Moonlighting

[BaldLoonie]

Normally I don't do it but since this was for close friends 15' to the south, I did!

Noisy 60% furnace, 8 SEER leaking A/C, time to do something. But what? With our gas prices, 90% furnace. But 12 SEER A/C? Nope, payback of $20 per year isn't worth it. For same premium as 12 SEER A/C over 10 SEER A/C, I can install a 10 SEER heat pump and save them $200 a year. So that's what we did!

The old furnace, wall behind it is master bedroom.

http://ww2.imagewiz.net/images/hvactalk/125873_furnace-before.jpg

The old A/C, 2 ton and a hair undersized. All the houses in our neighborhood are 2 ton regardless if tiny like mine or 2 story like this one! Note the coil damage from Tom's dog's chain years ago...

http://ww2.imagewiz.net/images/hvactalk/125872_ac-before.jpg

The new 93% AFUE furnace. Donna says much quieter inside. Dedicated low speed constant fan tap helps too. Vented out the side wall due to living area above. In the metal above the furnace is a slot for a 5" media. We're using the Honeywell F200 media, MERV 11.

http://ww2.imagewiz.net/images/hvactalk/125874_furnace-after.jpg

The 10 SEER heat pump. Went to 2.5 ton which is really about 2 1/3 ton these days. Put a sound blanket on the scroll, can't hear it. Just hear the fan. Note the UFO on the wall, used A-S/Trane's BAYVENT200 kit. System is controlled by Vision Pro 8000 stat which is our dual fuel kit. Outdoor thermistor is hiding behind the unit.

http://ww2.imagewiz.net/images/hvactalk/125871_ac-after.jpg

[smokin68]

Nice looking install...even a fresh pad and disconnect. Nice job.

[HVAC Pro]

Nice looking job Loonie. But one question. Did you get it at below wholesale prices? :D :D

[tinner73]

looks nice, and i'm a big rheem fan....what's up with the mini-stilts under the condenser????

[BaldLoonie]

Didn't ask for special pricing, just our usual.

Used only 3" pump-ups for lower profile. Since this is dual-fuel, will turn off above freezing so just needed a little above the pad for defrost drainage. The wind pretty much keeps that area snow free anyway. Blows it around and into my driveway :D

[2hot2coolme]

Verry Nice! Just erks me to see all those finger prints on that nice metal work. Gotta bust out the Fantastic :D

[muskie770]

Nice job. Is this house on a slab? Where does the supply duct go? I don't see setups like that around here. I think the h2o heater may need a new t&p valve. You should get out of the office more often.

[HVAC Pro]

I only use 3" risers. That's all we need here, unless of course we get a foot of snow! For some reason 6" pump-ups look silly for some reason.

[BaldLoonie]

House is on a crawl. That round pipe on the right comes off the supply plenum and goes to the loft upstairs.

He's on borrowed time with the WH. Mine split open 2 years ago spraying all over the garage :(

[dakers]

That's just plum purdy!...LOL Nice job John!

[md master]

I just replaced one of those ruud's (9 yrs old condenser coil rotted out, fins and tubing). Replaced it with a trusty choo choo 12 seer and variable speed.

[ricm]

spanky looking install, Loonie... a bit curious though... the chimney that the HWT vents into is gravity, and there is no tee, just elbows... is that ok in the codes in your end of the globe? Gotta have a tee so condensate doesn't pour back into/onto heat exchangers, even in HWT's here in Penguin country. :)

[BaldLoonie]

No Tees in the flue pipe. Hadn't heard of that one around here. Nobody does it. Is that in a particular code book?

[ricm]

Kwazy Kanadian Kode I suppose. All C-vent connects to the B-vent Chimney via a singlewall or double wall tee... keeps the condensate dripping into a clean out tee. Codes here in most if not ALL Provinces north of your borders... could be due to the Kold Klimate we have. :)

[woods mech]

Looks good man.

[derrick1623]

overall, a beautiful install!
great job!

[Special Ed]

Beautiful, Baldie! But whatcha gonna do when 13SEER becomes the norm as I hear they're gonna do by 2006?

[bja105]

Is the chimney ok for the orphaned "hot water heater?"

[andrewd33]

How much are the electric rates in your area that a 10 SEER hp will save more $$ than the 12 SEER cooling. I am in North NJ and I like that plan, I would probably have to do the 13 SEER HP over the 14 SEER XL14I str8 cooling.

[BaldLoonie]

After the first 500kwh a month, which is taken up by lights & appliances, next 500 is a little over 4 cents. After that it drops to 3 cents for electric heat or dual fuel users.

For my friends' house, probably looking at saving $20 a hear for 12 SEER A/C over 10 SEER A/C but upwards of $200 a year for dual fuel as our gas is hovering around a buck a therm. Savings may be a bit less with the 90 over an 80 but still considerable. Last winter I used my gas very little since I like it cold. Sometimes running the pump alone down to 10 above. Gas bill dropped considerably, electric bill went up a few bucks.

[BaldLoonie]

The other 2 questions,

when 2006 rolls around, we'll have no choice on SEER. Until then, with our very low rates and mild summers, there is no economic payback for high SEER. Just because today's units will be obsolete in a bit, doesn't mean they aren't the best bet for our customers today. For many, the new regs will be quite the hardship meaning many may have to go without air or do highside only changeouts which we know will be a mistake.

No chimney, small b-vent has no trouble venting just the WH.

[andrewd33]

Where on earth does anyone pay 4 cents a kW for electric. We are paying 10 cents for the first 600 kW then goes to around 11 in the winter then in summer goes to around 13.5 cents. Just across the river in NYC they are paying con-ed rates of 18 cents/kW plus 8.75% NY sales Tax. Makes you really think about even turning on lights.

I have been trying to get the people in my co to let us start selling a heat pump / furnace package. They say it won't pay off up against a 90% furnace. With the price difference they charge I can see why it won't pay off. Also my boss (Sales mgr) tells me you can't use anything less than an XL13i in the winter for heating because of the lid. He says without the lid on the Trane unit it will cause the fan blades to collect ice and get out of balance, I say there are a lot of heatpumps in cold climates without lids I can't see it being a problem.

How do you calculate the energy savings easily. is there a simple formula or calculator you can use?

[BaldLoonie]

Our supplier used figures from the electric utilites for his data on dual fuel. With straight cool figure approx kw usage based on capacity, SEER, cooling load hours and electric rate.

This job was 2.5 ton 10 SEER though 2 ton load.

2.5 ton 10 SEER uses 3kw per hour
2.5 ton 12 SEER uses 2.5 kw per hour
we have 1000 hour cooling season for the average user

diff is 1/2 kw per hour

1/2 kw x 1000 hour cooling season x .04 = $20 smackers per year savings. Since unit is a bit oversized, that savings may be a bit high but since these people use their air more than average, that balances it out.

Not easy with dual fuel. Our utilites have programs that take into consideration the rate structure of a lower rate over 1000 hours too.

We get to -10 each winter with snow. We do just fine without covered tops on our heat pumps! Usually if it is cold enough to snow heavily, the heat pump is on anyway so snow doesn't collect on the fan. In my dual fuel situation, it can as I go to gas in a snowstorm.

[andrewd33]

Based on the fact that we pay about $1.10/ therm for gas

1 therm of gas = 92,000 btu's based on 92% furnace.

I would guess I need to look at the temperature performance curve of the different heat pumps to determine the break even point. I guess the real savings are in the mild weather between October and December and then again in the end of March through the begining of through May/June. I just wonder if the 10 SEER Heat pump out performs the 90% gas furnace in the milder weather and could give a better payback than going to the 12/13 SEER. Also Keep in mind we get the 13 SEER rebate out of a 12 SEER XR12 unit by matching with a Superior Coil that matches up to 13 SEER. That Rebate is $300. I was trying to calculate the comparison of the heat pump and the 90 but was doing it at the performance of 30 degrees outside. I think with a 16 SEER it came out to 90 cents per 92k btus and the gas came out to 1.10, but the 16 SEER heat pump is quite pricey. If you could come out ahead around here by going from 12 SEER A/C to 10 SEER HP that would be great.

[BaldLoonie]

If my math is accurate, you are looking at 1.20 in gas and probably 10 cents in electricity to get 100,000 BTUs out of a 92% gas furnace with your rates.

Now, looking at a Heritage 12 3 ton with TWE040 rated at 8.86 HSPF (not bad!) to get the same 100,000 BTUs at various outdoor temps, here's what I came up with.

7 degrees = $1.72
17 degrees = $1.38
27 degrees = $1.19
37 degrees = $1.06
47 degrees = 85 cents

So with your rates, the heat pump would be cheaper to run from 27 on up

Figure we have the same gas costs, here's what I come up with using 4 cents per kwh

7 degrees = 63 cents
17 degrees = 50 cents
27 degrees = 44 cents
37 degrees = 38 cents
47 degrees = 33 cents

Looks like we are cheaper with the heat pump regardless of outdoor temp. However, with typical sizing 27 would be about the point where the heat pump's output matches the heat loss of the house and either shutting off the pump or at least running some gas would have to be done.

This shows just how big the savings potential is here for dual fuel. With the US average of 8 cents per kwh, double those figures and above 7 degrees, a heat pump still saves some money. Many areas spend most of the winter at or above freezing so even with US average rates, some healthy dual fuel savings are possible.

[selfemployed]

Nice work.

[go_redskins]

Baldloonie wrote:

If my math is accurate, you are looking at 1.20 in gas and probably 10 cents in electricity to get 100,000 BTUs out of a 92% gas furnace with your rates.
...
Figure we have the same gas costs, here's what I come up with using 4 cents per kwh

7 degrees = 63 cents
17 degrees = 50 cents
27 degrees = 44 cents
37 degrees = 38 cents
47 degrees = 33 cents

Looks like we are cheaper with the heat pump regardless of outdoor temp. However, with typical sizing 27 would be about the point where the heat pump's output matches the heat loss of the house and either shutting off the pump or at least running some gas would have to be done.

If your electric rate is 4 cents/kwh and then drops to 3 cents/kwh, wouldn't you have been better off going straight electric heat as backup instead of a 92% gas furnace.

At 4 cents/kwh, electric heat is just

100,000 BTU * (KWH / 3412 BTUH) * $0.04/KWH = $1.17 per 100K BTU

At 3 cents/kwh, electric heat is just

100,000 BTU * (KWH / 3412 BTUH) * $0.03/KWH = $0.88 per 100K BTU

And the cost of equipment would have been lower too.

[BaldLoonie]

Only drawback would be having a 200 amp panel put in for the electric furnace. Around here, all electric homes with a good HP do have lower overall bills than gas/electric, especially when you figure $120 a year just for the having the meter.

[ricm]

Here in Middle Alberta, we are paying 7 cents per KWH. Even though I burn one light, and hardly ever use the electric cook stove... I still get hit with $50.00 to $60.00 monthly bills.

Fortunately I live in an appartment these days, and don't have to pay for heat. Average home owner here pays about $200.00 monthly for natural gas.

I don't recall what the actual rates are for the gas though.

Heat pumps, and Oil furnaces (sometimes electric furnaces) are common in Eastern Canada. Out west here, we used to get about $30.00 monthly gas bills a few years back, when the Alberta Govt. controlled it. Since it's been privatized... We almost got nose bleeds from how quickly the price rose. And we are sitting on the biggest natural gas reserve on the Globe! :eek: