Solar Retrofit - Part 4: High Efficiency Heating & Domestic Hot Water

My previous post regarding the problems with Taylor Munro Energy Systems was very negative.  While the problems with TMES are still not resolved, I'd like to focus this posting on a part of my renovation that worked really well:  The high efficency boiler and the heating system.  

There are three main components to the system: 1) a source of heat: the boiler, 2) something to replace my furnace: a fan coil and 3) a domestic hot water (DHW) tank that runs off the boiler.  In addition, I've done a retrofit of radiant floor heating.  This step is optional and was done to allow zone heating of different areas of the house.

The Boiler
Hot water to run the fan coil, radiant floor heating and the DHW tank is supplied by a high efficiency condensing boiler made a Canadian company: IBC Technologies from British Columbia (http://www.ibcboiler.com/).  The model I selected was the VFC 15-150.  This unit is a modulating boiler that can vary its output from 15,000 BTU/hour to 150,000 BTU/hour (hence the 15-150).  The boiler can be configured to support up to three different heat loads - in my house they are: Forced Air heat, domestic hot water (DHW) and the basement radiant floor heating.  The boiler comes with a themostat which is mounted on the outside of the house and it uses this to adjust the temperature of the water that it supplies to the fan coil and the radiant floor heating - the colder it is outside, the hotter the temperature of the water.  When running, the exhaust gases are cool enough to vent through a side wall using specialized plastic piping.

The different heat loads are assigned different priorities with DHW having the highest priority.  This is because you'd notice a temperature change of a couple of degrees in the shower but probably wouldn't notice if the air coming from the furnace vent varied by a few degrees.  As the boiler provides heat to a load, that loads priority slowly drops until the other loads have a chance to get heat as well.  

In addition to the 15-150, there is a larger 45-225 unit.  If you need even more than 225,000 BTU's per hour, multiple units can be connected together.  Instead of simply connecting the boilers in series, the controllers in each boiler talk to each other so that only the units required to provide the given amount of heat actually required fire up.  The north Edmonton location of Cronkhite Supply has a setup of three boilers - informally, I've heard 10 of these units can be connected together, enough to heat a good sized apartment building.

I have to say that I am very impressed with the unit.  The boiler programming is set up minimize the outlet temperature of the water it heats since the lower the temperature, the greater the efficiency.  In addition to all this, IBC is planning on enhancing the logic within the boiler to control solar collectors so that the boiler will fire even less.  

The Fan Coil
A fan coil is the unit which replaces the furnace.  The unit I selected is made by a Canadian company: Energy Savings Products (ESP) here in Edmonton (http://www.hi-velocity.com).  I ended up selecting their low-velocity "LV-120" unit rather than their hi-velocity unit as I was tying in to the existing (low velocity) duct work.  The unit will produce over 120,000 BTU's per hour of hot air from an inlet water temperature of 190 degrees F.  This is actually more than I need but I selected this unit with the expectation that I would run with a lower inlet water temperature - again, the lower the temperature produced by the boiler the more energy is extracted from the burning of the natural gas.

The Water heater
Hydronic systems use "indirect" water heaters where the heat from hot water output by the boiler is transferred to the potable water for household use.  The efficiency of the heat transfer between the boiler water to the potable water is a function of the shared surface area between the two.  In most indirect water heaters, the output of the boler runs through a coil of copper pipe in the middle of the tank.  Instead, I selected a Triangle Tube tank from the Triangle Tube company of Blackwood NJ (http://www.triangletube.com).  In these tanks, the walls of the tank itself is made of of a flattened tube.  The result is that almost the entire surface of the tank is used to transfer the heat from the boiler water to the domestic hot water.

I'm sure that anyone who follows this site is familiar with the 100 mile diet.  While sourcing most of my components exceeded 100 miles, I was nonetheless surprised by how many components of my HVAC system were made in western Canada.  The boiler is an impressive piece of equipment and comes from BC, the fancoil is made right here in Edmonton, the copper header that the hydronic pumps connect to is made in Wetaskiwin and I installed some automatic duct dampers that are made in Camrose.  So far I've been very impressed with all the components I've discussed in this posting and I'd heartily recommend them.

 

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I would like to view all parts of the sloar retrofit, where can i do this?

Unfortunately there's not much more to see at this time.  I had some problems with the original shipment of the collectors not being properly packaged for shipment (see part 2 of my blog: http://greenedmonton.ca/node/289) and it took Taylor Munro Energy Systems 9 months to get me a replacement collector.  Right now the collectors are sitting on the ground waiting for warmer weather.

If I ever get this project complete (and my wife agrees), perhaps I'll see about putting my house on the eco solar tour.
 

I'm building a new home west of Olds Alberta and will be doing most of the work myself. I am putting in floor heat in both the basement and main floor, I plan to have some solar to boost the temp. In Alberta what does the code say about DHW and infloor heat? Can I run DHW from the same system that supplies the floor heat (open system) or do the two systems have to be seperate?

I'm sorry but I don't know exactly what is allowed by code and what is not.  In my system, the boilers heats what I'll call a Heat Transfer Fluid (HTF) which is circulated through either the fan coil, radiant floor heat pipes or the heating coils of the water tank.  The HTF is totally seperate from the potable water. 

In my installation, the HTF actually is plain water so I don't see any reason why you couldn't use domestic water.  In fact, after I made the bulk of my HVAC purchases I ran across this article where a guy in Edmonton used a on-demand water heater to run a fan coil from the same manufacturer I used: Energy Savings Products.

 

We have two flat roof apartment buildings in Edmonton, 12 suiter & 20 suiter, both buildings appr 35 years old. Would like to look into using solar panels to provide energy to lower heating and boiler costs. Any idea who to approach on this? Thx.

I'd been reading about solar energy for years before I started my project and I thought the industry was much more mature than it actually is.  Despite the fact that Edmonton will shortly have two net-zero home, the industry is very young and there are very few people who really know what they're doing and have solid experience.

Since it appears you are looking for a solar thermal system - along the lines of what I'm doing - I'd recommend that you contact Andy Smith at Solnorth Engineering (www.solnorth.ca).  Andy is a professional engineer who has helped me out with a few different aspects of my installation.

My second choice would be to go to Cronkhite Supply in north Edmonton: 12224 152 St.  They have started carrying Viessmann solar collectors (www.viessmann.ca) which wasn't an option when I started my project.  Cronkhite was bought out by Wolseley last year so I'm not sure which web site you should be checking: www.cronkhiteexpress.com or www.wolseleyexpress.com.

Thirdly, there are a couple of guys I've met with who just started their own solar energy business who seem promising - in fact I was planning on using them to commission my installation:  Gary and Ron from Terra Solar (www.terrasolar.ca).

If you are really looking for a solar electric (photo voltaic) system, then you should contact Gordon Howell at Howell-Mayhew Engineering (www.hme.ca).

A name I heard a lot when I started my project was Harold Verburg at Trimline Design  (www.trimlinedesigncentre.com).  Unfortunately, it always seemed that they either didn't have what I was looking for or, by the time they got a particular item, I had managed to source it from somewhere else.  The Trimline business in Edmonton is closed and the web site says that it's being run out of Harolds acerage in Millet but my calls and e-mails over the past few weeks have gone unanswered.  I know that Harold is highly regarded in the solar community in Edmonton but based on the lack of customer service I experienced, I can't recommend them.

If you've read through the Green Edmonton web site, you'll be familiar with my problems with Taylor Munro Energy Systems out of BC (www.taylormunro.com).  While the company has reorganized, I would highly recommend you NOT go with an out of town vendor.  Doing so is just asking for trouble as any problem will be amplified ten-fold by the time and distance.

When I started my entire project, I was very interested in evacuated tube collectors because of their ability to produce significant amounts of heat due even in very cold temperatures.  Zev & Patrick at Thermomax Industries (www.solarthermal.com) are great.  Unfortunately, the local rep is Zig from Home Pure Water & Solar (www.homepuresolar.com) and he's a jerk.  When I asked about how much a single family home domestic hot water system might cost he said "It's more than you expect - be prepared to spend a lot".  Okaaaay.  When I asked if he had a general schematic of the components of a DHW system, Zig said he could put one together for $500.  Not an engineering diagram, not a detailed design, just a generic list.  When I asked for an estimate on how much of my water heating would be offset by the solar he suggested that we hire a professional engineering firm "for a few thousand dollars" to do the calculations.  My recommendation: avoid at all costs.

Finally, this is clearly not an exhaustive list of all the solar businesses in and around Edmonton.  To get more than just my opinion/experience, I'd recommend you contact the Canadian Solar Industries Association (CanSIA) at www.cansia.ca.  They were incredibly helpful when I was having my problems with Taylor Munro.

Whew, big posting.  I hope that helps.

 

Re flat-plate vs evacuated tube collectors.

www.solar-rating.org/ratings/OG100DIRECTORIES/OG100DIRFULL.pdf
I was surprised to see that the best performing flat plate collector (Enerworks commercial collector) performs better up to 50C deltaT than all the evacuated tube collectors of equivalent size.

Great posting! Thanks for all of your information.
I know Harold Verburg and you couldn't find a more knowledgable guy. The solar society is also a great resource, talk to Rob Harlan.
I am with a new solar company called Eco Thermal Systems. Our roots are in geo thermal drilling (www.ecothermaldrilling.com). We found that we wanted to offer a full range of alternative energy products so here we go. Just got back from New york, checking out the whole LED scene, very exciting stuff.
We are reps for WSE out of Saskatoon and we cover Edmonton, Calgary and Grand Prairie. I would love to put together a quote for anyone who wants to check out their solar options, FOR FREE. So far I have found the clients I have been working with are willing to work with us to come up with a plan, great stuff!
The team at WSE help design the system and have alot of experience. check out their website. Very focused on Canadian weather and what works and what doesn't in our climate.
We can back the price and we have the product for all of your solar needs.
Good luck everyone!
Melanie
melanie@ecothermalsystems.com

on climate and temperature variations need to pay special attention.

I'm interested to find out how your solar will be integrated into the boiler loop, will you plumb in parallel and use it to directly offset the boiler or is it only going to be used to offset DHW production? I'd also like some info with regards to if you are using the boiler controls to modulate the LV unit fan, similar to how IBC uses their own air handler. What was the reason for chosing the LV over the IBC unit?

Thanks in advance

Dave

Initially the solar will be pre-heating the DHW while I wait for IBC to develop a module that will control the solar and tie it in to the boiler.  Once that module is in place the solar will become the primary source of heat and the boiler will the the backup heat.  This builds on the ability of the boilers to be chained together.  I've attached a couple of schematics here for your reference: TM Schematic 1.pdf and TM Schematic 2.pdf.

Regarding the fan coil and the boiler:  The house thermostat is connected to the fan coil.  There's a "dry contact" (i.e. unpowered) in the fan coil that the boiler is connected to.  When the thermostat calls for heat, the contact closes and starts the boiler.  The boiler itself senses the inlet and outlet temperature and, in conjunction with the temperature sensor outside the house, modulates it's output appropriately.

When I started my project I talked to the guys from Cronkhite Supply (south side store - now closed) and got a quote for the IBC boiler, triangle tube tank, ESP fan coil and all the associated fittings. Later when I started working with Taylor Munro, they recommended the IBC boiler and since the other equipment on the quote checked out, I just went with what Cronkhite carried.  I don't know anything about the IBC fan coil so I can't say how good it is or how much of a hassle it is to buy.

I hope that helps.

Ken

 

Very helpful.. thank you
sean c

Since reading this article I decided to equip my home with a similar system, however I'm using two ESP LV-E 1050 coils and a Triangle tube PE-110 combi boiler. My question to you is using your outdoor reset what temps are you feeding the fan coil and what are your air discharge temps like. I would like to max out on the coldest day on my system at about 140-150 deg F, but on milder days I would like a cooler temp but still have effective air discharge temps.

Thanks again

I'm sorry but I can't answer your question as I've never measures the discharge temperature of the fan coil.  The initial configuration by the plumber had the boiler reach it's max temperature of 70 C (158 F) when the outside temperature was -30 C or colder.  I've since adjusted the boiler down to a max of 60 C (140 F).  Then, to compensate for how long it would take to heat the house, I've programmed the main floor radiant floor heating and the fan coil to come on the the same time (I have two programmable thermostats in the main floor hallway: one for RFH and one for fan coil).  The fan coil is set to 20 C and the RFH to 19C - I set the RFH lower so the house doesn't overshoot the desired temperature. 

The reason for dropping the boiler temperature was to maximize the amount of time that the solar would be able to contribute.  Saturday (October 30, 2010) was a bright sunny day in Edmonton and even though the temperature outside only reached 11 degrees C, my storage tank hit 61 degrees C (even after three people had showers).  Sunday morning the tank was down to 57 C (after a load of dishes and a load of laundry Saturday evening).  When we got up on Sunday, the outside temperature was right around freezing which had the boiler running at 51 C to feed the fan coil.  With the solar feeding the boiler loop the actual temperature of the heat transfer fluid was almost 57 C which had the boiler ran at its lowest possible setting: 15,000 BTU/hour.  It is possible for the solar to heat the boiler loop to the point that the boiler doesn't burn any gas.  On the IBC boiler it appears this happens when the actual temperature of the heat transfer fluid is more than 11 degrees C hotter than what the boiler figures its target temperature should be.  This means that on Sunday morning with the boiler having a target of 51 C for the fancoil, the solar tank would have to provide 62 C (or more) to keep the boiler from firing.  Even though the boiler is still running, the solar is definitely helping.  Based on what I saw this time last year, I'd estimate that the boiler would have ad to run arounf 35,000 to 40,000 BTU/hr to run the fan coil.  Once I've got a few months of numbers I'll write up a posting showing my results.

Ken

Hello Ken. Just discovered your blog and thought someone out there might have suggestions for me. My house has been a work in progress that I began in 2004. In 2006 I had radiant in-floor heating roughed in before pouring the basement. The following year I was ready for my boiler system, but the person who installed the in-floor loops was not available to do the work. Another mechanical "expert "was highly recommended to me so I contacted him. He installed my boiler system: Munchkin high efficiency modulating boiler, Superstor Ultra indirect fired hot water heater, HPV Boiler and floor management systems, and a fan coil (blower). Problem is, the installer was very arrogant, unpleasant, and difficult to get information out of, so I learned very little about how to manage the system after it was installed. I now need to have someone come out and check on my system because there are a couple of things that aren't quite right and I absolutely refuse to subject myself again to the attitude of that installer. Any recommendations out there for me? I am looking for someone who really understand these systems. Thanks. Sheryl

Sheryl,

Are you in Edmonton? If so, I would recommend calling Bob Patno

http://patnosplumbingheatingandac.com/

My father has a gas boiler for baseboard hydronic heating and DHW. He was having trouble with it and somehow got Bob's name (possibly from the boiler manufacturer). I was impressed with his knowledge and honesty.

B.

Sheryl,

I hired Brent Massel for my installation and he was FANTASTIC!  I actually had him back last fall (fall 2011) to make some wiring changes that allow the boiler to provide heat to the fan coil and the water heater at the same time.  He has experience with solar collectors (both flat plate (my system) and evacuated tube) and geothermal systems.  He returns calls promptly but he keeps himself pretty busy so you may have to wait a bit before he can get out to your place. 

His contact information is:

Brent Massel

theplumberman _at_ gmail.com

780-964-6392

Ken

 

There you go, Sheryl. It's always nice to have options. If, for whatever reason, you prefer to deal with company rather than an individual plumber, I had a good experience with Harmcor Plumbing about 10 years ago when the gas valve failed on my furnace.

 Good luck,

 B.

I just had a IBC sl20_115 installed in my two story attached garage. I live in Kamloops. The guy who fired up the boiler fired it up and left. He said there was an issue that only IBC could resolve and he would phone me back and come back to the house. Well no call yet and the thermostat will not control the boiler only to manually shut it down. I have only one zone at this time which is 1000 sq. feet of slab. the slab warmed up to about 65 degrees f. and it is wonderful. Why would the thermo stat do this.?
Thank you, Clint

Hello Clint,

I'm sorry but I  don't understand the comment "the thermostat will not control the boiler only to manually shut it down".  Let me explain how my system works, maybe it will shed some light on your installation. I have defined the space heating load as "Reset Heating" using the control panel on the boiler.  There are various configuration parameters but the important ones are (if memory serves):

  • the Design Outdoor Temperature – the coldest expected weather typically experienced at the installation site;
  • the Design Supply Temperature – the desired boiler operating level to occur at that coldest day

The colder it is outside (as determined by the dedicated temperature sensor connected directly to the boiler), the hotter the boiler runs to compensate for the additional heat loss.  When I turn up the thermostat, it sends a simple ON command to the boiler.  It doesn't matter if I turn up the thermostat by 1 degree or 20 degrees - it behaves just like a light switch to turn on the boiler and associated pumps.  Once the boiler is running, it uses the outdoor temperature sensor to calculate the target temperature of the water coming out of the boiler.  The boiler then uses temperature sensors to check the temperature of the water entering and leaving the boiler to calculate how much gas to burn to meet the target temperature.

Having said all that, the comment "the thermostat will not control the boiler only to manually shut it down" sounds like it is behaving exactly the way it should.  Can you explain what other behaviour you were expecting?

Ken

Noticed this thread. I am presently taking the renewable energy internet course at Vermillion through lakeland College and i have done 2 small windmill installs, a solar panel and array installation and one evacuated tube installation. I am presently in the middle of the solar class and i eventually want to get a NABCEP for PV and solar heating certificates. I would like to work with some companies in the Edmonton area doing installs whether PV or solar heaters ( be they flat plate or evacuated tubes) and whether they are off grid or on grid. I would even work a couple of days for free just to get some more experience. If anyone can point me in the right way it would be much appreciated.

Craig, give us a call at (780) 566-6058. I am interested meeting with you.

Mikhail Ivanchikov
Dandelion Renewables

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