What is the size of the current AC condenser? Did anyone do a load calculation? Does the 2000 sq. ft represent the area of the first and second floors?

A 2 ton condenser seems small for a 2000 sq. ft. house especially if the insulation has not been upgraded since 1967. If the duct work is small then it should be fixed to accommodate the correct size condenser. The AC condensers quote are low end. I recommend you get quotes for better models.

The electric work should follow the code. Your contractor should apply for a permit and do it properly.

Hi mike_home,

The current condenser is 2.5 tons (a Rheem High Efficiency model...probably a 10 at best back in the day and operational at a 7/8 now). All the firms did calculate based on sq footage and duct work, though only Company C said that 2.5 would be overkill. Company B stated that the tonnage is actually between a 2 and 2.5, but that the 2.5 would be best. Square footage is 2,150 and yes, that includes the basement as well (closer to 1700 sq ft for top two floors). There's no way we're able to replace the homes entire ductwork...there's nothing necessarily wrong with it, just built for the times. Regarding the tiers, I do have to look at the most budget conscious models unfortunately. All the firms, though, did say that the 13/14 SEER units would probably be best for my size house and length of time ill probably be here, which is about another 7 or so years.

Bhais

Any idea of age and efficiency of old nat gas boiler?

Quote A and B are for identical 2 1/2 ton XB13 AC condenser with matching Tam7 var speed air handler. I do prefer the XR13 over the XB series. Yes, I would consider upgrading to a heat pump model.

The Carrier quote is for low end base series. I would scratch that dealer off my list.

If I knew your rates for nat gas/therm and electric/KWH, I could run some operating numbers for you to compare.

I agree that I would request a load calculation in writing for correct sizing.

Generally you place condenser and air handler on separate circuits. That is the way I would want it done. Bring that old breaker up to code. If this was my home and I thought I was going to upgrade electric service, I would find out what is code from your governing authority. Now would be the perfect time.

IMO

I think the OP has requested the lowest cost option. I don't think the Carrier quote should be rejected because he has quoted a base model. He scores some points pointing out the duct work is undersized for a 2.5 ton condenser. Whether it is the correct size is not clear.

The reason I made the comment about the Carrier quote is it is a low end condenser, not a var speed air handler, clearly not the correct size, and finally more expensive than the Trane. All of the above would cause me to eliminate him from the process.

The Trane quotes/dealers could save homeowner some bux by going with GAM5 high eff air handler but not var speed.

IMO

Hey tigerdunes,

I agree - getting a breaker installed properly and up to code is priority, so whatever path I take that will have to be part of it. I have Washington Gas and NOVEC Electric.

Gas is
First 25 therms 47.91â
Next 100 therms 30.58â
Over 125 therms 25.73â
Gas bill for last month
TOTAL THERMS (TH) USED 122.8
25.0 TH @ $.4796 $11.99
97.8 TH @ $.3063 $29.96
ALL APPLICABLE RIDERS $3.13
SYSTEM CHARGE $11.25
PGC @ $.5026 $61.72
NATURAL GAS SUPPLY SERVICE
LOCAL UTILITY TAX $3.00
ST.& LOCAL CONSUMPTION TAX $2.29
TOTAL GAS CHARGES $123.34

IâÂÂve only been here since September 2011, but IâÂÂve typically averaged 125-130 for gas in the winter, 30-50 in the summer and anywhere from 60-85 in the fall.

I donâÂÂt have the NOVEC rates handy at the moment, but I average $50-$70 most months and anywhere between $110-$160 in the summer.

I believe I'm working with the original boiler for my baseboard radiant heating by the way. The costs weren't ridiculously high as you can see, but I am worried that it could crap out on me any winter now, which is why I was considering the heat pump to potentially help extend its life by offsetting the amount it had to work at all temperatures. Company A said the addition of a heat pump would probably add around $600-700 whereas Company B said that the addition of a heat pump would add $1,175.

The heat pump coupled with the new electric work would be way past my budget, but if it saves me an additioanl $5-6k on paying for a new boiler next year while also dropping some monthly costs, perhaps it's worth it?

Are the original quotes and the additional heat pump expenses in line for the DC Metro area (or in general), in your opinion?

Thanks again for your help!

Tigerdunes,

I follow your logic. I missed the fact the Trane handlers are variable speed. Now I am wondering if variable speed air handlers are being proposed to compensate for undersized duct work. Perhaps I am reading too much into these quotes.

bhals,

Your gas charges are about a $1 per therm. What is your electric rate?

How old is your boiler and what is the condition? A well maintained boiler can last many years. Have you had it serviced yet?

If you are short on funds I think you are better off putting the money towards a better AC and maintaining the boiler rather than buying a heat pump.

Hey mike_home and tigerdunes,

Just obtained my electricity rates for NOVEC.

Distribution Charges:
First 300 = .0210900
Over 300 = .0160900

Electricity Supply Charges:
First 300 = .0973100
Over 300 = .0973100
Power Adjustment Charge = .0134200

I was told that the boiler looks to be original, but I'm not entirely certain and can't verify that unfortunately. Since moving in, I've purchased a maintenance plan to service the ac and boiler annually, and ill continue to keep it maintained.

If boiler is original to a 1967 home, I would suspect efficiency around 70% tops.

I will use that number for comparison purposes until you provide more definitive information.

Rates $1.00 therm for nat gas
$0.12 KWH for electric

I have no idea of the boiler's size, both input and output.

Uh oh, server is down for my fuel comparison calculator site...I will send results shortly...

Results are to be used as a guide only.

IMO

Whenever that information becomes available, that'd be phenomenal to know, thanks tigerdunes.

Bhais

OK here is a comparison and as I explained, it is to be used as a guide only.
The online fuel comparison calculator I normally use is not available because the website server is down.

The savings come from what I believe to be the low efficiency of your boiler not the difference between the fuel rates. If you had a high efficient boiler, the savings would all but disappear. If you don't have any plans on replacing boiler, then I would definitely lean toward a heat pump option.

Inputs
Your Current System New System
Heater Type Natural Gas - Standard Boiler Electric - Energy Star Heat Pump
Fuel Cost $ 1.00 / Therm 0.12 / kWh
Heater Efficiency % 70 380
Dist Efficiency % 95 90
Results
Your Current System New System
BTU*/Unit of Fuel 100,000 3,413
Space Heating Cost
($ Per Million Btu) 15.04 10.28
Operating Cost/year ($) 1,025.73 701.10
By choosing the new system over the current system, you will save (on average) $325 /year in fuel costs.**

IMO

Here is a link that might be useful: Fuel Cost Comparison Caculator

This post was edited by tigerdunes on Wed, Apr 10, 13 at 6:57

Hi tigerdunes,

That's some great information to consider. I know you mentioned you'd recommend a heat pump in my situation, so I got another quote from a larger regional firm who is the subcontractor for a lot of the local Home Depots.

Proposal:
- Lennox Merit 13HPX Heat Pump
- Lennox ComfortSense 500 thermostat
- Lennox Merit Series CBX26UH Air Handler
=$5,190

Everyone else is installing a condensate drain hookup and pump, but this last company perform a R-11 calgon flush to remove sludge from my existing line set, that the existing line set will be re-used in its current condition, and that they offer no warranty on the line itself which I'm not a fan of.

All the other companies are top tier "A" rated on Angies list and this one is only a "B" (with some so-so reviews). I simply wanted to provide this as consideration as well.