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Topic: Heating and Cooling Guys? (Read 1908 times) previous topic - next topic

Heating and Cooling Guys?

I figure its worth a shot to ask this here, my T-bird/Cougar brethren have rarely lead me wrong.  Wondering if anyone is an expert on home HVAC systems?

My house has a furance that was installed in 1986.  It is a Lennox "Pulse" model that I have honestly never had any problems with.  The only thing I know that has ever been done was a new heat exchanger in 1998 (found record in a file).  I have lived here since 2007 and have honestly never had any service done until last year.  I had a local guy look at it and he said it was showing its age and needed replaced.  I had another guy look at it for a 2nd opinion and he said it looked fine!  He did tell me that there is a control board of some sort that will eventually fail and would cost $500-$600 to replace.

From what I have read, the Lennox pulse furnace is one of the most efficient ones ever made (97% efficiency) and are better than most sold today.  I hate to remove it for something vastly inferior!  I just am not sure if a 1986 model year furnace would be on its last leg??  That seems to be pretty old to me, but I'm no expert on the matter.

The problem I am facing is that while the furnace has been working great (for now), its the A/C unit that has been causing problems.  Every summer it quits on me 2-3 times, especially in extremely hot conditions.  Last thing I want is my A/C to poop out on a 100+ degree day with a 10 month old baby in the house.

Therefore I have gotten a couple of price quotes locally.  One quote is for a Ducane brand 95% single stage furnace with a 16 seer A/C unit.  The other is for a American Standard 95% eff furnace with 15 seer A/C unit.  Are these two brands comparable?  Would they be comparable to the Lennox I have now?  Should I just wait for my AC or furnace to totally  out or be proactive and get them replaced now.  I do want to sell this house in a few years to move more into the country and want to do what I can to help make it more sellable.  I did buy the place right (from a relative) and with the intention to fix things up.  To me, a new furnace/AC makes a good selling point when I do put it on the market.

So, anyone have advice for me?  Thanks to anyone that can help me out!!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Heating and Cooling Guys?

Reply #1 –
I'm no heater/ A/C expert but, it's common for A/C's to go out during Hot weather because everyone is using them. If it isn't related to outages I think if you were to fix it now it would be better, because when the heat picks up everyone will want to charge up the a** to fix it. Just my opinion though.
[SIGPIC][/SIGPIC]

Heating and Cooling Guys?

Reply #2 –
how many ton unit is it and sq footage of house and do you have split levels?

mitsubishi splits are about 5k a pop  equipment only and max out at approx 3.5ton, they dont have 105degC condensor coil options tought.
Best brands are out there
Liebert 5Ton approx 5800.00
Bard 5ton approx 5400
Aaon dont ask how much
Addison, again dont ask

then there are Carrier, Lenox and Trane. 

I engineer most all brands on my projects as well as DC plants, generator systems, alarm systems, hydrogen detection, fiber entry, utility power upgrades ect  and to tell you the truth, you have a big choice to make here in brand if new is what you want.

Personally, i would search out all the documentation on the system and start going through it with a fine tooth comb then price up the pieces parts that are due for replacement.  The system you have is obviously a heat pump system but how about the refrigerant, was it converted and if so, you may want to understand how this might adversly effect the compressor over time.

the ideal location for your condensor is in the north eastern side of the home in order to maximize the ambient temp rating of your condensor.

You could get a liebert 5T wall mount unit , combines condensor and compressor was one unit, integrate it into your existing duct as long as the duct is large enough and all static pressure losses are acconted for.
Static loss is when there is a bend or a turn, reduces the CFM of the blower.
You could litterall install a Liebert or a Bard wall mount yourself, just need electricity, approx 60A 2pole.

You could get two of them and us a Lead / Lag controller , integrate zone temp sensors (approx 200 ea) , integrate smoke detetection as well and link that sense circuit to your existing ADT home alarm system if you have one. 
These "newer" HVAC systems are typically SNMP ready and from there you can "get an app for that"

Your gonna spend approx 6k for a system then approx 1500 to 2500 installation anyway if you go new, this is not going to be a good choice to make but one worth considering.

Id start learning the system you have then start dropping in by all the hvac shops near you and ask them for compatible parts.

Right now what you can do is clamp on to the hot legs of the unit in your electrical panel and find out how many amps each leg is pulling when the day is around 1pm and temp outside is hot.

check both the condensor feed and compressor if separatly wired.  It would be nice to learn that a poor connection somewhere is causing high current drawn and your hitting rotor lock or freeze up due to a minor malfunction or loose connection.

Heating and Cooling Guys?

Reply #3 –
What are you meaning by the A/C quitting? Is it that it can't keep up or that it had to be repaired?

If the furnace is able to blow enough temperature controlled air throughout your home when the system is running properly then I would not worry about the furnace.

The A/C has an evaporator coil that is in the metal sheeted trunk above or below the furnace (upfire or downflow) and can be replaced apart from the furnace.  The 2 copper pipes (little is high pressure and bigger is low pressure) carry your refrigerent to and from the condenser coil (unit) outside.  All this is controlled by your thermostat and the smart board in your furnace.

How old is your thermostat?  A good White-Rodgers simple digital or programmable thermostat runs $30 on up and are simple to use.  Also, make sure to keep your furnace filter changed on a regular basis (30-60 days) and hose off your condenser unit coils/fins to remove grass, leaves, spider webs etc.  All these things should help you keep that unit from having to work extra-hard.

If your furnace works fine and has a newer heat exchanger I would not worry about replacing it. How old is the A/C unit? Maybe your old one is tired and lost it's efficiency.  I would think any brand is compatible with your furnace, just call around and get estimates and see who has a the best warranty and service contract.

Good luck and make sure to have a carbon monoxide detector close by your furnace just to be safe!

Heating and Cooling Guys?

Reply #4 –
Also forgot to point out , 410a was in the making to be used for phasing out r22 when I was in HVAC school in 2005 along with 13 seer being the minimum on the market at that time. 

410a is not as forgiving with contaminants in the refrigeration system, over time as r22 and also runs at much higher pressures than r22.  Something to think about if you have small children that may play around the condenser unit and accidently poke a stick into the unit or if you develop a leak in the system, you will lose a charge much quicker.

Tim

Heating and Cooling Guys?

Reply #5 –
Like the other guys said, A/C is independent from the furnace. I'd just look into that side of it and forget the furnace until it's an issue.

Something to consider would be a heat pump for A/C. It's a great air conditioner and also cuts down on your gas bill in winter. For instance, last winter was so mild I used only 1 tank of fuel for the whole winter. The heat pump handled it most of the time. You can adjust the temperature at which your furnace takes over based on your fuel cost vs. electric rate. Mine switches right around 35 if I recall.

I got a new one last year for about $2500 installed with a 10 yr parts and labor warranty. If you need a new plenum it'd be more, but mine was replacing an existing unit.  I did some haggling to get that price.

Heating and Cooling Guys?

Reply #6 –
Quote from: flylear45;392717
Like the other guys said, A/C is independent from the furnace. I'd just look into that side of it and forget the furnace until it's an issue.

Something to consider would be a heat pump for A/C. It's a great air conditioner and also cuts down on your gas bill in winter. For instance, last winter was so mild I used only 1 tank of fuel for the whole winter. The heat pump handled it most of the time. You can adjust the temperature at which your furnace takes over based on your fuel cost vs. electric rate. Mine switches right around 35 if I recall.

I got a new one last year for about $2500 installed with a 10 yr parts and labor warranty. If you need a new plenum it'd be more, but mine was replacing an existing unit.  I did some haggling to get that price.

 
If his winters in Indiana get as harsh as they do here in Illinois, I don't know if a heat pump would be enough.

If I recall do they use electrical elements as secondary heat source?

Heating and Cooling Guys?

Reply #7 –
Thanks for the response guys.  I am a total newbie when it comes to this sort of stuff and need all the advice I can get!!

The A/C is leaking refrigerant and will freeze up in hot weather when it is working hard.  So far this year its been good to go, but the last two years I have had a lot of problems (it quit on me last year in 100 degree weather with a 9 mo pregnant wife, that was not good lol).  This week will put it to the test as its supposed to be upper 90's through the weekend.

I have had a couple of guys tell me that a new A/C won't work well with this older type furnace...but maybe they are just trying to sell me a new one?  From what I could understand, you would have to go with the low end A/C unit to be compatible with this old furnace?  Thats one reason I am looking into replacing the furnace.  I also am trying to make the house more attractive to potential buyers for when I sell in a few years.  The newer furnaces have a 10 yr warranty, so I figure that would help sell the house compared to the 30 year old unit I have now which could  out at any time.

Quote
Something to consider would be a heat pump for A/C.


I do not have a heat pump now.  I am afraid to go that route in case it would not be enough to keep up in some of our cold winters.  I have heard mixed reviews from co-workers and friends.  Some claim a huge savings while other say in very cold weather it made their bill skyrocket.

Quote
How old is your thermostat? A good White-Rodgers simple digital or programmable thermostat runs $30 on up and are simple to use. Also, make sure to keep your furnace filter changed on a regular basis (30-60 days) and hose off your condenser unit coils/fins to remove grass, leaves, spider webs etc. All these things should help you keep that unit from having to work extra-hard.


Thermostat is about 3 years old.  Not sure of the brand though.  I do change the filter about every 2 months.  I also wash off the AC occasionally with a hose (probably need to do it again, havent done it this year yet).

The pricing I have is:
1.) $5500 for a Ducane 95% efficiency furnace, single stage, w/thermostat, 16 seer A/C, includes labor and tax. 
2.) American Standard at $6200 (includes labor, tax) for 95% efficiency furnace, thermostat, psc blower (whatever that means), 13 seer AC unit.

My house is single level 3 bedroom, 2 bath, with full basp00get and is around 2000 sq ft (not counting the basp00get).  I do know that the guy pricing American Standard measured the house to get the sq footage before he priced.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Heating and Cooling Guys?

Reply #8 –
Quote from: 50tbrd88;392727
I do not have a heat pump now.  I am afraid to go that route in case it would not be enough to keep up in some of our cold winters.  I have heard mixed reviews from co-workers and friends.  Some claim a huge savings while other say in very cold weather it made their bill skyrocket.



The idea with a heat pump would be to use the gas furnace as the backup heat source, not the expensive electric resistance heating. The heating it provides is a bonus savings in the milder parts of winter.

Whatever you do, I hope it works out well for you!!

Heating and Cooling Guys?

Reply #9 –
Thats quite a chunk of change, but it is an all new setup.  I guess it depends on how long you are staying at the home and if you can get any extra out of the house with an all new system.

The "squirrel cage" fan will be pumping your air through your cold evaporator coil in the trunk plenum to cool your home.  If this is not able to pump enough volume through to cool the home than the system would be mismatched or your furnace would be too small for the home.

A good heating and cooling technician/salesman should be able to match an ac unit to match your exixting furnace if you choose to go that route, to save money. I would at least see what the difference in price is out of curiousity for just the condenser, evaporator lineset and install to your existing furnace.  It would also let you know if they are giving you a package deal or not on the two quotes you have already.  You can always haggle a little bit, kind of like buying a car, there are alot of dealers around to choose from.

Good luck and stay cool!

Heating and Cooling Guys?

Reply #10 –
Quote from: flylear45;392757
The idea with a heat pump would be to use the gas furnace as the backup heat source, not the expensive electric resistance heating. The heating it provides is a bonus savings in the milder parts of winter.

Whatever you do, I hope it works out well for you!!

 
From what I've been told, when the temp drops low enough for the furnace to kick in, the thing has to work harder to keep up??  Maybe the folks I talked to who had high bills had an electric furnace then??  I know nothing about this stuff, lol.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Heating and Cooling Guys?

Reply #11 –
Well the idea of a secondary heat source would be it would take over to help the primary.  lets say the house is 65degrees and thermostat calls for 70, furnace just has to kick in to warm house 5 more degrees.  Its taking that warm air through and just heating it up.

Heating and Cooling Guys?

Reply #12 –
Quote from: 50tbrd88;392840
From what I've been told, when the temp drops low enough for the furnace to kick in, the thing has to work harder to keep up??  Maybe the folks I talked to who had high bills had an electric furnace then??  I know nothing about this stuff, lol.

Not quite. When it gets colder than 35 degrees my heat pump "hands off' to my oil furnace. At that point the fan is the only part of the shared system that is working. You will notice when the heat pump isn't making a lot of hot air. the fan runs longer. The trick is in 'tuning' the system to get the most out of each system. In effect it is a hybrid. You have heard that word a lot when it comes to energy efficiency.

 The heat pump in my house IS the air conditioner. As a bonus, it helps heat with lower cost heat in mild parts of winter. The horror stories come from those that use electric element heat as primary heat in cold temps. It sucks for efficiency. Your high efficiency gas furnace is a MUCH better source of heat then. A good thermostat will be able to be programmed to take advantage of your specific combo to give you optimum efficiency. I have been using a hybrid for 25 years and love it FWIW. the thing is, they cost so little more than JUST an air conditioning unit, I say......why not??

Heating and Cooling Guys?

Reply #13 –
One last thought. ( If that's even possible with me LOL.) Sizing is CRUCIAL! Too big a unit is NOT better. As stated earlier, the unit will freeze or cycle too often if too big. Your A/C pro has to do a study of your house to figure the correct sizing for your compressor and evaporator coil, or it will not function properly. It's just science.

Heating and Cooling Guys?

Reply #14 –
Quote from: flylear45;393050
One last thought. ( If that's even possible with me LOL.) Sizing is CRUCIAL! Too big a unit is NOT better. As stated earlier, the unit will freeze or cycle too often if too big. Your A/C pro has to do a study of your house to figure the correct sizing for your compressor and evaporator coil, or it will not function properly. It's just science.


Amen to that, make sure the new installer does there homework on your home to properly fit and match a system to your home. Size of home, location of your furnace, amount, location and size of cold air returns and supply ducting and type of insulation in the home and attic should all be considered to best fit your home with the right compressor, evaporator and furnace.