[davidmr]

Hey,

I have been doing a lot of reading as we are planning to upgrade our 30yr old furnace & AC. Everywhere I read a 2 stage thermostat seems to be a must. I have had 2 companies quote now and both recommended staying with a 1 stage thermostat letting the furnace timer do the staging.

I understand that the thermostat would control it based on temperature/demand and the furnace is simply a timer. But why do these companies recommend 1 stage? I asked them about it and the first company said that the 2 stage thermostat is more important for if you have larger set backs (at night time or away) otherwise in normal use the thermostat will start in single stage anyway??
I'm wondering how important this actually is in real life/usage?

Other then the thermostat concern the 1st company did a really good job quoting/explaining the work/equipment and was very knowledgeable.. As well he had performed a heat loss calc before hand using average factors for insul,windows,infiltration/tightness for the area. The calc came out about 52k which he recommended a 60k furnace. I have done my own heat loss and came to 50k... house is a 1300sqft bungalow in Winnipeg, Manitoba Canada.

 

[yuri]

I would go with a 60 or 70M and I live in Winnipeg and have the same size house. I have a 70M. Lennox has 45/70/90's. Furnace brands tend to go with 45M and then jump to 60 or 70 no 50/55. 45 is a bit small and will get stressed. I put one in my Uncles under 900 sq ft 35 yr old house and it chugs along nicely. 1300 I would not take a chance on.

2 stage tstat requires a second wire for W2 second stage and most contractors don't like running extra wire. PERIOD. Also jacks up the cost and makes business less competitive when the other guy says stay 1 stage. If you have a extra wire behind the tstat or don't mind paying a bit more to run a new wire if your ceilings are not closed in the basement then a 2 stage tstat is a bit better. I have used the timed on method a lot and never had complaints but 2 stage is a bit better. If you like him and can negotiate a price for a new wire and 2 stage more expensive tstat then go 4 it. $100-200 upgrade I imagine.

 

[davidmr]

Funny meeting someone from winnipeg on here... thanks for replying

I forgot to mention, house was built in 1960.. I'm happy with the 60-70 furnace size as yes the house would have to be really well insulated/air sealed for the smaller size.

Yes a lennox EL296V was quoted, a 70 unit.
As well the york TM9v was quoted by the same company, it's $500 less then the EL296V. It seems york gets some negative comments from people, I realize the install is whats important and determines the final quality, but i still wonder about the reliability of the york?
The modulating york and lennox was also quoted but i don't think they are worth the extra..

Couple other question.
-I have a 4" insulated flex fresh air duct from the outside to the cold air return with no damper. If I plan on running the fan continuously would it be best to put a motorized damper to open during calls for heat or a period of time for fresh air? I feel when its -30C outside the fresh air intake would over ventilate..
-is the existing duct work a concern for noise because of the increased CFM? neither contractor really looked at the existing duct work other then measuring the supply/return vertical plenums.

The existing furnace is an old ICG 115/85 low boy.. big.... lol the a/c is the same vintage, small rectangular box... lol

 

[davidmr]

Yuri, I would like to get a couple more quotes.. Do you have any recommendations for companys to call? You can PM me if you like. I dont have a brand bias.

Thanks

 

[yuri]

I meet all kinds of people here and we have members here from Winnipeg, Ontario, Montreal and as far away as England and New Zealand and Germany. Worldwideweb it is.:smile:

You need to have a Hoyme motorised damper installed on your fresh air pipe. Canadian invention and it only opens when the thermostat calls for heat ( starts the furnace ).

We have big old school ductwork in Winnipeg and with that big old furnace it will be large and OK. Definetly need a 70 as I have the same size 11 yr old house with 3 pane low-E argon windows etc and it ain't too big. Load calcs are fine but the people who made them never spent a Winter here with -40C and a 30 mph wind.:vs_no_no_no:

I put a cheap Goodman 70M in Mom's leaky 1966 1000 sq ft bungalow and your construction is probably similar.

There are quite a few Lennox dealers. Balcaens are a bit expensive but a VERY old well established company. Kirkfield Heating and College Electric are pretty good. The rest, so so or not so.

Rheem makes a decent 2 stage high efficiency furnace. Put one in my Sister's house. Balcaens used to sell Rheem and may still do. A bit louder than Lennox but their circuit boards VERY rarely fail. Good bang for yer loonie IMO.

Lennox has a VERY small neat compact way of venting the pipes outside ( vent termination kit) and Rheem is kinda ugly and same with other brands.

 

[davidmr]

Thanks Yuri..

How about non-lennox dealers? 1 thing that bothers me about lennox is there need for annual service to maintain the parts warranty. I have no problem with the annual service.. but to keep warranty? seems a little shady.. As well I think units like the bryant 926T can be had for less.. just it doesn't have the communicating stuff that the El296V comes with (and doesn't get used with a 2 stage stat)

 

[user_12345a]

There's no excuse to not use a 2-stage stat these days. None!

With wireless, communicating, add a wire (sorry yuri, i know u hate those things) a new wire doesn't need to be pulled.

A smart contractor would offer the 2-stage stat as an option, sell it at a premium, explain the advantages.

An issue with the bigger furnaces in a small house is ductwork. The lennox 66k may want to move over 1000 cfm on a duct system designed for 600-800.

The variable speed blower in some of those furnaces may fail per-maturely if the static is too high.

 

[user_12345a]

efinetly need a 70 as I have the same size 11 yr old house with 3 pane low-E argon windows etc and it ain't too big. Load calcs are fine but the people who made them never spent a Winter here with -40C and a 30 mph wind.

Garbage in = garbage out.

If the inputs are right for -40c, 30mph wind then the load calc will be dependable.

 

[beenthere]

2 stage thermostat will provide a far greater comfort for you then letting the furnace time up to second stage.

do you want your furnace to go to second stage for 1 minute and then shut off. That happens at times when using the furnace timer.

Using a 2 stage thermostat will give much longer run times in first stage heat. Keeping the house feeling warmer. Since it helps to eliminate the cool draft feeling many people get after a single stage, or 2 stage furnace shuts off in second stage.

 

[yuri]

The EL is the Elite series not top end. The SLP is the Signature series with a Communicating tstat and full modulation. The EL has a variable speed ECM motor. Lennox wants people to get their maintenance done and just like a car dealer you need to get it done. I am not going to get into the ethics of it as some other Dudes will come here and get all weird about it. Not sure if Carrier has that policy too. You need to REALLY read the fine print on the warranty of these newer furnaces to see if you need maintenance or it gets void. The parts in the modulating furnaces are VERY expensive and I guess Lennox etc figure they don't want them getting coated in drywall dust and dirt from animals etc and damaging them.

Bryant is owned by Carrier and so is Payne. Good furnaces and easy to get parts for. Lennox and Carrier are the best in the Industry in terms of high end technology and features and they have very deep [email protected] $$. Trane is next and most of the other brands are coming close and have communicating thermostats.

Like I said check out some Rheem dealers. Lennox has some very high end features like working with their zoning system etc but most people don't need that but it is there for a price.

 

[yuri]

There are some cheater, "add a wire" electronic devices to simulate an extra wire. Use at your OWN RISK. They can damage the electronics in circuit boards and especially the modulating and higher end furnaces. Dudes on the net will tell you all kinds of stuff about reviews etc but it is not their house/furnace the unit may damage. Only proper way to get 2 stage is to have a wire or use a expensive wireless tstat.

As far as exact "close" sizing a furnace when you have 6-12 people walking in /out of your house at XMAS with dooors opening etc or throw a party you need some extra recovery capacity in Wpg when it is -40C with a howling wind. People from Ontario etc know NOTHING about our conditions so beware who you listen to.

 

[user_12345a]

I've used add a wire, it works.

better to use a wireless stat or pull a new wire.

As far as exact "close" sizing a furnace when you have 6-12 people walking in /out of your house at XMAS with dooors opening etc or throw a party you need some extra recovery capacity in Wpg when it is -40C with a howling wind. People from Ontario etc know NOTHING about our conditions so beware who you listen to.

How often do you have doors being opened and closed all the time when it's -40? Once every 5 years? Have you ever seen or heard of a properly running furnace operating running continuously, unable to keep up.

Not like you're going to die of hypothermia if the temperature is 65f every few years rather than the regular 70f.

"The undersized furnace" is just an urban legend. They have tons of capacity, put out enormous amounts of heat, using enormous amounts of energy.

70k is 14 space heaters running full blast.

 

[Bob Sanders]

Hey,

I have been doing a lot of reading as we are planning to upgrade our 30yr old furnace & AC. Everywhere I read a 2 stage thermostat seems to be a must. I have had 2 companies quote now and both recommended staying with a 1 stage thermostat letting the furnace timer do the staging.

.

The thermostat is the heart of the system and if you get a good one they can increase efficiency and lower operating costs.

Honeywell makes one which requires only 2 wires to the thermostat

 

[gregzoll]

We went from having our furnace cycle every 20 minutes, to now only running once a day, since we had our house resided. I have a Lennox Signature Series.

Our power bill went way down since we went from the old Aluminum to the Alside Prodigy siding with the foam attached. I have been thinking of swapping out our A/C for a Heat Pump.

 

[supers05]

My preference is York, but it really does come down to installation. Lennox residential stuff is quite reliable. Usually only have problems with plugged drains on them, which is very minor and super easy to fix. Plenty of them around here.

I too have issues with "add a wire" devices. They are made so cheaply with almost no specs published. I've never personally had a problem with one, but I don't install them either. When someone makes a full breakout comms box, produced half decently, then I'll reevaluate.

-30*C at 100kph gusts, sustained 60-70kph winds here isn't fun either, but it is what it is. Local knowledge always trumps internet gurus.

Cheers!

 

[user_12345a]

-30*C at 100kph gusts, sustained 60-70kph winds here isn't fun either, but it is what it is. Local knowledge always trumps internet gurus.

yah it does, as long as it's real knowledge based on real world studies, measurements and verification and not rules of thumb.


The lower the capacity equipment can go while meeting the need in extreme conditions, the better. the longer the cycles, the better. 2-stage and modulating helps a bit with that.

there are contractors where i am putting 80k furnaces in well insulated 2000 sq ft houses with a heat loss of 40-50k, worse yet throwing 2 ton a/c units in 800-1000 sq ft well shaded houses.

the customer may be happy because it satisfies the stat, the contractor doesn't get complaints, but it's neither efficient nor comfortable, nor good for the equipment. Neither the contractor nor the customer will time cycles.

That's "experience" alone will get you, it works but isn't optimal. People can have their experience, licenses, whatever it is and still be lousy.

Every field is the same and everyone just acts out of total self interest. I would never trust even a doctor who recommends a certain procedure or medication; on to the internet i go to get the information that the condescending professional will never give for fear of losing money.

 

[davidmr]

Thanks all for posting.. Been a busy weekend, not much time..

I plan on getting a few more quotes, likely next week as its xmas this week! See how it goes.

I Realize the 2 stage stat will need extra wires. I would have no trouble running new wire my self.. If it becomes a issue I might just upgrade the stat myself, seems like on most furnaces its a switch/jumper to change them to work with 2 stage stats anyway so...

I have been playing with the loadcalc.net site and it seems even with setting the design temp to -40C, a 60k furnace is sufficient, not to mention the other 2 companies recommended 60k's as well, the york dealer said he also does energy audits and did them back when the province was doing them, hes the one that said he did a heatload calc before hand. As for A/C a 2 ton unit is being recommended for my 1300sqft house.

Yuri, I would be happy to have rheem/ruud priced. It seems hard to find dealers though as the manufactures website doesn't have very good dealer/locator pages.. Do you have any experience with Shorty's, Reliable, North 49, 4 Seasons, or Provincal? Again you can PM if you like.

thanks again.

 

[yuri]

Shorty's and Reliable and 4 Seasons are good. I like Reliable and I don't do all the work for my relatives for specific reasons. Had them fix my Uncle's AC and he knows the owner and likes them. The other 2 no way.

60M will be OK. NO way I would ever attempt anything smaller. I saw a 45 in my house and it runs forever. Leaky/drafty houses are very common and how can a load calc determine HOW LEAKY it is. As a business we will never undersize a furnace for that reason and have complaints it won't keep up. If Mom is sick and needs extra heat I won't have her wait 2 hours for it to catch up. Lots of reasons we don't borderline size furnaces in our extreme cold. Lennox used to have 60s and 80s and then went 70/90. 60 or 70 would not make any difference to me as it will run on low fire a lot and only use high fire 1/3 of the time if you have a true 2 stage stat. May only save a very small amount of fuel $$ between sizes/splitting hairs IMO.

Rheem is pretty easy to get parts for in Wpg.

 

[user_12345a]

For a/c how you use it has bearing on sizing.

If you leave it on for a few days at a time at a moderate temperature to kill the humidity, put the smallest that will do the job for longer cycles.

If you need to crank it down, shut it off at night, just want a "cold blast" by all means oversize the a/c.

a/c works best maintaining, running hours on end in the most extreme heat you get, not so much pulling down. The worst thing you can do to a a/c is start it up, and it can take 10-15+ minutes to even reach capacity and efficiency.

The 2 ton is big for 1300 sq ft in canada and could mean setting it to 20-22c to be comfortable due to the poorer humidity control.

Leaky/drafty houses are very common and how can a load calc determine HOW LEAKY it is.

Blower door test, convert cfm50 to cfm natural (or whatever the software accepts), put it into the software.

Not 100% accurate, nothing is, but you can get a decent feel for leakage.

 

[davidmr]

For a/c how you use it has bearing on sizing.

If you leave it on for a few days at a time at a moderate temperature to kill the humidity, put the smallest that will do the job for longer cycles.

If you need to crank it down, shut it off at night, just want a "cold blast" by all means oversize the a/c.

a/c works best maintaining, running hours on end in the most extreme heat you get, not so much pulling down. The worst thing you can do to a a/c is start it up, and it can take 10-15+ minutes to even reach capacity and efficiency.

The 2 ton is big for 1300 sq ft in canada and could mean setting it to 20-22c to be comfortable due to the poorer humidity control.

I am a set it and forget it person. Usually set at 23C and leave it all summer. In the summer we can hit +30C for a week or two, and we really don't have a humidity problem here unless its 30C outside..

I did wonder about the 2 ton a/c size.. The house is 55yrs old so it's not a tight house. I kind of think we are inbetween sizes on a/c's..