Archive for Home Improvement

Adding a Programmable Thermostat to Mitsubishi Mr. Slim Heat Pumps

As part of an ongoing energy upgrade of my 1930 home, I had four Mitsubishi Mr. Slim mini-split heat pumps installed (three MUZ/MSZFE09NA 9000 BTU units, and one MUZ/MSZ12NA 12,000 BTU unit.)

If price had been no object, I probably would have gone for Waterfurnace’s (TSX:WFI/OTC:WFIFF) Series 7 or Climatemaster’s Trilogy ground source heat pumps,  but my home’s existing heating is an oil boiler and radiators, and the Series 7 would require installing air ducts throughout the house.  The mini splits have the advantage that the refrigerant lines can run up the outside of the house, making them much easier to retrofit.

The geothermal systems I was quoted would have cost $50,000 to $60,000 (minus a $500 rebate from my utility), while the mini-splits cost $15,500 (minus a $2000 rebate.)

Because I’m also doing extensive insulation and air sealing, my heating bill is only about $2000 a year, even using oil at over $4 a gallon.  After using the air source heat pumps for two months, I expect these mini splits will approximately halve that.  The geothermal system would have done better, but even if it cut my heating bill by an impossible 100%, it would have taken 25 years to pay back my investment.  The mini-splits will have an estimated payback of about 13 years, which is not great, but both they and the geothermal system have the added advantage of giving me efficient air conditioning in a home that did not previously have it.  In New York’s Hudson Valley where I live, A/C is only useful for about 1 month a year, but it’s sure nice to have during that hot and sticky month!

In any case, I’m happy with the mini splits except for one thing: they have very limited programability, something I did not realize before I had them installed.  The best you can do with the included remote controller is set them to turn on and off once each during a given 24 hour period, and you have to manually set this up every day to use them that way.

There is an available programmable thermostat (Mitsubishi kit MHK1), but it is intended to be installed with the heat pumps, not after the fact.  My HVAC contractor offered to install them anyway, but he wanted $350 each, or a total of $1,400 for all four.  That’s not unreasonable, since the MHK1 retails for  $243, but it was more than I was ready to pay.

Since he told me he would have to figure out how to do the install from the documentation, and I had seen him struggling with the translated-from-Japanese when he was trying to figure out what was wrong with one of the units when it was first installed.  (It turns out two of the wires were reversed.)   I’m decent at that sort of thing, so I decided to give it a go myself.

There was one point where the documentation was completely unhelpful.  I figured it out eventually, but the rest of this post should save you a lot of trouble if you’re trying to do the same thing.

Installing Mitsubishi Programmable Thermostat Kit MHK1 on Mr. Slim Heat Pumps

  • Tools needed: Phillips screwdriver
  • Time required: 15 min (experienced) to 1 hour (first time).

Manual

Not only does the manual say to install the data cable before the heat pump is installed, there is no information about where the “CN105″ connector on the control board is to be found, or even where the control board is.  None of the documentation I found online was any more helpful.  Eventually, I figured out where the control board and CN105 connector were, and how to get to them.  Here’s how:

Turn off the power to your heat pump at the circuit breaker.

Remove the horizontal vanes

Remove the horizontal vanes

remove screw covers

remove screw covers

Covers removed... screw locations circled

Covers removed… screw locations circled

After 2 screws holding the unit cover are in place, the cover can be removed by pressing in around the edges, and popping it off.

When the cover is removed, the bar containing the i-see and indicator lights may swing down.

When the cover is removed, the bar containing the i-See and indicator lights may swing down.

Don't panic, just hang it back on the two plastic hooks like the one shown here

Don’t panic, just hang it back on the two plastic hooks like the one shown here

Now remove the Emergency operation switch by pressing on the tab shown here

Now remove the Emergency Operation switch by pressing on the tab shown here

You can now remove the screw that holds the control board cover

You can now remove the screw that holds the control board cover and remove the cover to access the board.

These wires, too.

You’ll need to disconnect this wire to slide out the control board.

SONY DSC

This wire, too.

Now you can gently slide out the control board and connect to the CN105 port, shown here.

Now you can gently slide out the control board and connect the control wire to the CN105 port, shown here, circled.  It’s located in the bottom back corner of the control board.

You’ll want to snake the control wire through the unit so that it’s hidden when everything is installed.   Make sure you’ve left plenty of slack on the control wire, so it does not pull off when you put the control board back.

Now you can reverse the above process to put everything back where you found it.

You can now connect the wireless receiver, and proceed as described in the installation guide.

You can now connect the wireless receiver, and proceed as described in the installation guide.

The rest of the manual was no harder to follow than these things usually are.

It took me a few hours to figure this out… hope I can save a few readers the aggravation.

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How a Storm Can Help Your Home’s Energy Efficiency

I was fortunate last night here in New York’s Hudson River Valley, unlike many neighbors who lost power, and the people in NYC and New Jersey who had to deal with an unprecedented storm surge of 13.88 feet and winds (video) which NYC utility Con Edison says caused the largest power outage in the company’s history.

While the high winds around me last night were causing power outages and worse damage, I was going around with a screwdriver and outlet cover gaskets to stop the air leaks which I could easily feel with my bare hands.

It was also a good way to keep my mind off the storm.

Sealing electrical outlets and switchplates  is one of the cheapest and most effective measures you can take to improve your home’s energy efficiency, as cost-effective as CFLs, with the added bonus that it makes your house less drafty.

Sure, it’s better to simply have the whole house spray foamed, as I recently did in my basement (see pic) , but that is a big job, and usually requires existing insulation to be removed.

These walls have been foamed, and the workers are in the process of shaving off the excess that extends beyond the studs.

My house, which was built in 1930, has an old urea-formaldehyde based foam insulation in the walls which was probably installed in the 60s or 70s.  The product was banned in 1982.

Over time, that foam shrunk and now does little to prevent air movement in the walls, and I can only replace it by tearing the walls open.

Formaldehyde based foam revealed during bathroom renovation

Hence, I’m taking smaller steps with air sealing.

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Hedging the Value of a Home with S&P/Case-Shiller Futures

I’m currently looking for a rental house in Fairfield County, CT, but have been totally disgusted with the rents… they are high enough that it currently makes more sense to buy (in terms of a basic time-value of money calculation)… if you assume that you’re going to stay there for a few years and housing prices won’t depreciate further in the meantime.

Unfortunately, I’m not comfortable assuming that house prices will not drop further, so I looked into the idea of hedging my expected exposure to the New York housing market with a short position in futures on the S&P/Case Shiller New York Real Estate Index.

These Futures contracts trade on the CME with a notional value of $250 per point. With the index currently trading at around 170, each contract is enough to hedge $42,500 worth of housing in Fairfield County (which is included in the calculations of the New York index.) So a $425,000 generic house in the New York area could be hedged with 10 contracts. (In fact, you’d probably need 20-30% more than that, because profits and losses on the futures would be taxable, while capital gains and losses on the house would not be, at least up to a limit of a $250,000 gain if you had lived in it 2 out of the last 5 years.

The problem lies in market liquidity. It currently looks like the longest dated futures are trading at 170, which means that they are predicting the market will not rise or depreciate significantly over the next four years (although shorter-term contracts are predicting a short-term decline followed by a recovery. But to hedge that $425,000 house if you’re subject to a 30% tax rate, you would need about 13 contracts. As I look at the quotes today, the current bids for even the closest November 2010 contracts are for only 3 contracts, and the bid-ask spread is 10 points, or $2500 per contract.

There is no bid for the November 2014 contracts that I’d be most interested in, meaning that I can be confident that my order to sell would move the market significantly. Assuming unrealisticly optimisticly that an ask for 13 November 2014 contracts moved the market only as much as the spread on the closest-in contract, that means a transaction cost of 10 x $250 x 13 = $32,500, which is about a full year’s rent in a comparable house.

I’m going to have to file this one under "it seemed like a good idea at the time."

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Fannie and Freddie Trip Up PACE Financing Program

Bad news for both her economic stimulus and energy efficiency. The New York Times reports that PACE (Property Assessed Clean Energy) financing for energy efficiency improvements, for which $150M in stimulus money was set aside is running into a roadblock from another arm of the government: the mortgage agencies Fannie and Freddie.

See the full article here: http://www.nytimes.com/2010/07/01/business/energy-environment/01solar.html?_r=1&pagewanted=1&hp

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How to look for an Energy Efficient Rental (or resale home)

Does it seem totally unfair to you that the young, who are typically much more environmentally aware, are often stuck living in cold, drafty, unhealthy, and expensive to operate rentals, while it’s the old and the wealthy splash out on gigantic mansions with multiple low efficiency furnaces and air conditioners?

It does to me. Well, if you’re one of those green renters, you can do something about it. I’ve put together a checklist to use that can help you sift out the efficient buildings from all the cold, drafty ones.

Since it’s not really about stocks, I sent it over to Jetson Green as a guest post. But if it’s stocks that might benefit from the trend in energy efficient homes you’re looking for, I list several in the intro I wrote for it at Alternative Energy Stocks.

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Greener Money at Smart Energy Living

I’ve accepted an offer to write an investment column for Smart Energy Living, a quarterly magazine put out by the Colorado Energy Science Center, which focuses on clean enrgy solutions for homowners.

I’ve been a subscriber since I arrived in Colorado in 2005, and I find them an excellent resource for home imporvement. They have plans to go national with the next issue, and recruiting me to write for them is part of that move.

The column will tentatively be called “Greener Money” and will focus on helping small investors green their portfolios.

You can sign up for a free copy here. If you read my blogs, there probably won’t be a lot that you’ll learn from my columns, but if you’re interested in energy efficienct home imporvement, it’s well worth getting for the other articles.

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Denver Tour of Solar Homes Sneak Peak; links to National Tour

Preview the Denver Tour of Solar Homes Online


The Denver area Tour of Solar Homes takes place in less than a month, and this year you can preview some of the buildings involved online. 
Check out the Sneak Preview on the right-hand side of the
Tour of Solar Homes page on the CRES Web site

.

 

The 2007 Tour of Solar Homes will take place on Saturday, October 6 in Denver and most locations around the state.  However, some of the activities are slightly different. 
The Boulder tour will take place on Saturday, September 30. 
And the tour in Pueblo will span two days: October 6 – 7. 
See a complete listing of solar home tours in Colorado on the American Solar Energy Society Web site.

 

National Solar Tour

 

Outside of Colorado, people you can find tour in your own community by visiting the National Solar Home Tour website.

 

Volunteers Needed for the Tour of Solar Homes October 6

CRES needs volunteers to help with the Denver Metro-Area Tour of Solar Homes on Saturday, October 6.  If you step forward, you will assist homeowner with visitors.   

There are two shifts: morning from 8:30 a.m. to 12:30 p.m., and afternoon from noon to 4 p.m.  

Volunteers are welcome to spend the half-day they are not working touring homes themselves. Volunteers are also invited to attend a workshop free of charge from 6 – 8 p.m. Thursday, Oct. 4 titled "Solar Photovoltaics and Xcel Energy’s Solar Rewards Program" and presented by Jeff Scott of SolSource and Juliea Gauthier of Xcel Energy.  The
workshops take place at the National Renewable Energy Laboratory (NREL) Visitor’s Center at 15013 Denver West Parkway in Golden, which is two blocks west of the Denver West Marriott at I-70 and Denver West.

Following the workshop, veteran volunteer John Avenson will give a brief orientation for volunteers about the duties the day of the
Tour of Solar Homes
. To volunteer, contact Patty Roberts via email at: patty at pacificmillimeter dot com

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Desperation, but Good Desperation in Local Housing Market

Want to roll a Prius into your mortgage?

The fallout from the subprime mess has come to my neighborhood. This ad appeared in the community paper put out by the developer:

desperation.jpg

Now, you can get a free Prius with the standard solar you get on Harvard Communities’ (massively overpriced) Architect Collection homes. From an economic perspective, it makes a lot of sense for the builder to install solar; it costs them a lot less to do it than people who have to retrofit. But what’s the logic in having the builder fill your garage?

See the solar panels

These developers (especially the high end ones- these’ll set you back $800K) will do anything to avoid having to lower their price. Personally, I think they’re smart, people are more interested in buying things for status than practicality.

The world is crazy, but I shouldn’t complain. It may just get some people out of SUVs and into Hybrids.

But it does bother me that the most important energy efficiency things Harvard Communities is doing are quite cheap (good insulation, sealing the house well, using efficienct appliances) but it’s the splashy expensive stuff like a free car and PV that gets all the press. It makes people think that you have to spend a lot of money to be energy efficient. You don’t, but it’s a belief that is liable to keep coming back to haunt us for a long time.

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National (and Colorado) Tour of Solar Homes, October 6

Note: This post was originally for the 2006 Tour. The 2007 Tour of Solar Homes will be on October 6, 2007. See the original post after the break.

———————Info about 2007 Tour of Solar homes————————

Colorado Solar Tour link
Colorado Tour of Solar Home Flyer
For Southwest Colorado, there’s some info on the SWCRES website.
For Fort Collins area tour, see NCRES Website
For other states, go to the National Solar Tour link

———————Info about 2006 Tour————————
Read the rest of this entry »

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To PV, or not to PV, that is the question.

Are you thinking about installing a photovoltaic (PV) system on your house?  Do you think to yourself, “It will be great to have my meter run backwards and have the electric company pay me for a change”?  “And I’ll be doing something to save our environment.”

The statement above that really bothers me is the part about doing something to save our environment.  My problem with it is the number of resources required: you’re going to have to give something up to buy that PV system, and the thing you are giving up could easily do a whole heck of a lot more good for the environment.  

Suppose you buy a PV system for $20,000 (rebates may halve the price of this, but you’ll see that that won’t make much difference in my argument.)  There’s a lot of argument over the precise numbers, but that system will produce 3,000 kWh (price $9/watt installed, 15% capacity factor) to 4,500 kWh a year ($7 per watt, 18% capacity factor.)   For electricity prices at a balmy Hawaiian $.24 per kWh, that system will then pay for itself (before maintenance) in a minimum of 18.5 years, and generate 83 MWh over that time, or around 150 MWh over the life of the system (30 years.)

Before anyone starts arguing about rising energy prices, let’s compare that PV system to something else we can do with the same money, at the same electricity prices. Suppose we take that same $20,000 and invest it in a 1 year CD at 5%.  After a year, we will get $1,000 in interest, which we will use to buy 500 25watt compact fluorescent light bulbs (in bulk) at $2 each.  We give these away to people who are currently using 100w incandescents.  Over the next several years, those CFLs will save a total of 300,000 kWh (8000h bulb life x 75w per hour saved x 500 bulbs). 

After only a year, we still have $20,000 so we can still buy a PV system if we want to (and take advantage of any rebates we missed out on the year before), we have avoided someone using over 300 MWh of electricity, which is about twice as much as the PV system will generate in its rated 30 year life (and don’t forget the cost of maintenance.)  Plus, most of the energy savings from the CFLs will happen over the next 8 years, rather than the 30 years it will take the PV system to generate half as much.  Most importantly, we have our initial investment of $20,000 back after one year, even though we are giving the CFLs away, while it will take over 18 years to get our money back from the PV system. 

 Because I believe in putting my money where my mouth is, anyone who mails me a receipt for the purchase of CFLs, I will PayPal them up to $5 or $2 per bulb, whichever is less (no more than once per person.)  Household LED bulbs also qualify for the same rebate.  I’ve uploaded a form to fill out, and plan to keep track of the number of bulbs, and the Negawatts generated on my website (as soon as my web guys get to it.)   This will be good for up to $1000 of total payments, or until December 31, 2006 (postmark), whichever comes first.  

Please note: I have withdrawn this offer as of 7/16/07. I have given out about $1,500 worth of rebates for over 750 CFLs, saving approximately 44 kWh per day.

For comparison, a PV system to offset the same amount of power on a daily basis would have to be over 7.5 kW, and would cost about $67,500, or 45 times as much (although it would last about 6 times as long as the CFLs, and it might only cost 20 times as much after rebates.)

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