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Feedback on HVAC proposal please

We are putting a second addition on our house, a two-storey faux colonial built in 1961. We have an oil-fired boiler that supplies baseboard radiators and hot water. Currently, we have no AC aside from window units.

I have a HVAC proposal from a contractor suggested by our general contractor (the GC did the first addition and we trust and respect his work) to install a heat pump system to heat and cool the addition and, in a second zone, the first floor of the house. The second floor would be uncooled and heated by the existing boiler.

Specifically, the HVAC guy is proposing a 3 ton Carrier Infinity Green Speed air source Heat pump with a variable air handling unit and 5kW heat unit. The cost quoted is $16K including labor and an additional $2K for "2 Thermostat Zone system and duct". He would have to install ductwork for the addition and first floor. The heat pump approach is a result of space being at a premium in the new addition and our desire to air condition the first floor and get rid of its window AC unit.

Questions I have are:

1) Are we asking for trouble cooling just the first floor?

2) What experiences do people have with Carrier? As with most prominent brands, there's a lot negative on the web re Carrier.

3) Is the proposed price in the ballpark? He has given us a range of units of lower costs/SEERs?

4) Is it appropriate to ask to see his calculations of sizing the system?

I can't put my finger on it, but the proposal, which lacks detail on how the work will be done, does not sit well with me.

Re: Feedback on HVAC proposal please

Did you get two other proposals? That is a great way to find out what others think you need as well as compare local labor rates.

Re: Feedback on HVAC proposal please

Yes, you need more bids. You don't need to see the calculations, but you want to be more informed.

Other A/C contractors will probably suggest other units. I usually stay away from Carrier or Lennox, but keep in mind that many brands are made by the same company, which are bought, sold and merge on a regular basis. Choose a middle of the road company (Rheem, Goodman, Heil, Day & Night - are some names). Don't compromise on lower SEER. Other than the equipment, the rest is all labor.

IMO, cooling just the first floor is not the best idea. I would cool the entire house.

Re: Feedback on HVAC proposal please


It doesn't sit well with me, either!

You'll have to give us more basic info before we can give you a definitive answer to your questions.

What general part of the country do you live in (cold climate, temperate, hot)?? What is the total sq. footage of your home, including the 1st & 2nd additions?? What is the current heating OUTPUT capacity of your boiler (on the nameplate at the front of the boiler), and approx how old is it?? Can you provide the boiler model number.

You did well to get an estimate for new heating/cooling equipment, but as the others have noted, you HAVE TO GET AT LEAST 3-5 ESTIMATES FROM 3-5 DIFFERENT HEATING CONTRACTORS----not only to get different written price quotes, but also to get at least 3 DIFFERENT HEATING/COOLING EQUIPMENT COMBINATIONS for your particular house before you can make an informed decision as to: a) which upgrade will be the most cost-effective; b) is it the right fit for your particular house for heating & cooling; c) does it address the geographical climate in which your house is located; d) will it provide you the most bang for the bucks you'll have to spend, and for the least amount you should spend for this project---you have to determine & develop the best "HEATING/AC PROJECT PLAN" that will work for you after having several knowledgeable heating contractors over the house to size up the situation & recommend which way to go on this deal---consult the Yellow Pages under "Heating Contractors", and perhaps also consult a service like Angie's List to view the experience of other people like yourself who are looking for reliable heating/cooling contractors in your area; nearly all heating contractors you may contact specialize in only specific heating equipment, thus, when consulting the "Heating Contractors" section of the Yellow Pages, read all the display ads there to determine a specific specialty, such as hydronics (hot water systems), hot water heating, gas-fired, oil-fired equipment, etc.

If you live in a cold part of the northern U.S. or Canada, most heat pumps may well do an inadequate job of heating a home in these cold climates; I also presently have a forced hot water baseboard/boiler system, and I love it---I wouldn't trade it for anything else; the house is nice & warm all winter, and the system can be easily zoned/expanded using zone valves (low cost, efficient) for different parts of the house so that several separate individual T-stats can be used to control the heat to all different parts of the house; if you have natural gas available on your street, by all means have your oil-fired boiler modified to accept a gas-fired burner, or have a new gas-fired boiler installed as part of the upgrade; natural gas is much less expensive for heating than fuel oil, much of which is an expensive foreign import.

As a starting point, your first possible approach, Project Proposal Plan I, should explore the possibility of using YOUR PRESENT HEATING SYSTEM WITH ITS EXISTING PIPING INFRASTRUCTURE as the starting point for your new system---since you already have the basic boiler, HW piping distribution, baseboard convectors already in place, it is almost always less costly to expand/upgrade the existing system into the rest of the house, as far as heating requirements goes---this assumes the boiler is no more than 10 years old, or so--the present boiler may or may not have enough reserve heating capacity to heat the present house square footage, in addition to the addition---you would have to total the entire square footage of the house, including additions, and multiply the result by approx 35 btu/sq.ft (depending on your geographical location/amount of building insulation); thus, a typical HW boiler at 70,000 btu/hr heat output would be able to heat a residence of approx 2000 sq.ft. (2000 sq.ft. X 35 btu/sq.ft = 70,000 btu/hr)---even if the present boiler is less than 70,000 btu/hr capacity, a larger nozzle may be able to upgrade its heat output, and/or it would probably be more cost effective even to replace the old boiler with a new, more efficient boiler & extend the heating distribution piping (using easy to install hi-temp plastic PEX piping to ferret thru the wall cavities) to hook up additional lengths of baseboard to the new addition, etc.

If the present HW heating system is used, the AC component can be done by installing several ductless mini-split AC units (below) in the existing house & addition (these work very well) & thus you could avoid the additional high cost of installing new heating/AC ducts with a forced hot air/cooling system; mini-splits are installed with the compressor outdoors, so there is no indoor noise with these AC units.

Heating capacity as noted above is usually calculated as a certain number of heating BTUs/hour; cooling capacity is sometimes calculated as a certain number of tons of cooling capacity (1 ton being 12,000 cooling btu/hr); approx 400 sq.ft. of building area can be cooled with 1 ton/12,000 btu/hr AC cooling; the "ton of cooling capacity" dates back to the old ice-house days when tons of ice was the only way to cool things.

As you have other heating contractors come into the house on this project, they may suggest other plans for the heating/cooling remodel----there is for example a Unico system (below) that uses small diameter tubing to install forced hot air/ac tubing to all parts of the house.

There are several ways to skin this cat, listen to all the heating contractors & compare all their plans, then make the choice that is best for you---I'll leave it up to you to write up Project Proposal Plan 2, 3, 4, etc. on this deal.


Re: Feedback on HVAC proposal please

FYI: American Standard is made by Trane - at about 2/3 price.

Same warranty and everything.

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