Monster furnace DIY or find a Pro?

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  #1  
Old 12-06-11, 08:40 AM
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Monster furnace DIY or find a Pro?

Hi all,

New home owner look for information. I purchased a house built in 1953. The furnace is also from that era. The home inspector did put in the report the furnace should be replaced but our lawyer said if it ain't broke don't fix it but he did ask the seller to have the unit serviced which they did by having the ducts cleaned.

1. I live in West Orange, NJ
2. House is Center Hall Colonial with around 2400sq/ft. Construction is wood panel siding, wood board exterior, 2x4 wood beams, insulation and plaster wire mesh.
3. The furnace is an American Standard/Radiator Standard from the 1950's the only marking on it I can find is Sunbeam. Its around 5' W x 3.5' D and 5' H.
4. Gas/forced hot air
5. n/a
6. single zone
7. Filtrete 3M-50

Things I've done so far, I changed the thermostat to a new programable one replacing the junky round mechanical thermostat. The system has two wire bundles, R and W for heat and Y, G, Rc for cooling. And I've also taped all the gaps where there were holes in the duct work for the add-on A/C/

I have two simple goals the easy one is:
I am trying to find an owners manual for this thing. I want to figure out where I change the air filter, or does the air handler not have a filter slot? It also looks like the a/c is an add on with its own air handler.

The hard goal is to eventual replace both with a single cabinet one quarter the size of this one.

Top view


Side view - and yes in the top right corner of the pit is a 5' ladder


Overall view
 
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  #2  
Old 12-06-11, 07:43 PM
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I wouldn't touch that thing with a 10 foot pole other than to rip it out by the roots but, to answrer your question about the air filter:
It is probably supposed to go in the compartment below the vent pipe. I'm presuming that's where the blower is.

If this system was installed in the 50s, the ducts were probably not sized for A/C. If you want it done right, BE PREPARED for major expense.
 
  #3  
Old 12-06-11, 08:17 PM
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Duct cleaning has nothing to do with servicing the unit! They are total different things. He should have had the HVAC system cleaned just not the duct
 
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Old 12-06-11, 09:24 PM
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Wow... See the saddle valve on the gas line?

Why is it built installed in a hole? I wonder if thats a mini bomb shelter for it for if it ever explodes.....

I am really wondering what the string is for going through the small hole in the duct work. I would not pull it, might be the detonator!!!!

But anyway it might have brakes. That metal oval thing hanging off the side looks like a brake fluid resovoir from a 68' olds cutlass I once owned. Hmm ...

All jokes aside though and I am sorry I could not resist but, I am with grady. The old saying, "once you touch it you own it."

I really would not do too much with it and at all costs get a CO detector asap if you dont have one already. You dont want to wake up dead.

Mike NJ
 
  #5  
Old 12-06-11, 11:42 PM
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No, that's not a saddle on the gas piping. It's a tap off the shutoff valve for gas for the pilot burner, including a valve to shut off the pilot burner gas supply.

Common enough on old equipment.

I agree that cleaning the ducts is not servicing the furnace, and having it carefully checked on old equipment like that is VERY worthwhile.

The thing hanging off the side was probably once a reservoir for a humidifier that was decommissioned at some time.

I would suppose that the air filter is or ought to be behind a door in the the same end of the furnace as the vent pipe, with the air flow going into the furnace on the side where the vent pipe is and the warm air plenum on the right side where the air would flow through where the humidifier was and then up and out on the right side of the furnace. You can see where the fan limit switch is located ---- the return air ductwork would be to the left of that, on the left side of the furnace.

My reservation about servicing the furnace would be getting access to do proper inspection and maintenance, not the age of the furnace. It would probably be no fun. When it's no fun, it may not get done, which makes a good inspection all the more important, since maintenance and inspection may have been neglected for years.
 
  #6  
Old 12-07-11, 12:07 AM
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Replace that pos before it poisons you with co or burns the house down.

It should have been changed 30+ years ago.
 
  #7  
Old 12-07-11, 02:31 AM
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Have it inspected. If the heat exchangers are OK you just need to do whatever maintenance may be needed and it will be fine.

There is no need to replace a furnace just because it's "old." Replace a furnace if it's unsafe for some actual reason.

It might also be worthwhile to replace the furnace due to it's releatively low efficiency. It's 70-75% efficient compared with 90% plud efficient furnaces available today. But that would be your call.
 
  #8  
Old 12-07-11, 05:30 PM
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You can't tell if a heat exchanger is bad just by looking at it without complete dis-assembly.

Once startup and shutdown losses are taken into consideration, the efficiency could be as low as 55%.

A 50 year old pos could lack the safeties even found on a 20 year old unit - vent safety switch and rollout switch.

Keep anything more than 30 years old running is absolutely absurd. Had it been replaced 20 years ago, the savings could have payed for a new furnace several times by now.
 
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Old 12-07-11, 06:23 PM
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Well Muggle --- I guess every furnace should be replaced whenever it's seen by a repairman. That's certainly the philosophy used by a regrettable number of heating contractor who send "repairman" out to sell new equipment to people who may not need it.


Pretty much every furnace is engineered to extract as much heat as possible and still insure that the combustion gasses will rise through the vent and wont condense into water. 70-75% efficiency is a reasonable ballpark level to suppose in my view.

Again, it's quite common for those who aim to sell people new equipment to exaggerate efficiency levels to minimum they can possibly justify.

You are certainly entitled to state your opinions. Personally, I think they are too negative.

If the owner wants to replace the equipment, I wouldn't argue with that. If he wants to continue to use it, I'd have no objection to that if it's inspected and found to be safe and has any needed maintenance work done.
 
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Old 12-07-11, 11:20 PM
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70-75% efficiency is a reasonable ballpark level to suppose in my view.
Clarification for the thread starter:

Natural draft furnaces vent air continuously up the chimney, reducing seasonal efficiency by 5-10%.

Take another 3-5% off for the pilot.

Take another 5-10% off for having a very thick heat exchanger which takes 2-5 minutes warm up (while an enormous amount of heat pours up the chimney) before the fan even comes on. (at the end of the cycle some of the residual heat stays in the house, most of it escapes up the stack)

So, even though the steady state efficiency could be at high as 80%, the seasonal efficiency is always well below that.

With modern equipment, the fan is on within 30 seconds, there's no standing pilot, and the exhaust is vented by a fan which shuts down when the call for heat ends.

Why is it built installed in a hole? I wonder if thats a mini bomb shelter for it for if it ever explodes.....
That feature might come in handy.
 
  #11  
Old 12-09-11, 12:51 PM
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Our first fuel bill was $201, 55 for electricity and 145 for gas. October was a bit warmer than normal so I think Jan/Feb/Mar when its bitter cold we'll see some real big bills. The previous owner had an average bill of $240/mo our energy company told me when I signed up. The change from mechanical to the 3M-50 should help lower energy costs. Program has been set and wifi-enabled so I can tune it.

Thanks for the tip on the filter, I'll look under the vent pipe to see if I can find a door or slot for it. I believe the duct cleaning was in addition to servicing the unit. I saw the bill the owner paid was $680 so I think its a bit high for just ducts?

I showed the photos I took to an HVAC guy he said he hasn't seen one of these in ages and told me these were built to last, all solid steel and heavy. The unit does a pretty good job at heating the house. It is a monster, when it runs the gas meter needle spins fast, the roar of gas being burned and the radiant heat being emitted in the boiler room is tremendous. We have a new CO meter and test it monthly. I also installed a fire extinguisher near by.

The next simple change I will do is seal the seams around the duct work and tape it then wrap it in insulation in the unconditioned crawl space .

As for a new radiator it will have to wait a bit, we are paying two mortgage's (old house is being put on the market) and the money we could be saving for a new furnace is paying both bills. We also don't want to sell our stocks or dip into savings.
 
  #12  
Old 02-22-12, 10:24 AM
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Thanks for the responses

I finally got down and dirty with it. I found where the filters are. There is a bank of 4 filters feeding two huge blowers powered by 1 motor. The heat exchanges look massive and solid. I retired two broken humidifiers and sealed their openings. One was plumbed but not actually doing anything but consuming electricity and the other was not connected to a water line sitting on the return side. Our January utility bill was $435 keeping it 71 during the day and 67 at nights and 66 whenever we were away in 07660. The house is leaky and a better fix would be to install new better insulated windows and pockets.
 
  #13  
Old 02-22-12, 10:50 AM
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Our January utility bill was $435
Good Lord!!!! Thats half my gas bill for the whole year!!!!

Mike NJ
 
  #14  
Old 02-23-12, 10:26 AM
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What is that green/teal thing on top/middle of this?
 
  #15  
Old 02-23-12, 02:53 PM
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My guess is it is the evaporator coil. Note what appears to be Insultube toward the bottom/left of the picture labeled "overall view".
 
  #16  
Old 02-23-12, 03:00 PM
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Kinda figured it was.. But what way is the air flow going??
 
  #17  
Old 02-23-12, 06:49 PM
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Based on the gas line going in on one end & the vent coming off the other, I'd say the air flows into the evap coil on the gas pipe end then out the top. It would appear the plenum on the vent end would be the return? Certainly a strange looking set up. Maybe pitogo will come back & explain.
 
  #18  
Old 03-05-12, 04:06 PM
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The house is leaky and a better fix would be to install new better insulated windows and pockets.

Read more: http://www.doityourself.com/forum/ga...#ixzz1oI4ExjEa
That a good approach; you'll need a much smaller furnace once the house is retrofitted.

Air sealing and adding insulation (to the attic, at least) have a good return on investment.

Windows don't have a good roi - don't count on significant savings unless they're single pane (if they are, shrink wrap is a good temporary solution) or leak badly. It's a good idea to get the frames sealed though.
 
  #19  
Old 08-06-12, 01:37 PM
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I found out more about the history of these units. The hot air conditioning is a Sunbeam by American Standard. (they used to call the furnace an air conditioner back in the 1950's) It is a model is K-150 rated at 150,000 BTU input from natural gas and 120,000 BTU output. It was originally installed in 1953/4 with the house. The original blueprints reflect the pit is in on the original plans of the boiler room. It runs very well and keeps us warm in the winter. Our house is very leaky and need all that power. The return is on the left while the output is on the right. The cold AC system was installed sometime in the 80's. It is a retro fit and you can see the ductwork was added on. The evaporator is a York straight coil with an outside 5 ton York condenser. The condenser was replaced 5 years ago so its not really match to the coil. For normal heat operation, the AC portion on the top is closed off with duct dampers on the intake and return from the AC coils. The air would come in from the top of the furnace travel down through four 20x16 filters pulled by two blower fans. The air would then travel back up through the gas fired heat exchangers and out the top right side. For normal cool operation, a damper is installed in the furnace output duct and the dampers to and from the AC coils are opened. Cooling bills are just as bad and the evaporator blower fan is much louder than the furnace fan.

I think this is a system not for a DIYer but for a pro. I am looking at complete heat/cool system that is 18Seer/98.2% AFUE from Lennox and a Rheem hot water heater which can take advantage of an energy rebate. My only concern is that the Lennox system while very efficient will not last the 59 years+. Reading history, heating systems were a luxury and were very expensive back when this unit was put in. Because they were a luxury they were built to high quality standards and built to be very durable. (I can attest to that) But sometime in the 70's central systems went from being a luxury to a commodity and every corner was cut to get the cheapest units out. Thinner sheet metal, thinner paint, everything only built to minimum standards which meant it will barely last past its warranty. We are getting junk no matter which manufacturer it is.
 
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Old 08-07-12, 12:35 AM
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[quote]My only concern is that the Lennox system while very efficient will not last the 59 years+

Read more: http://www.doityourself.com/forum/ga...#ixzz22qIactkp
[/quote

A decent furnace properly installed may last 15-25 years.

I am looking at complete heat/cool system that is 18Seer/98.2% AFUE
One thing to remember is that the law of diminishing returns applies to efficiency.

High end brand name equipment can have very expensive parts to replace down the road.

A middle of the road 90-95% efficient 2 stage furnace with a efficient variable speed blower (not multi-speed) may cost $1000+ less than a top of the line 98% modulating unit.

On the cooling side of things, SEER is measured at a relatively low ambient temperature (in the 80s with an adjustment factor), while EER reflects performance in hot weather - 95F outdoor, 80F indoor.

The high seer units aren't that much more efficient than the base 13 seer models in hot weather. For example, 13 seer units tend to be 11 EER; 14-15 seer = 11.5-12 EER; 16-18 SEER = 13 EER.

-------------------
The other thing is that a high efficiency furnace is not the cure all for high utility bills - don't expect your gas consumption to drop by more than 1/3rd.

It's far more important to reduce heat loss to begin with than invest in a new heating system right away.

A load calculation should be done prior replacing the furnace - 120k BTUs is an enormous amount of heat - enough for a newer 3000-4000+ sq ft house. (...the same goes for cooling capacity)
 
  #21  
Old 08-09-12, 06:16 AM
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just a general comment..you are wise to replace when you move in a new place. i waited over a decade and lost a ton of money. i would have been way past payback period and raking it in had i done this right away.

so definitely get something new you cant not save
 
  #22  
Old 08-22-12, 12:56 PM
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muggle, thanks for the input. I signed up for a Lennox system. 21Seer 5 Ton AC unit with what they sized us for, a 90K BTU 98.2AFUE. I am concerned I am going from a 150K 80% efficiency to a 90K 98.2% efficiency system. It very well may cost me the same in natural gas of the 90K system is trying to keep up with our heating demands. The attic has 4" of insulation and they are targeting an additional 2" of cellulose under the attic floor as well as attic sealing.

Its a signed contract but not yet a done deal should I be worried? The current unit other than its age 59years old works fine but not as efficient and a bit louder than modern systems. 90K was from manual J they put into a computer but I'm having it re-done with a blower door test and measurements from actual blue prints of the house.
 

Last edited by pitogo; 08-22-12 at 02:19 PM.
  #23  
Old 08-22-12, 02:46 PM
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The attic has 4" of insulation and they are targeting an additional 2" of cellulose under the attic floor as well as attic sealing.


These days, it's good to have around R40-R50 insulation in the attic.

Cellulose is R-4 per inch, so 12"+ is desirable.



--------------------------------
Modern furnaces need to move 50% more air than conventional models - odds are that the existing air ducts wouldn't be large enough for anything bigger than 90k.

5 tons of cooling though is a lot for a house that requires a 90k furnace unless it hits 100F+. If the air ducts aren't large enough for the 2000 cubic feet per minute a 5 ton unit needs, the coil might freeze up. (...at best, you may not get the 21 seer you're paying for)

With respect to energy use, smaller units burn less gas over a longer period of time, so they don't consume more energy. Over-sizing actually increases energy consumption because it takes a several minutes for a furnace actually reach rated efficiency.


Total energy used = power (BTUs/hr) x run time

...if the power is reduced by 50%, run time doubles but the product stays the same in theory. (in practice, run time doesn't quite double due to losses associated with cycling on and off)
 
  #24  
Old 08-22-12, 03:01 PM
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I am concerned I am going from a 150K 80% efficiency
The old furnaces could be up to 80% efficient when actually running, however...

- There's a continuously burning pilot
- There's a continuous flow of warm air up the chimney
- The heat exchanger is very thick, so it takes a long time to warm up and cool down; at the beginning of each cycle, heat pours up the chimney for a few minutes before the fan comes on. (...in modern units, the fan comes on within 30-60 seconds) At the end of each cycle, much of the residual heat in the furnace goes up the chimney as well.

...so the average efficiency could be anywhere from 60-70%. You should see a very significant reduction in gas consumption.
 
  #25  
Old 08-22-12, 03:04 PM
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I seriously doubt that old monster had an AFUE of 80%, more likely somewhere around 65% at best. Even then it was likely 50% larger than necessary. Does the new unit have a two-stage burner? If so, I predict that it will be on the first stage only at least 80% of the time.
 
  #26  
Old 08-22-12, 03:28 PM
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It is obvious the furnace is an energy hog and will not improve, but will become more dangerous to you and your family.- Get new unit and it will pay for itself and make you safer. Trying to use a 35+ year old gas furnace is a waste of time.

I bought a 25 year old townhouse and it had a old "65%" efficient furnace. Being a home inspector, I did my own inspection and spotted a very questionable heat exchanger (also known as death trap on a cold night in MN). Since I had a contract that allowed me to have the home inspected and the inspector noted the furnace and "red flagged" it in the report. I paid my friend $250 to find things I missed and got got a $3500 price reduction from the seller, then replaced it with an 85% efficient unit with variable speed fan since a 95% furnace would have been a problem to install and vent in a fully finished townhouse that really did not make much to heat with only two exposed walls with 3 sliders and 2 interior concrete block walls between me and the other neighbors. - Now, my AC cost more than heating in frigid MN, so that is my next target.

Sometimes it makes sense to get rid of the junk and save money.

Dick
 
  #27  
Old 08-22-12, 07:08 PM
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I believe the current unit is pushing a lot of air through the ducts. I measured air return trunk its 8" tall and 34" wide and the output is 8" tall and 45" wide. It runs through the center of the house in a 3' crawl space. Crawl space is on a poured concrete foundation. Along the main trunk the output are branches fed through dampeners and out to the house.

I saw concerns about 5 ton coils freezing over. I would love that, seriously, but sadly it doesn't happen. On very hot days (we had quite a few) I saw my thermostat go in reverse with barely cold air making it out through the ducts. I checked the filters�two 16x20 side by side (32"x20")�they were clean and the coils were not frozen. The evaporator is older and the condenser is 4 years old. I just felt sorry for the poor condenser which ran for hours on end and couldn't meet the thermostats meager request of 76�F. The cold air blower pushes more air though the ducts and is much louder than the heater.

The heater is a single motor powering two blower sections. The air return travels from the top going down across exhaust pipes from the heat exchanger through 4 filters of 14"x20" in a 2x2 matrix. The blower then pushes the air though thick heat exchangers and out the top of the unit to the output ducts.

Pilot lights are turned off when seasonal heating cycle is over. I also adjusted the fan limit switch to turn on sooner and turn off later. Temp swing allowed is 1.5�F set with the Filtrete 3M50.

I think I may be sweating the details too much and overly concern we will freeze to in the winter or worst case, will still rack up the same bill. Some say junk but I say quality. It is built in the USA with thick heavy construction and it has survived 59 years and is still performing well keeping us warm but at a moderately high cost relative to energy costs back in the 50's. Its like saying a classic car is junk because new chevy's get better mpg. I think everything today is junk. I read so where a story about goodman who came into the industry and under cut everyone which forced all of them to cut corners and cut costs to remain competitive.

One thing about over/undersizing even if we oversize to a 110K BTU instead of the recommended 90K BTU, the furnace also has a variable capacity burner which can go anywhere from 35% to 100%.
 
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Old 08-22-12, 07:36 PM
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pitogo -

It seems like you have made up your mind that as long as you and your family are alive (as in CO), can pay for the fuel and can make it work without doing anything more and then wish you had something better when you go to sell.

Dick
 
  #29  
Old 08-22-12, 07:43 PM
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A 8x34 return duct sounds insufficient for 5 tons.

One thing to remember is your current 5 ton system most likely isn't delivering 5 tons of cooling due to low airflow, having a new condenser mismatched to an old coil, possibly incorrect charge, etc.

Over-sizing is problematic because it reduces dehumidification (shutting off before the house is dehumidified), as well as capacity/efficiency if there isn't sufficient airflow.

Adding attic insulation will help immensely with the cooling load, and having a properly matched system with correct airflow should help with capacity.

Ultimately, if a manual j (new attic insulation included) indicates that only 3 or 4 tons of cooling are required, don't get a 5 ton unit.

A properly sized and installed 13 SEER model can actually perform much better than a top of the line 20+ SEER model.
 
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Old 08-22-12, 07:49 PM
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Edit:

There are a few versions of the 90k slp98 with different blower see http://www.lennoxcommercial.com/pdfs...naces_data.pdf





One thing about over/undersizing even if we oversize to a 110K BTU instead of the recommended 90K BTU, the furnace also has a variable capacity burner which can go anywhere from 35% to 100%.
Be sure that the dealer gives you the matching lennox modulating t-stat which can actually control that furnace properly.

With a single stage t-stat, the system won't modulate -> it may stay at 35% for a few minutes and ramp up whether the extra heat is needed or not.

Over-sizing defeats the purpose of getting a top of the line variable capacity unit, so purchasing a 110k btu furnace when 90k is required would be a mistake.

-----------
One thing to consider is that not all duct systems are suitable for modulating furnaces; if your ductwork has long runs or some rooms get poor airflow, a 2-stage unit might be a better choice.

overly concern we will freeze to in the winter or worst case, will still rack up the same bill.
You won't freeze.

85-90k is a large amount of heat - equivalent to around 17 1500 watt electric space heaters running on high.

Where I am (it can drop to -10F), a 90k furnace (replaces 110k conventional) can heat a newer 3400+ sq ft house with capacity to spare.

Bigger is not better.

The bill should be at least 30% lower if the equipment is sized, installed, and set up correctly. (with air sealing and adding insulation, you may save 40% or more)

If you post more info about the house, we could get a better idea of whether what you've been quoted is in line or not...

1. Size, number of stories and shape
2. Type of construction if you know (double brick vs framed)
3. Type of windows
4. Sun exposure
5. Climate info - location, etc.
 

Last edited by user 10; 08-22-12 at 08:47 PM.
  #31  
Old 08-23-12, 06:17 AM
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I agree, bigger is not better.. I went from an old 115k furnace down to 60k two stage. Most of the winter, it runs on 1st stage.. Very rare it goes into 2nd.. ONly time it does that when it's coming out of set back, and when the temp is down to -15˚.

Get more insulation in that attic.
 
  #32  
Old 08-23-12, 08:59 AM
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Thanks, I think you guys are knocking some sense into me. I was just afraid of giving up on my SUV if you may in an analogy. Its like I have this big inefficient SUV that our family feels safe in but a properly sized car will do just fine and more efficiently. I have a blower door test this weekend and will do the manual J again. Because of the overwhelming responses, will trust what they recommend.

The system is mostly Lennox
SLP98UH090XV60C AFUE=.982 90K BTU
5 Ton AC, 16 SEER, 12.5 EER
Condenser: XC21-060 Coils: L*42/60Y9 AHRI: 5194231
T-stat iComfort, Humidifier Aprilaire 600 and Air Purification PureAir

The upgrade also includes a Rheem Powervent 43VP50E2 50 Gal EF=.67
Attic insulation and air-sealing.
 
  #33  
Old 08-23-12, 12:51 PM
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My advice with respect to the water heater is to avoid a power-venter if you can.

They're noisy, have electronics to fail ($$$ down the road), and don't heat water without power.

The best type of tank is direct vent - just like natural draft (no electronics to go bad, pilot ignition) except the combustion air comes from outside and they can be vented through the wall.

Rheem Residential Gas Water Heaters - Fury Direct Vent (Horizontal Option) Series
 
  #34  
Old 08-23-12, 01:46 PM
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I agree with Muggle on the water heater! I hate power vent water heater. As he said, the noise is what I hate about them, and also, when the power goes out, you won't be able to make hot water.

I kinda question on the A/C size tho...???
 
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Old 08-23-12, 07:39 PM
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I kinda question on the A/C size tho...???

Read more: http://www.doityourself.com/forum/ne...#ixzz24QYdbrR1
Ya, in southern Ontario (canada) a newer house which needs 80-90k of heat would require a 3-4 ton a/c. (maybe in a much hotter climate 4-5 tons would be needed)

Older homes with minimal wall insulation need more heat relative to cooling so a furnace of that size could potentially be paired with a 2.5 ton unit.
 
  #36  
Old 09-20-12, 06:50 PM
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Well I finally had it done and professionally installed. AC, gas furnace, hot water heater and blown in insulation with foam air sealing. I've got tons of photos and will post when I have them up.

The guys were very through and the place feels much better. The best part is the humidistat in the iComfort system.

The guys thought it was a 2 day job, it turned out to be a 3 day job!!

Day 1 - 8 guys, 4 guys doing HVAC and 4 guys doing blown in insulation and spray foam air sealing. The other 4 rip out old monster furnace, coils, condenser and duct work. The 3 heat exchangers each one themselves weighed more than the new unit combined. Plan and stage the new units.

Day 2 - 5 guys, install new units and hot water heater, rough in all gas, electrical, some duct work, and PVC piping.

Day 3 - 3 guys, complete install, ductwork, condensate pump etc, clean up and test.

Those were 3 very long days for those guys, I gave them a tip and some beer in the end. For those folks who were thinking our ducts were not capable of handling the air volume of a new system, well... our ducts were massive according to them. They said it looked like we had commerical sized ducts. It took a lot of metal to adapt the openings from the small unit to those large returns and intake.

We'll see in the next year or so how we do on energy savings. According to them we should see at least 25%.


The system is mostly Lennox
SLP98UH090XV60C AFUE=.982 90K BTU
5 Ton AC , 16 SEER, 12.5 EER
Condenser: XC21-060 Coils: L*42/60Y9 AHRI: 5194231
T-stat iComfort, Humidifier Aprilaire 600 and Air Purification PureAir
Rheem Powervent 43VP50E2 50 Gal EF=.67
Attic insulation and air-sealing.
 
  #37  
Old 09-21-12, 05:43 PM
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Sounds great except for the size of the a/c.

480 sq ft per ton in nj? I hope you've got huge windows.

At least it's 2-stage - it'll run on low most of the time.
 
  #38  
Old 09-21-12, 08:02 PM
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I think we have a decent amount and size of windows with an R value of 1 or possibly less. 11 40Wx48H, 4 36Wx36H, 2 100Wx64H 4 small bathroom sized windows and 4 doors with glass panels, main entry door has glass side panels as well. The big 11 windows are standard 8x8 with 9"x11" single pane glass and the rest are combos of the 9x11 glass of various orientation and wood construction. They are very nice but not good on insulation and air sealing. Each of the windows also have an exterior storm window.

After the install we ran the AC and it took a while to cool the whole house down from 76 to match outside temp 72 (it was towards end of the day and cooling down). We ran it for about 1/2 hour. I'll find out next summer if the world does not end in Dec. This past summer it was nasty AC always running yet the house was not getting comfortable, on hot days.
 
  #39  
Old 10-05-12, 07:52 AM
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Photos!

The Oldie
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With the HWH.
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Note the 5' ladder in the top right corner.
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Efficiency upgrade includes more attic insulation and air sealing.
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Old stuff coming out
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Three heat exchanges each over 300lbs.
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Most of it is out only the large 1.5" gas pipe remain.
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Intake
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Return
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Nearly complete
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Condenser XC21 looks can be deceiving and this thing is big
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Flickr
 
  #40  
Old 10-05-12, 10:15 AM
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I think I would have put a steel plate over the hole, put the new furnace on top of that and you would have had a built in bomb shelter....
 
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