Looking At A Heating System As A Whole Not Just Pieces

I recently was out on a troubleshooting call to look at a heating system in one of the housing authorities in the Metro Boston Area.  The trouble they were having was excessive cycling of boilers, under heating of some apartments and daily boiler lockouts.  The housing authorities’ efforts to date had been focused solely on the boiler, which seems logical. If you don’t have enough heat it must be the boilers right?

The system’s main components where supplied by seven different manufacturers boilers, pumps, controls, VFD’s etc… add in the different Manufacturers Representatives and Wholesalers and the housing authority was stuck trying to piece together the solution.  As the head of facilities and I began to look at the system as a whole we found the following problems. 

1. The primary or building side of the system was operating at a 50° Delta T, since the heat emitters were all baseboard the units at the end weren’t getting hot enough water.
2. The secondary or boiler side was operating on a 10° Delta T and we were returning hotter water to the boilers than was coming back from the building.
3. In order to compensate for the lack of heat someone had set the BMS control to target 190° in the building loop.
4. The internal safeties kept the boilers from going above 185°, so they were limiting the boilers but the BMS control was sending a 10 VDC signal to the boilers, trying to drive them to 100% modulation.
5. Looking at the boiler cycling the units were banging on and off trying to obtain a target that was out of reach.  As they would be driven to an internal limit shut off, cool down and start again.

The solution we placed the VFD controls in hand and sped up the primary or building side pumps to create a 20° Delta T, this in turn created a 20° Delta T on the secondary or boiler side as our system was now balanced.  The BMS control was set back into a normal outdoor reset mode and began targeting a lower building water temperature.  Since the boilers could reach the target and we were actually taking the heat off the boilers the BMS began ramping down and turning off boilers.  By the time we left the building was being maintained by 1 of the 6 modules.

When I followed up the following week the report was no boiler lockouts and they actually had gotten some complaints about overheating for the first time so they were working with the balancer to find the happy medium in the system.  This case is a good example of what happens to us so many times when we get focused on what seems the logical source of our trouble only to find it somewhere unexpected.

Outdoor Reset v Setback Thermostats

For years the Department of Energy has promoted the programmable setback thermostat as a means of saving energy.  In 2005 several field studies by the Department of Energy determined that in most cases the introduction of a programmable thermostat didn’t conserve energy and in some cases actually increased usage.  The biggest problem they found was that the thermostats either were not programmed correctly or in some cases were not programmed  at all.

Now along comes outdoor reset which adjusts the water temperature based on the outdoor temperature in an attempt to match the heat loss.  When coupled with a programmable thermostat it can be a recipe for customer discomfort.  As the water temperature is reduced the BTU’s into the space are reduced as well since the heat loss is less, the goal is to only put into the space what is leaving.  However if a setback thermostat is in play and not only are we trying to match the heat loss but raise the space temperature 10 degrees it could take a few hours.  To combat this many thermostat manufacturers have added to logic in their thermostat to learn a systems response time and come on a few hours earlier.

If a customer is setting their thermostat back at night to save energy they are better off to just set it and forget it and allow outdoor reset to manage the system.  The long run time to heat the house back up will offset any energy savings.

Or take a look at the next step in the energy saving evolution indoor feedback, with indoor feedback a system can tailor the water temperature to the actual heat loss, synchronize the zones to eliminate short cycling and ramp the water temperature up for those times when it has been setback or turned off.

Article by George Carey about Indoor feedback
Tekmar House Controls

Net Zero Homes more than just reducing utility bills.

A Net Zero Home is defined as a house that produces as much energy from renewable sources as it consumes.  This doesn’t mean a Net Zero Home won’t have an electric bill, they may purchase energy from the grid in the winter and sell it back in the summer but the end tally must be zero.  In 2006 the HERS Index or Home Energy Rating was created with 100 being the standard building and a Net Zero building receiving a rating of 0. A Net Zero home will have higher upfront costs, but lower monthly expenses, since the energy improvements are paid for in the initial building. 

In 2005 the average New England household spent $200.00 per month on utilities; at current interest rates on a 30 year mortgage a person spending $40,000 extra in upfront energy efficiency costs would spend an additional $190.00 per month on their mortgage payments.  So the net might be the same but the real savings is the 129 million BTU’s of energy the average New England home consumes annually, and no that wasn’t a typo.  And this is the real goal of Net Zero building not eliminate energy bills but eliminating off site energy consumption. 

The other part of the equation is making the upgrades not only efficient but economical. New Town Builders, In Colorado has built a model Net Zero home that costs just $26,900 more than their standard home offering.  However,  taking these costs into consideration in the mortgage process has been a challenge since there currently is no mechanism for evaluating the reduced utility bills into a borrower’s ability to afford the loan.  Soon there may be the Sensible Accounting to Value Energy Act would direct federal mortgage agencies to consider the reduction in energy costs in the loan qualification process. 

The SAVE Act is not just for Net Zero Homes,  if passed any energy efficiency improvements will be taken into consideration as long as they reduce the consumer’s utility bills.  The SAVE Act is expected to create 83,000 new jobs by 2020 and save over 1 billion dollars in energy use annually.  Consider a boiler replacement that reduces a home’s energy bill by 30%, in New England that could equate to a $500 per year savings.  And a person looking at a home with a high efficient boiler could qualify for mortgage that is $9,000.00 higher than a home without one. 

Altherma provides a Solution

A recent renovation on the Cape sent the HVAC contractor looking for a solution to a unique set of conditions, provide heating and cooling to a home that sets on the beach, without using a fossil fuel, not be affected by the salt air and fit in to the aesthetics of the house and surrounding area. 

Enter the Daikin Altherma Monobloc this all in one unit will provide heating and cooling with a SEER rating of up to 27 and a COP of 4.  The small footprint of the Altherma and its built in pump allow for an installation over 40' from the house and will be enclosed on 3 sides by a small structure to match the home.  And with Daikin's PE Fin the fins are covered with an acrylic and hydrophilic coat that has efficient corrosion resistance.

More reasons why Daikin is the world leader in Absolute Comfort. 

Energy Consumption in America?

Keeping people comfortable in their homes is what the HVAC industry is all about, when energy was cheap grossly oversized boilers operating at 70% and 8 SEER air conditioning systems with Ozone depleting refrigerants where the norm.  As energy prices increased higher efficiencies and SEER ratings have begun to take over the market.  However, the United States still wastes approximately 58% of its total energy consumption, according to the US Department of Energy.  In 2012 the United States is forecast to consume 99.46 Quadrillion [i]BTU’s of energy at an estimated overall efficiency of 42%.

The answer to energy waste in the US is not that simple since people still want to be comfortable in the homes, have plentiful hot water at the disposal and drive their car to the mall.  A lot has been said about the emerging renewable energy market yet it will produce a little over 2% of all the energy consumed in 2012. 

While we have a long way to go to eliminate the energy wasted in this country there are a few changes we all can make that can have a big impact on saving energy with little or no impact on comfort. 

1. Reduce the thermostat setting on your water heater by 10° to save between 3-5%.   While there is a very slight risk of promoting legionellae bacteria when hot water tanks are maintained at 120 degrees, this level is still considered safe for the majority of the population.[ii]
2. If you have an Indirect Water Heater lower your boiler setpoint by 10° this week if you still have sufficient hot water lower it again.
3. If you have an oil furnace check your nozzle size, many of these units have adjustable firing rates.  When my wife and I lived in Maine we changed the 1.00GPH nozzle for a .65GPH nozzle, the house heated fine the unit was much quieter and we reduced our oil consumption by 20%.
4. When setting up the outdoor reset curve on a hydronic system lower the top and bottom end down 10° below where you normally do and explain the benefits to your customer.
5. If you have a boiler without a reset control that is set to 180° drop the setting to 170°
6. If you haven’t already done so take Masssave up on their offer to audit your house and give you free energy efficient light bulbs, money toward insulating and weather responsive controls.
7. And if you’re a contractor next time you offer a high efficiency heating system don’t forget to offer an Indoor feedback system, which is basically automatic outdoor reset, that Masssave will pay about ½ the cost of the control.

For 2012 lets all find a way to be part of the energy consumption solution in America.

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[i] U.S. Energy Information Administration

[ii] U.S. Department of Energy

BYE BYE Incandescent Light Bulbs

The Lighting Energy Efficiency portion of the Energy Independence and Security Act began phasing in January 1, 2012 this effectively bans the manufacturing and importing of 100 watt incandescent light bulbs.  In 2013 the ban will eliminate the 75 watt with the 60 and 40 watt being eliminated in 2014.  What does this mean to the typical consumer?  They have 4 options; stockpile all the incandescent bulbs you will need, switch to Halogen bulbs, CFL (compact fluorescent light) or LED.  Will this affect your wallet?

Based on the life expectancy, purchase and annual operating cost the 4 options match up like this:

Bulb Type	Unit Cost	Total Cost to own & operate
Incandescent	$0.62	$12.50
Halogen	$1.75	$10.58
CFL	$1.66	$2.95
LED	$19.78	$2.50

Interesting how the LED bulb that cost almost as much as 32 incandescent bulbs will actual cost less to purchase and operate over the course of a year and with a $10.00 a year savings the payback is 2 years. And in terms of payback the CFL is indeed the winner with a 1.25 month payback.

 

How can this help the HVAC industry?  As the consumer becomes more aware of looking in terms of higher upfront costs being offset by energy savings, it should hopefully make the conversation easier when discussing High Efficiency Heating and Cooling equipment. 

Roth Industries new Insulated Floor Panel Systems by Crete-Heat

Simplify your radiant floor installations with the Insulated Floor Panel System.  This system can reduce install time by as much as 2/3 and is available in three different thicknesses for either new construction or retrofit applications.  With the tongue and groove joints there is no taping required.

Are You Underselling Yourself?

The proliferation of the “We Won’t Be Undersold’ mentality has barged its way into the HVAC industry.  Most retail outlets, car dealers now offer some sort of price match guarantee which is great if the 2 items are the same.  Does it really matter where you buy your Sony 42” LCD HDTV 3D TV with surround sound?  Probably not.  But when a consumer uses that mindset when choosing his HVAC contractor you can bet it does. 

When it comes to choosing an HVAC contractor too often it comes down to the piece of equipment being installed, when in reality the choice should be between the contractors first, equipment second.  When dealing with a homeowner make sure that you are selling the features and benefits of your company.

Can you Heat your home in December for $6.15 a day?

You can with an air to water heat pump like the Daikin AC Altherma, at an installation here in New England the Altherma used an average of 45KW per day which at current electric rates works out to $6.15 per day.  And the side benefit is that you will reduce your CO2 emissions by more than 50% over a standard fossil fuel boiler. In the winter an air to water heat pump works by taking thermal energy from the outside and transferring to the inside of the home via radiators, fan coil units or radiant floor heating.  Because the Altherma employs an inverter driven condenser unit it can extract heat from the outside even at subzero temperatures.  And with a Coefficent of Performance as high as 4.54 which means for every 1 KW of energy used 4.54 KW of heating energy is produced or for every $1.00 you spend you get an additional $3.54 free.  And the above $6.15 per day includes the lights and other electric items in your home.

Learn More Here

Is Your System Balanced?

With the shift to small condensing boilers and lots of zones a new challenge has arrived , avoiding excessive boiler cycling.  What is an unbalanced system? In the typical condensing boiler installation it is a situation where the system side is flowing at a lower GPM and BTU rate than the boiler side.  An example is a small zone of baseboard using 2 GPM and 20,000 BTU connected to a 150,000 BTU boiler that can only turndown to 30,000 BTU.  There are several solutions to the problem including ramp delay of a boiler, variable speed boiler pumps, zone synchronization and buffer tanks.  Lee Cook of Capco Supply has put together a great article on using buffer tanks.

 Read Lee's Article Here

TO CONDENSE OR NOT TO CONDENSE

High energy prices have created a consumer driven shift toward high efficiency modulating/condensing boilers. Yet many remain skeptical of the true value of a condensing boiler, especially in high temperature applications, such as baseboard or hydro air. However, the high efficiency boiler creates savings by modulating its firing rate down. For example the Sync boiler, by Lochinvar is equipped with a 10:1 turndown ratio and can fire at a rate as low as 10% of the full rated capacity of the boiler.
Now let’s talk about condensing. In a condensing boiler, when flue gases condense, or change state from a gas to a liquid, latent heat gets absorbed by the water in the heat exchanger. Instead of flue gas heat going up the chimney, its heat is now applied to the system water. The lower the return water temperature, the greater the condensing will be. Since condensing begins at around 135 degrees, designing your system with a 25° delta T and a supply temperature of 160° will yield return water cold enough to condense. With a properly sized boiler there are few days each heating season that require water temperatures over 160 degrees. In fact standard baseboard can still provide heat with water temperatures of 110 degrees.
If that isn't enough to sell it, how about rebates and tax credits of $2,500.00 residentially and, depending on which gas utility, as much as $15,000.00 commercially per boiler.

NO MORE SINGLE WALL TANKS IN PLAINVILLE, MA

With the adoption of 527 CMR Board of Fire Prevention Regulations sections 4.00 and 9.00, Plainville has made double wall oil storage tanks mandatory.  The Board of Health also requires “Interior tanks shall be installed so that any basement flooding will not deteriorate or compromise the integrity of the tank.”  And if you are not familiar with it 527 CMR section 4.03:5(b) States

(b) A supply tank larger than ten gallons (38L) but not larger than 660 gallons (2500 L) shall meet the construction provisions of Standard UL 80, UL 2258 or be a secondary containment type tank meeting the following standards:

1. The primary tank shall meet the German Institute for Construction Technology (DIBt) Standard PA-V1-321, Requirements and Test Methods for Thermoplastic Tanks made from Blow Molded Polyethylene, Rotationally Molded Polyethylene and Anionic Polymerization of Plyamide-6, or an equivalent standard.

2. The secondary containment shall be provided by a liquid tight outer jacket of galvanized steel or stainless steel with a minimum 18 gauge nominal thickness.

3. A means of detecting a leak from the primary tank into the secondary tank shall be provided.

DO YOU NEED A PORSCHE OR A PICKUP

When it comes to replacing a pump you need to know what your conditions are to avoid problems later.  Let’s examine the performance characteristics of 2 Bell & Gossett PL series pumps, the PL-55 and the PL130. Initially many would assume that the PL-130 is a bigger pump and will flow at a higher rate than the PL-55, However that isn’t always true. 

Going back to the Porsche vs. Pickup analogy the Porsche can certainly outrun the Pickup any day of the week right, now hook a 7,000 lb trailer to the back of them and the Porsche doesn’t move and the Pickup runs away.  In this example the PL-130 is the Porsche and the PL-55 is the pickup.  Take a look at the pump curve below:

On the left is the feet of head the pump can operate against and along the bottom is the gallons per minute it will flow.  So at 10 feet of head pressure the PL-130 flows 85GPM while the PL-55 flows 45GPM, but increase the head pressure to 18 feet and the PL-130 drops to 25GPM while the PL-55 now is flowing 40GPM.  Next time your sizing a pump take a minute to consider the conditions it save time and money later on.

ROTH INDUSTRIES LOOKS TO MAKE LEAKING OIL TANKS EXTINCT.

A new marketing promotion “ DINOSAUR IN YOUR BASEMENT” by Roth Industries aims to educate homeowners on the benefits of double wall tanks.  This customizable program allows companies to partner with Roth to create a website that will generate qualified leads for customers in need of tank replacement.  Contact your Roth DWT distributor or FIA for more information.

ARE DEGREE DAYS IMPORTANT

Absolutely, they can really make the difference in calculating your return on investment.  Let’s take a quick look at how this October with the unseasonably warm weather, could impact our perceived savings not only historically but in the future. By using my house as an example, which has a single pipe steam system with a standard efficiency boiler we can see the weather related impact.  Last October we used 82 therms for heating and hot water production, this year that dropped to 50 therms or a reduction in use of 39%.  Since I did not make an efficiency upgrades these savings are strictly weather related.  Now let’s look at my usage factoring in degree days, last October we had 271 degree days vs. 157 days this year.  So my usage last year was .30 therms per degree day and this year .31 therms which is actually an increase.  If next year the weather pattern is the same as 2010 some customers who have made high efficiency upgrades may actually see an increase in the fuel usage, so it is important when discussing energy savings to base it on degree days.