Cool ideas?

Sometimes I get these seemingly insane ideas, only to find out later that they were somewhat rational. The subject matter of those ideas is typically not my strong suit. That’s why I tend to be infuriatingly quick to dismiss them.

Air conditioning is on my list of subjects that are not my strong suit. I grew up in Germany, where air conditioning is virtually non-existent. I ran into active cooling for the first time while visiting the Caribbean, and again years later when I moved to Chicago.

I regard summer air conditioning in the Midwest as a necessary evil and have a pronounced dislike for the temperature extremes we have to tolerate between the outdoors and conditioned indoors. I dread stepping into a grocery store or office building that feels like an ice box.

Since we started our deep energy retrofit, I’ve had to wrestle with the question on how we will keep cool during the dog days of summer without creating an ice box. I quickly learned that “cool” is somewhat secondary. The primary problem to tackle is how to keep the relative humidity at a comfortable level, i.e. under 60% (preferably at 50%).

We already have an Energy Recovery Ventilator (ERV) that supplies fresh air into the house, yet keeps the outside heat and mugginess at bay. My seemingly insane idea was to install an air-to-water heat exchanger in the fresh air supply duct to remove humidity through condensation, and deliver pleasantly dry air into the house through the ERV duct system.

Simply put, I wanted to run the muggy outside air across a cold air conditioning coil to dry it out. But I was told that there was no such air conditioning device that could be combined with an ERV. Yet, I clearly wasn’t alone with this idea.

Just in the past couple of years I started reading about ‘Magic Boxes’ that basically combine the function of an ERV, or HRV (Heat Recovery Ventilator), with that of a small air-to-air heat pump, i.e. a small air conditioner.



Unlike our ERV, which uses and enthalpy wheel as a heat exchanger, a Magic Box uses an integrated air-source heat pump to transfer thermal energy between air streams. But they also can provide some additional limited conditioning – additional cooling (and drying) as well as heating.

One company (Build Equinox), located two and a half hours south of us, brought the CERV (Conditioning Energy Recovery Ventilator) to market just a few years ago. The CERV has an advertised heating capacity of 3,850 Btu/h, and cooling capacity of 2,400 Btu/h. These numbers vary depending on outdoor temperatures. One article listed a price of $4,500 for the CERV.

A competing product is the Boreal 12000 by Minotair out of Quebec, Canada. This Magic Box is more compact than the CERV and, in heat pump mode, has a listed heating and cooling capacity of 9,400 Btu/h and 8,700 Btu/h respectively. I read one article that pointed to a price of around $3,200 for the Boreal 12000.

Either the CERV or Boreal 12000 could be used instead of an ERV or HRV.

Going back to my original idea, combining an air-to-water heat exchanger with our existing ERV, I came across what looked like a promising option. An article on described a variety of air-to-water heat pumps that could provide chilled water to the air-to-water heat exchanger.

In this function, the air-to-water heat pump would basically function as a chiller. But it could also reverse its cycle and produce hot water for domestic hot water consumption or a hydronic heating system.

The challenge would be to find a right sized unit that I could combine with our ERV, and that would be affordable. If you thought the CERV or Boreal 12000 were expensive, prepare yourself for a sticker shock while shopping for air-to-water heat pumps.

Nevertheless, I feel vindicated that my idea wasn’t that insane after all. But it has only brought me somewhat closer to a solution that would provide cooling and a comfortably low relative humidity during the dog days of summer in our deep energy retrofit.

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Un-freaking believable!

This is not a proud episode, because I unintentionally exercised cruel and unusual punishment.

Last fall, one of my clients let me salvage a small hickory from their yard that otherwise would have been cut down. But the salvaging quickly turned into butchering.

I am not sure if there is a word for upside-down decapitating. If there is, that is what I did to the hickory: I cut off its vital two inch tap root in the transplanting process. Not only that, but I also hauled it for 40 miles in the back of my truck during that warm and dry fall day.


Back at my house, what was left of any leaves looked like dried tobacco and crumbled upon touch. I still planted the poor fellow, yet had no expectation that it would survive.

And that seemed to be its fate. By late May, everything around us had leafed out, except that dry stick in our park way, which once was a proud hickory. Even my neighbors noted and inquired if I would remove it.

Before going down that route, I cut off the very tip of a lower branch – and detected some green cambium behind the bark. Was it really there or was it something that I wanted to be there? In any case, it was a good excuse to delay the removal for a little longer.

By mid June, I got confirmation that the green cambium wasn’t wishful seeing on my part. This resilient son of a bitch developed buds, which kept growing and eventually exploded into leaves.

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Un-freaking believable!

I should also disclose that I poured a five gallon pail of water at the tree base pretty much every day since late April. And thanks to my new rain barrel, I continue to do so.

Yet, this is still a very tenuous situation!

While we had days with dry and hot wind in late June, some of the leaves started to dry up again. I kept watering and it looks like I was able to stop that trend.

Have no doubt. This fellow will take a few years to recover from my butchering. I am just glad I didn’t kill it after all – yet.

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Front porch planters

I felt adventurous: Having the rain barrel set up made my watering chore a lot easier. So easy, in fact, that I decided I could handle a couple more planters.

While I turned the back porch planters into a salad bar, the front porch was asking for something slightly more ornamental.


But before I got to the growing part, I had to prepare a spot that would hold planters.

At some point, the previous owners poured a crude concrete cap with a round top over the graystone wing walls that frame the staircase to the left and right.


This is a perfect location for planters, but I first had to cut and grind the round concrete top into a flat surface and mount a pressure treated board on it.

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The board bought me some extra width and served as the base for the next step: Extending the architrave profile from the column bases all the way across the wing wall. I had purchased some cedar boards that I milled and assembled into a matching profile. I chose cedar in the hope that it will age and turn a similar gray color to the limestone.


Mirroring the existing profile required a fair bit of planing to match up all lines. Thanks to our friend Job, I had become a proud owner of a handful of quality planes, and knew how to keep the sharp. And let me tell you, a good tool is half the battle!

I was doing the milling and planing close by, in front of the house, and always had a few kids stop by wondering what I was doing. But once I whipped out the plane, I had a real audience with jaws wide open. This was something the kids had not seen before.

I asked them to pick us some of the shavings and smell it – smell the cedar. That caused a real sensation. I think every single kid took some shavings home with them. I put the rest in containers and placed it in our closets.


To make sure the planters don’t get blown or knocked over, I assembled two boxes (also cedar) that would hold them in place.

All that was missing were the actual plants. I opted for Nasturtium.

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These are very ornamental, yet edible. We love that nutty, yet spicy taste of pragmatism!


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Rain barrel hook up

Well, it’s less of a rain barrel and more of a rain tote – a 250 gallon IBC tote! (IBC: intermediate bulk container). Considering that I have 1,500 square feet of contributing roof surface, I didn’t want to tinker around with 55 gallon rain barrel drums.


An IBC tote comes with very convenient plumbing connections. For example, the screw lid on the top comes with a standard two inch threaded female connection. All I had to do is connect the supply pipe to it with a two inch male schedule 40 connector – and, done!


The tote also comes with what you may call a faucet. A ball valve drain with a spout, and it is even located at the very bottom. Filling up a watering can from a regular faucet eats into your time. But this thing has a flow rate that fills a two gallon watering can in less than ten seconds. I love it.

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The only thing that it didn’t have was a plumbing connection for an overflow. I solved that problem with a two inch bulkhead fitting. Because – remember – the supply pipe to a rain barrel should be the same size as the overflow. Two inch supply, two inch overflow.


To fit the two inch bulkhead fitting, I had to drill a three inch hole into a piece of vertical and flat tank wall. That got me below the maximum fill line of the tank. But a couple of elbows got me back to that 250 gallon fill line.


I also included a piece of mosquito screen across the overflow pipe. This way I keep the blood suckers from breeding in my barrel. On the supply side, the screen in the diverter-filter combo keeps the critters out.

Oh yes–and I had to connect the diverter to the rain barrel (or tote) with a couple of elbows and some two inch pipe.


Now, where did I find this beauty – this IBC tote? Craigslist! It came from an industrial cookie bakery and had originally high fructose corn syrup in it. Cost: $75. Sweet, isn’t it?

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Downspout diverter set up

Fitting my new, homemade diverter-filter combo into our downspout was my next task. Its was fairly straight forward stuff.

I cut out a piece from the existing downspout to fit in the diverter. The piece I removed was slightly shorter than the diverter is tall to assure it slides into the downspout.


The diverter-filter combo is fairly heavy. I needed two sturdy angle brackets on the porch post that would hold the diverter. I also installed two saddles that would keep the diverter in position for a perfect connection to the downspouts.

Well, an almost perfect connection … My five inch downspout is still a little smaller than the six inch diverter. To overcome the one inch discrepancy, I flared the end of the downspout that connects to the top of the diverter.

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Once the diverter was sitting on the brackets and pushed into the saddles, it fit like a glove. Last but not least, I strapped it to the porch post.


What isn’t included in this set up is a winter bypass. At the beginning of December, I will have to disconnect and take down the diverter-filter combo and replace it with a piece of downspout for the duration of the freezing months. This way, I will bypass the rain barrel altogether for that time.

Oh, yes! There is a rain barrel involved, isn’t there?

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