation.

 

I remember when I still lived at home (long time ago!) that dad bought a new AC and furnace unit from Sears (I think) and put it in himself.  Do they still sell the units with the captive refrigerant lines that don't break their seals until attached, or is this a thing of the past?

 

As part of the deal a tech came out for an inspection prior to commissioning the unit to verify compliance with warranty and whatnot.  Dad recalls he had to add a little bit of refrigerant to make up the difference and bring it to spec.  That unit ran flawlessly for the last 10 years we lived in that house with never a service call.

 

I'm not at all discounting the value of experience with having a contractor install these things but wondering if this is still a thing.  I don't really have any intention of doing it myself, just curious.

 

Steve

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shallowwatersailor

Steve, we replaced one of our house's original heat pumps 1-1/2 years ago with a Lennox 2-1/2 ton unit. In the mid-to-late 2000's, evaporator coils of all manufacturers were having a problem with fabricating the bends. To lower production costs they cheapened the product. After a certain number of years they would fatigue and start to leak. We went a year re-charging it  until deciding to replace it.

 

Without digging out the paperwork, I remember that the new unit has a variable speed blower with a two stage compressor. It does have the supplemental resistance heater but they have rarely if at all come on. This is set for 64-66 degrees in the winter. The blower runs constantly circulating the air using the variable speed as needed when the compressor runs. When I had it installed, I had additional duct work run in the unfinished area which also meant going up an additional 1/2 ton.This is the second winter for it and I have been very pleased with it. 

 

Our house is 4400 sq. ft. 5 bedroom with a walk-out lower level, Finished space is 3300 sq. ft. and 1100 sq. ft. just insulated. The main floor still has the original 13 year old 5 ton heat pump that we keep at 65 degrees in the winter. I am just waiting for it to die to replace with a similar Lennox unit. But lucky for my pocket, it keeps chugging along! We did go through Costco for the unit which had very favorable terms. I do suggest checking that out, even if it means signing up for a year's membership. Luckily the HVAC contractor was the same Lennox dealer that serviced my Lennox fireplaces. Long story but he actually comes over the mountain for me as the nearby Lennox dealer wouldn't service my Lennox fireplaces.

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shallowwatersailor
10 minutes ago, wh500special said:

Next question:  DIY installation.

 

 

 

For my first house in 1979 (when I was younger!), I installed my own central A/C unit. It was a newly constructed house in a subdivision so obviously built for a price. The developer wanted $1600.00 for the A/C unit that would be plunked on the ground right where I would build my deck. Not good for having a Summertime conversation! I was able to buy on sale through a HVAC supply house a complete 3-ton unit for $700.00. A buddy and I installed it one Saturday. The hardest part was modifying the existing furnace to accept the evaporator coil,  I also ran the copper lines to the opposite side of the house without bedrooms to make a quieter operation with the added bonus of being in the shade. This unit did use the now banned R-22 but you didn't need to be licensed to work with refrigerants back then. I borrowed a vacuum pump from work. Luckily my soldering skills were up to par.

 

I would pay someone to do it all now.

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Handy Don
11 hours ago, wh500special said:

Next question:  DIY installation.

 

My soldering skill is good. My speed is pitiful compared to a good plumber.

 

For me, I was replacing a fairly involved system for 3,300 sq ft. (hydronic+domestic, two-zone forced air with an existing solar HW system for domestic preheat and an existing AC compressor). Did the full heat loss/gain analyses myself (double walls, 9 ½" insulation in walls, 24" in ceiling, insulated basement walls, coated glass windows). The heat load came out to less than 80,000--two contractors "rule 'a thumbed" it at 120-150k and wouldn't look at my data. $12-16,000 estimates. Bye.

Did a full plumbing design myself, spec'd all the components, and found an installer willing to buy the parts through his distributor for a flat fee and then dismantle/pull the old system and put the new pieces together at his regular labor rate with me interpreting the design and holding things. $4,000 complete including a Benjamin each as tips for the plumber and his helper (his pipe cutting and soldering was neat and really, really fast--done in 7 hours)! Since then he's been back to help with a couple of tweaks to my initial design--check valves to stop thermo-siphoning (shoulda seen that coming) and an expansion tank so I can safely turn off the water to the house when I'm away. (Street supply will get check valves this summer.) I used a gas commercial 100,000, 96% efficient water heater (what you might see in a restaurant) since it supplies domestic HW as well as the hydronic. I installed the PVC air inlet and exhaust.

The lesson here was that I was willing to do the legwork, the analysis, some of the installation, and the design and had the experience to interpret that to guide and work with the tradesmen successfully. It took hours and hours. And I had to be willing to own the result--the plumber guaranteed his work, but not the capability or effectiveness of the entire system. And I knew I'd be in this house for long enough to make it worthwhile. YMMV

Edited by Handy Don
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squonk

As far as DIY. The refrigerants of today run much higher pressures than R22. Lines need to be brazed not soldered.

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WHX??
1 hour ago, squonk said:

Lines need to be brazed not soldered.

We still solder Mike but use a $$ solder with a very high silver content.  Offsets the cost & labor of N2 purging.  Zero problems unless one of the installers is recovering from the bottle flu. Trend now a days is no heat... press fittings & the like. Way more problems with leaking factory coils.... some body in a factory some where recovering or to get home to dinner I suspect. Not to mention poor designs. 

 

On 3/19/2021 at 8:43 AM, Jeff-C175 said:

PROPER HEAT LOSS AND GAIN calculation

Almost useless on existing houses since R and U values can only be guessed at unless you spend hours at it. Time is money. Two different guys will come up with two different values. Thermal image tells the picture.  New house a whole different story. Most contractors (guilty as charged) will oversize the unit because they don't want to have problems. Callbacks we call them and ouch in the pocket book if we have to go back and put in a different unit to keep a customer happy. 

 

DIY installs are pretty much a thing of the past. The most mechanical minded  of us can read the install manual cover to cover but that doesn't make up for experience or the proper tools. Especially with mod con boilers and the high tech of stuff. Modulating furnaces, variable speed blowers and control boards that will do yer dishes when it's done heating the house.

You can watch all the you tube vids all you want but factory tech support is sometimes a must and if your not a contractor they will tell you to get one and hang up on you.  It's a full time job just keeping up with advancements in things, then throw in the planned obsolescent factor!  

 

Stay away from new gimmicks ... your being used as a guinea pig, Never listen to the manufacture's propaganda... they love to blow their own horn! :)

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Jeff-C175
2 minutes ago, WHX24 said:

unless you spend hours at it

 

I spent YEARS at it on my home!  :eusa-think:

 

I studied, studied, studied.  Meticulously tracked the degree days for a couple years vs. fuel usage.  I knew exactly how many BTUs per Degree Day I needed to have.

 

Measured supply and return temperatures.  Knew exactly how much baseboard radiation was installed.  Ran Manual J several times with different scenarios of insulation, etc...

 

BUT... since I pretty much rebuilt the home top to bottom, I  KNEW  what the construction was.

 

And since I was in no rush to replace due to a 'broken' system, I could afford the luxury of taking as much time as I needed.

 

I understand your point that time is money and not wanting call backs.  I still think a Manual J should be done.  Once you've done a few it doesn't really take that long.  And use the 'worst case' conditions if you are that concerned about call backs.

 

The old boiler was THREE TIMES the size it needed to be.  That's unconscionable,  and ALL the contractors I spoke with (a half dozen) were either unwilling or unable to run the numbers.  They ALL wanted to install the same size boiler that I had. 

 

My new system correctly sized has cut my oil usage in HALF (maybe even a little better than that) !  and there has not been any whining from the better half ... "It's cold in here!"    

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squonk

We had 2 systems at work 410A soldered in by previous employee. Had to re do both. oil everywhere! :(

 

Got an Emergency call from a school. New Kitchen with walk ins going in and the reefer guy didn't show up for 4 days. Food coming. We go there.  Refrigerant lines are pressed in and small holding charges on them. We have to finish the electric, Install the X valve bulbs and final charge. I do the cooler and my partner does the freezer. I get mine done and am picking up while the other guy finishes the freezer. Condensers in the basement. I'm upstairs and hear BOOM! Oil is everywhere again! Dude who ran the lines missed a crimp in the ceiling of the basement on the freezer.:rolleyes:

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