Anyone buy an AirTap lately?

[woodgeek]

I am ready to retire my tankless coil + oil boiler, and need to put in an plumb a new electric DHW tank. After (too)
much consideration, I am leaning towards the idea of large Marathon tank + AirTap over the GE geospring. I like
the plastic tank idea AND I want to have 80-100 gallons of storage--both for a large supply and to allow slow
recovery from the HP. My issue with the GE is the small size.

The tank will go in a large two-car garage that is semi-conditioned, and I would plan on running it HP 9 mos/year
and straight elec in the dead of winter.

I am not turned off by the design/appearance of the AirTap, but their website does not appear to be very up to
date, and I can't see them selling through any online channel. I can contact them, but I was looking to see if
anyone has had a more recent experience.....

 

[semipro]

Sorry, no input on the Airtap.

I'm not sure if hard water is a problem where you are but it is at our house. We have the Geospring and I'm hoping the heater's design will help avoid some of the mineral buildup problems we had in our former electric water heaters. The Geospring design transfers heat through a coil wrapped around the tank. I'd add that the Geospring has been great so far and we're seeing a drop in our power usage since we installed it. I also love that it dehumidifies the basement.

 

[woodgeek]

Looks like AO Smith makes an 80 gallon all-in-one HP heater with an EF like the geospring. Anyone try it?

 

[woodgeek]

Along the lines of sempro's comment, it appears the new generation of package units have higher performance than the AirTap. Basically, the heatpump COP rating is 2.4 for the Airtap and >3 for the package units. This might jibe with my sense that the AirTap was a 'transient' solution before the big boys got in. I will prob go for an 80 gallon package unit and will post the outcome....

 

[semipro]

Woodgeek,
Just curious. How often do you need 80 gal in capacity As much as that 80 gal model is likely to cost it might be less expensive to install a 40 gal. HP model in series with a standard electric or gas unit with the HP first in line. That way you'll have an effective 80 gal in capacity and the electric unit would only come on if you use more than 40 gal.

 

[woodgeek]

Woodgeek,
Just curious. How often do you need 80 gal in capacity As much as that 80 gal model is likely to cost it might be less expensive to install a 40 gal. HP model in series with a standard electric or gas unit with the HP first in line. That way you'll have an effective 80 gal in capacity and the electric unit would only come on if you use more than 40 gal.

I hear ya. I've been on this fence for a while....

I've got two girls that will be teens in a few years....we have a lot of overnight guests....the wife grew up in an apt building with endless very consistent hot water and has high standards. I've also got limited floor space (in a narrow short garage), but 9' ceilings. I have room for 1 tall tank, but not two small ones I haven't got a quote yet to have the plumber and electrician and permit, but I am in a 'high cost' area and expect that the extra labor of hooking up two tanks will offset the cost difference, etc. The kicker is that from an eng point of view, I think a larger volume will allow us to run more often in 'HP only', so a smaller tank or two in series would have a high operating cost that would erase the up front cost advantage over time, if any.

I guess I'm relying on the KISS principle, and that I don't want to be stuck with a system that disappoints, even from time to time....

 

[Don2222]

Hello Woodgeek

I have a Superstore Ultra 45 gallon tank DHW for my 2 teenagers and get plenty of hot water. You can get an 80 gallon if you need more. Also with the Lifetime replacement warranty means I will never have to pay for another one!

See (broken link removed to http://www.htproducts.com/superstor-ultra.html)

Combined with the Buderus super efficient oil boiler I am using one tank of oil per year for DHW.

Now if you get the Superstore Dual Coil. One coil for Solar Hot water, then you are down to less than a half tank of oil per year!

(broken link removed to http://htproducts.com/superstor-solar.html)

Good Luck!

 

[Don2222]

Hello WoodGeek

Here is a review of the air tap

See > http://www.amazon.com/Airgenerate-A7-AirTap/dp/B001AMU09S

This review is from: AirTap A7 (Misc.)
Though I didn't purchase my Airtap through Amazon, I thought it would be worthwhile to share my experiences here, since I haven't seen too many reviews on the web.

First, my Airtap has been installed for almost two weeks. It came boxed up securely, and arrived with no damage. I paid $699 with free shipping, though I have seen it since for $599 with free shipping. I originally started with a 50-gallon (new) Whirlpool water heater with factory-installed nipples. These were a nightmare to remove (necessary in order to install the Airtap). I ended up exchanging this tank for a smaller (40-gallon) one that didn't have pre-installed nipples.

Installation, other than described above, was relatively easy. Incoming water temperature was 49 degrees, and it took the airtap about 2.5 hours to bring the water up to 115 (my original temperature setting). I soon realized that this unit does not maintain a constant temperature in the tank; rather, it keeps it within a 15 degree range (turns on when the temperature get to 15 degress below the set point). My first shower after some laundry, dishes, etc. was warm, but not hot. I realized that this is because it was at the lower end of the temp range (probably about 100 degrees) due to it turning on just as I started my shower.

I turned the thermostat up to 130 at the recommendation of the manufacturer, and it has helped tremendously. I am generally happy with this product due to it's energy savings. If you are considering one, there are a few things to keep in mind:

1. This doesn't keep your water at a constant temperature, and you may find the temp less than ideal, even after sitting unused all day or night.

2. The recovery time is much longer than with the electric elements/gas burner, which could cause problems if you plan on several showers/high demand in a short period of time.

3. It does make noise when running, so if you are bothered by noise, this may not be for you.

4. Though I couldn't find any stamp on the unit, after reading about it and seeing the printing style on the box, this appears to be yet another product imported from China.

I would recommend a larger tank to allow for more storage (around 80 gallons). This would probably alleviate hot water shortages to some extent.

Overall, I would recommend this water heater. There are others on the market, too. The Airtap seems to be well designed and built, and it should pay for itself in enegy savings in less than a year. We will have to see how durable it is in the long run, though. Just be aware of the few quarks (above) as compared to your existing water heater, and I'm sure you'll find it adequate, though it may leave you out of hot water occasionally. I guess it could takes a little adjustment to the typical American "I want it now" lifestyle.

I heat my home with free wood, so the heat used to heat the water in the winter is also free. Keep in mind that if you use gas, oil, propane or electric to heat your home, you are using this heat that you already paid for once to then heat your water; you are essentially paying to heat the air and then paying to transfer the heat into the water, though it is still much more efficient than using electric elements.

On the other hand, in the summer, you can look at it as using hot air that your AC would normally dump outside to heat your water - basically "free" hot water in the summer (or free air conditioning, however youwant to look at it).

Hope this helps

 

[woodgeek]

Don,

Thanks for the input...I can believe that the SuperStor 45 gal tank indirect fed off your boiler gives you plenty of DHW, primarily b/c of the fast recovery from the boiler.

I am currently using ~300 gal of oil/yr for DHW + standby. (I've already dropped my standby losses by ~250 gal/yr by eliminating a thermosiphon in my hydronic loop, turning
the aquastat down and upinsulating the boiler a little). The main issues are now are the high cost (esp factoring in annual maintenance on the boiler), and the fact that we are
at a 'one shower at a time' mode with the tankless coil. IF I go your route (indirect), I solve the second problem, but not the first. My boiler is also in a small mechanical room
in my otherwise finished basement--I would love to get that finished space back....

I pushed the numbers on solar, which is marginal at my site due to neighbors' tree shading. Right now I can get a 65% rebate (!) on total installed cost (if I qualify for a PA
incentive that requires 80% clear sky--I think I'm 70%). Modelling the output I could expect, I could probably only cover 60-70% of my demand with solar, and the remainder would
be conventional elec backup. Remarkably, a top of the line, 80 gallon ASHP unit (like I mentioned above) would cost less than the after rebate solar, and might only use as much
elec as the solar backup!! If I factor in any maintenance issues on the solar, the long term cost of ownership is likely lower for the HP.

So, it is hard for me to justify the solar. I think I'll skip adding $10k to the PA and US govt expenses this year, and still come out with a cheaper to operate system.

I've estimated a $1100/yr cost for my oil-fired DHW. A HP DHW system should run <$350/yr to operate (even at my currently high elec rates). Simple payback is ~4 years, better
if oil goes up. I love a comfort upgrade that pays its own way.

 

[Don2222]

Hello Woodgeek

Youtube video on Air Tap
http://www.youtube.com/watch?v=Y3pIWahV6W4

I did not ditch the Oil Boiler because it does heat the house automatically if we are away in the winter. The pellet stove would run out of pellets after a day or so.

One thing to check into on HP units is the type of water tank. Glass lined, Stoned Lined, Stainless Steel no Anode.

A glass lined tank will only last 8 years so that can get pricey buying new ones every decade!


If I add another Superstor Ultra tank for Solar then I will be down to approx $100-$200 per year for the oil and never have to buy another tank.


It would be nice to have Superstor Ultra indirect with the heat pump feature!

In the following video the plumber says you can add the Air Tap to the existing water heater!
http://www.youtube.com/watch?v=9uxmceFhq5s&NR=1

So it can be installed on the Superstor Indirect?? That would be cool!! Save Oil !

Video on how the air tap systems work
http://www.youtube.com/watch?v=2uUU1btDLW0&NR=1

 

[woodgeek]

Don,

I agree on the anode....that's why I was looking at the plastic Marathon tank + Airtap originally. The AO Smith package unit I am currently favoring has a higher COP than the AirTap (nice), but the tank is glass (ugh). It has a powered rather than a sacrificial anode, however, so the tank should be good for as long as the HP lasts...15+ years, I figure. It has a pretty thorough warranty with a 10 yr period.

An AirTap on your superstor would pay, esp if you needed dehumidification. Your condensing boiler won't mind sitting cold most of the time, unlike my non-condensing unit.

 

[Don2222]

Don,

I agree on the anode....that's why I was looking at the plastic Marathon tank + Airtap originally. The AO Smith package unit I am currently favoring has a higher COP than the AirTap (nice), but the tank is glass (ugh). It has a powered rather than a sacrificial anode, however, so the tank should be good for as long as the HP lasts...15+ years, I figure. It has a pretty thorough warranty with a 10 yr period.

An AirTap on your superstor would pay, esp if you needed dehumidification. Your condensing boiler won't mind sitting cold most of the time, unlike my non-condensing unit.

Hello

Here is another view on the Dumb Air Tap??

http://www.treehugger.com/files/2010/03/airtap-heat-pump.php

My electric rate is approx 11.7 cents per KWH so an air tap may be cheaper than oil on the indirect!!

Air Tap Install Video
http://www.airgenerate.com/installation_demo.php

 

[woodgeek]

A straight elec heater at 12 cents/kWh is equivalent to ~$4/gallon oil on a cost per BTU basis. Since the AirTap has a COP of ~2.4, it would break even at oil at 4/2.4 = $1.67 gal. If you were using 100 gal/yr at $3/gal for DHW, 150 gallons on standby and your winter BTUs were free (wood), then the Oil runs you 250*3=$750/yr, and the AirTap would cost you 100*1.67 = $167 plus loss = $200.

Seems like the AirTap wpuld pay for itself in 1.2 yrs. There is still a 10% tax credit on HP DHW unit for 2011.

 

[Don2222]

A straight elec heater at 12 cents/kWh is equivalent to ~$4/gallon oil on a cost per BTU basis. Since the AirTap has a COP of ~2.4, it would break even at oil at 4/2.4 = $1.67 gal. If you were using 100 gal/yr at $3/gal for DHW, 150 gallons on standby and your winter BTUs were free (wood), then the Oil runs you 250*3=$750/yr, and the AirTap would cost you 100*1.67 = $167 plus loss = $200.

Seems like the AirTap wpuld pay for itself in 1.2 yrs. There is still a 10% tax credit on HP DHW unit for 2011.

Thanks WoodGeek for that Analysis

Here is more Air Tap information, sounds like the Air Tap does not last as long as the water tanks!! That is the weak spot!
From > http://ths.gardenweb.com/forums/load/hvac/msg0909242420210.html?4

RE: air tap retrofit hot water tank heatpump water heater

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Posted by zippyhvac (My Page) on
Tue, Sep 7, 10 at 12:53

I put one in last year, and according to my kill-a-watt meter, we're paying less than $10 a month for hot water even at our summer electricity pricing, which is 22 cents/kw.

That said, the heart of the technology is basically the same as a $99 window air-conditioner, and the new units are made in China - so who knows what the durability will be.

I paid $699 shipped, but apparently, these units were selling for $499 before the tax credit was announced, and it looks like the price was recently jacked to $799...

The quality seems decent, but it does have a "buzzy" sound when it's running that would be really annoying if you had it near a sleeping or living area.

The install was super-easy for me - I used a new AOSmith 50-gallon electric water heater as the tank (I hooked up the power supply to the standard heater, but turned off the breaker, so I can use the standard elements if the Airtap fails)

Would I do it again? - MEH..I dunno - playing around with the pricing to steal the tax credit seems kind of sleazy, the warranty is really ambiguous - to qualify for the tax credit they had to offer a five-year warranty I believe, but their website now says two years - the new integrated units from GE and Rheem have ten years of coverage, and they have the benefit of being able to use both the heat pump and standard electric elements to give you super-fast recovery if you have guests over, or a huge garden tub to fill.

A quick Ebay search shows the competitors are around $1500~ish, but if you haven't taken the tax credit yet, you could snag $500 in government cheese and nullify the cost difference with a better warranty.

The technology is an excellent idea, and when the competition drives pricing to where it really belongs - (<$600-$800~ish for an integrated unit), I see heat-pump-water-heaters becoming the standard.

Until then... meh... Certainly it can pencil out, but the energy-saving payoff exceeds the warranty which makes me nervous. Solar really isn't any better, and tankless seems to be snake-oil when you look for real savings data, but to each his own...

 

[semipro]

One thing to check into on HP units is the type of water tank. Glass lined, Stoned Lined, Stainless Steel no Anode.

A glass lined tank will only last 8 years so that can get pricey buying new ones every decade!

I believe that's dependent water characteristics, maintenance, etc.

I just replaced a 25 year-old, glass lined, electric, A.O. Smith unit only because I could not remove the heating elements for maintenance. We have hard water and about once every year or two I have to remove the sediment that accumulates in the tank.

I've since cut the tank open and it looks corrosion free. It was my bad on the element issue. I'd replaced them before and should have used some anti-seize compound on the threads or else I overtightened them.

I replaced it with a GeoSpring.

 

[Don2222]

One thing to check into on HP units is the type of water tank. Glass lined, Stoned Lined, Stainless Steel no Anode.

A glass lined tank will only last 8 years so that can get pricey buying new ones every decade!

I believe that's dependent water characteristics, maintenance, etc.

I just replaced a 25 year-old, glass lined, electric, A.O. Smith unit only because I could not remove the heating elements for maintenance. We have hard water and about once every year or two I have to remove the sediment that accumulates in the tank.

I've since cut the tank open and it looks corrosion free. It was my bad on the element issue. I'd replaced them before and should have used some anti-seize compound on the threads or else I overtightened them.

I replaced it with a GeoSpring.

Hello

Yes, the type of water makes a big difference. 25 years is really good for a glass lined tank!!

However the Air Tap only has a 2 year guarantee and it maybe because of that thin flexible copper line heating element that you have to shove all the way into the water tank. Buying it with a water tank that has a longer guarantee does not mean that the Air Tap will last longer!