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Intertek Testing Services NA, Inc. 8431 Murphy Drive, Middleton, WI 53652 14 December 2011

Dr. Tom Butcher Brookhaven National Laboratory Upton, NY 11973

RE: NYSERDA Report No. 11-17 “Review of EPA Method 28 Outdoor Wood Hydronic Heater Test Results”

Dear Dr. Butcher:

As you know Intertek was one of the labs that conducted tests that were the subject to the NYSERDA report. As this report makes many statements and assertions that appear very critical of laboratories involved in regard to competence and quality of the testing, we find it potentially very damaging to Intertek’s reputation. Whether or not it was intended, this report is being regarded as an attack on the com petence and credibility of independent laboratories generally. We have, therefore, reviewed the report in detail and are submitting the attached response.

Aside from the specific comments in our review, our main c oncern is that the report implies that the i ssues raised are equally applicable to all laboratories involved. We strongly feel that this is inappropriate. We believe that all tests and reports submitted by Intertek under the EPA OWHH partnership program procedures were in compliance with t he requirements and represent the highest level of quality.

There is, of course, no doubt that the EPA M28 OWHH procedures themselves

were deficient which did result in laborat ories being required to report results of less accuracy than was assu med. However, Intertek consistently brought these issues to EPA’s attention and implemented procedures to improve the accuracy of

our results.Intertek Testing Services NA, Inc. 8431 Murphy Drive, Middleton, WI 53562 It should also be pointed out that the susp ect test results (high efficiencies) that led to this process were not only issued by the lab, but were accepted by the manufacturers and reviewed and accepted by EPA apparently without any recognition of what should hav e been an obvious problem.

Please accept our comments as a technical review and critique of the report itself.

Sincerely,

Rick Curkeet, PE Chief Engineer – Hearth Products

cc: Amanda Aldridge - EPA

Gil Wood - EPA

Lisa Rector – NESCAUM
Louis Fontaine – Maine, DEP Phil Etter – Vermont, DEC Marc Cohen – Massachusetts, DEP Randy Orr and John Barnes – NYSDEC

Robert Lebens - WESTARPage 1 of 10 Intertek Review of NYSERDA Report No. 11-17 “Review of EPA Method 28 Outdoor Wood Hydronic Heater Test Results”, September 2011

12/14/2011

The subject report is described as a review of the 23 test reports submitted for the wood fired hydronic heaters qualified by EPA under phase II of the Voluntary Hydronic Heater Program. Intertek has re viewed this report and has the following

comments.

It should be understood that the test method – EPA Method 28 OWHH – was not a consensus standard. It was taken, nearly verbatim, from draft 4 of a test method that was under development by ASTM Subcommittee E06.54 in early 2006. The eventual ASTM standard (E2618) that wa s published was based on draft 12 of this procedure. There were, thus, many defi ciencies in the EPA method. The method was also essentially new and had not been applied or validated to any significant extent before it was implemented. It was largely the demands of NESCAUM and North East States air quality regulators – th e same interest group that sponsored the
NYSERDA Review - that demanded EPA esta blish the program quickly and without any attempt to validate the te st method. It should thus not be surprising that some results of questionable accuracy have been produced.

Since the authors have not included the actual data in the report, it is impossible to verify their statements. It is our understanding that the laboratories provided all the
data and the details of all calculations. NYSERDA has not provided in this report any means for us to check of verify their assertions. However, as Intertek tested 11 of the appliances involved we do have detailed and complete knowledge of this portion of the data set. We have reviewed this data in detail and stand behind it 100%. That is not to say that we do not re cognize that some of the results have a large inherent error. In fact, Intertek objected to the requirement for measuring heat output on the supply-side of the system because we had determined that the error was too large for a reliable measurement.

The primary issue that led to this review was the issuance of reports and subsequent publication on EPA’s “Burn Wise” web site listing of qualified hydronic heaters which showed heating efficiencies highe r than is theoretically possible for appliances that do not incorporate latent heat recovery through water
condensation. It has been demonstrated th at this theoretical upper limit is about 85% based on the Higher Heating Value of th e fuel. However, at least 6 products were listed with efficiencies reported at 88% to 99%. We note here that none of these reports was issued by Intertek.

The NYSERDA report fails to postulate or identify a specific cause for the erroneous results. Instead, it appare ntly assumes that all tests were conducted in compliance
with the test method and thus focuses on potential for error within the narrow confines of testing in compliance with the method. While we do agree with aPage 2 of 10 number of the recommendations in this re port - in fact many originated as our
recommendations as far back as the initial method development – none appear to be sufficient to explain the very hi gh efficiency results at issue.

In addition, we find many of the statemen ts and assertions in this report to be unsupported by the facts. The fo llowing are just a few examples.

1) The report states that 14 of the 23 units reported higher efficiencies than determined by the stack loss method. But 11 of the 23 were tested by Intertek and in only 2 of the 44 individual test runs in volved did we see delivered efficiencies based on the load-side measurements that were slightly higher than the B415.1
calculated stack loss efficiencies. None of the Intertek weighted average or 8-hour efficiencies where higher. In the two individual test r uns where there was an issue with this, error in the B415.1 stack loss va lues could easily explain the difference. The accuracy of stack loss methods is unknow n and the approach is least reliable for appliances that cycle frequently in com bustion air supply and burn rate. In both cases the delivered efficiencies we reported where under 76% well under the theoretical upper bound for non-condensing appliances. Apparently, however, NYSERDA used their own stack loss calculation procedure, which appears very crude. Not using the CSA B415.l procedur e is hard to understand, as it is a published, consensus-based method. They did not provide any estimate of the uncertainty of their approach, but it is surely large enough to put any conclusions about the delivered efficiency into doubt where the difference is less than 5 to
10%. Our estimate of the uncertain ty in the CSA B415.1-2010 method around +/- 3%. The method used by NYSERDA (BNL Calculation Procedure) is based only on average CO 2 concentration and average stack temp erature and must certainly have a much larger uncertainty. The NYSERDA re port states that the method used is "reasonably accurate under steady-state conditions". That may be true (although no data are provided to support this posit ion), but these appliances never operate under steady-state conditions even in category IV test. Burn rate , fuel composition, heat release rate, flue gas temperatur es, and flue gas composition change continuously. Many of these units cycle at least a few times even at the high output

rate.

Based on the efficiency values originally published on the EPA Burn Wise website, we believe 6 appliances were listed with efficiencies that are theoretically impossible, and 2 more with efficiencies that should be considered suspect. Thus,
15 of the 23 models listed had effici ency values that were plausible.

2) The report does not recognize that the test method includes a bias toward higher than actual delivered efficiency results. This is due to the requirement in the method that during the pre-burn cycle the coal bed is to be "fully charcoalized". This is easy to accomplish by burning wood with small cross sections for the preburn. However, at the end of a test run the actual test fuel load is often not "fully
charcoalized". The fuel that remains at th e end of a test run can have significantly lower energy content (for the same weight) than the coal bed that is present at thePage 3 of 10 start of the test. Thus, the heat content of the fuel ac tually burned during a run can be significantly higher than the input calc ulated. This tends to bias the efficiency upwards by as much as 5 to 7 percentage points by our estimates. The stack loss
method does not have this bias to the same degree. It measures the losses up the chimney and subtracts them from the calcul ated input. Therefore, the actual input being different than the assumed input has a smaller impact on the results.

The report also fails to note that at least 3 of the high efficiency results are for pellet burning appliances where the fuel i nput, moisture content and coal bed
charcoalization should not be factors. A pellet appliance test that results in unrealistically high efficiency indicate s a significant error in the output measurement, an error in the determination of the heating value of the pellets or an
error in the measurement of the fuel mass consumed or a combin ation of these.

3) The paper makes many recommendati ons which are not supported by any evidence or analysis. For example, it recommends a 15 second reading interval even though the revised EPA Method WHH already requires 1 minute intervals – 10 times
more often that wa s required by the original me thod. They provide no supporting evidence other than stating that "a ten minute period may not adequately represent peaks and valleys of the cycle”. Our analysis of 1 minute data processed at 2, 5 and 10 minute intervals shows very little differe nce in any of the key outputs of the calculations. Peaks and valleys certainly are evident in the supply-side outlet and return water temperatures and flue gas composition data, but the key measurements for determining heat output on the load-side and the particulate emissions are typically very steady. This is because the load-side heat draw is maintained as close as possible to the ta rget output rate. The water temperature and flow rate provided to the heat e xchanger is thus nearly constant and temperature exiting the heat exchanger is therefore also fairly constant. The dilution tunnel flow and particulate sa mpling rates are maintained at nearly constant levels as required by the A STM E2515 method. Therefore, the key measurements – heat output and total particu lates – rely on data that is not subject to substantial “peaks and valleys” during the test runs and higher reading frequency adds no significant precision.

4) Intertek knew from the sta rt that the supply-side meas urements had a substantial accuracy problem and advocated the load-s ide measurements fro m the beginning. The ASTM E2618 method has always required this . In fact, in some of our tests we
saw clear issues with the accuracy of the supply-side measurements and obtained agreement from EPA staff that we should report the load-s ide results. This might account for some of the "incomplete" da ta as we did not include the erroneous data for affected test programs.

In addition a detailed measurement uncertainty analysis conducted by Intertek demonstrated that the uncertainty of supply- side measurements could be as high asPage 4 of 10 ± 22% for low output tests even if all meas urements met the specified accuracy and are more likely 2 to 3 times larger under the actual test conditions.

5) The simplest conclusion one could draw fro m a review of all the data is that the most obviously erroneous results all originat ed from a single source. This is a fact that is entirely absent from discussion in the report. An objective review of the data could not fail to uncover this reality. Th e paper also fails to postulate a probable cause for the largest deviations - i.e. 85 to 99%+ efficiencies. C ould it not be that the raw data was simply wrong? Where any of the suspect results related to appliances and tests that de viated from those that the pr ocedure applies to such as appliances connected to large mass heat storage systems? Whether it’s a temperature difference measurement issue, a water flow measurement issue, a wood weight and moisture measurement issue or a combination of these, something must have been wrong. No amount of looking at bad data will identify why the data is bad.

6) Table 1 on page 8 is from a test progr am that Intertek conducted. But the data in the table does not match up with the data submitted. Some of the differences are minor, but others are signi ficant. Line 29 on this tabl e (APD) purports to be the
“Actual difference between boiler-side and load-side output” in percent. But the numbers – 200+ % - are clearly not correct. Neither are they simply a case of a misplaced decimal point. The entries for dTload and dTsupply (lines 23 and 24) do not include data for the category II, III and IV test runs although this data was submitted. The “Output Analysis” data shown in Table 2 on page 9 do not match
the data submitted. It is difficult to t ake seriously criticism of labs not submitting complete or accurate data in a report wh ere such obvious errors and omissions are present. These tables make it appear that the data submitted was incomplete when it was not. (See Appendix A for a comparison of the data in the report and the data submitted by Intertek.)

7) The report mischaracterizes the potential error associated with the temperature
difference measurements. The test me thod does require that the temperature
difference measurement be made with in struments that can measure temperature difference to ± 0.5 oF. However, this can only be demonstrated by calibration through measurement of a reference with “known” temperatures that are more accurately measured. This is typically done using water baths held at stable temperatures and measured with certified glass thermometers or precision RTD’s. Thermocouples can meet this specification, but when installed in a dynamic system to measure temperatures of flowing water, additional uncertainties are introduced that cannot be readily quantified. The fact is that we are measuring flowing water with a device that has thermal mass, a la g time, measures a stream which is often non-uniform and changing in temperature, etc. So, while the measurement of temperature difference under static calibrati on meets the ± 0.5 oF specification, in the dynamic system a significantly larger erro r is likely. There is no way of knowing how precise the temperature difference m easurement actually is. There is no calibration process that can directly ve rify the accuracy of the temperaturePage 5 of 10 difference measurement as applied in th e test as doing so would require an independent measurement of the temperat ure difference with a known accuracy significantly better than that of the instru mentation being calibrated. But if we had such a system available, we’d just use it instead of the thermocouples. Of course, any other measurement device would suffer from the same uncertainty issues in the actual dynamic application. So there is something of a “Catch-22” in the test method. That is, the method contains a required measurement precision which cannot be readily verified.

We believe that the thermopile system we have used for some time now has substantially reduced this error. Comp arisons of the temperature differences measured by a thermopile to those meas ured by single thermocouples typically show a difference of several degrees F. It is quite likely that labs could have used thermocouples that met the accuracy requirements based on the calibration requirement of the standard and still have had much larger errors in temperature difference measurements while conducting ac tual tests. While these issues are moot for the future, as the revised method requires the us e of thermopiles, it is still worth noting that this issue is far more significant for measurements of output made on the supply-side of the system wh ere the temperature difference can be only a few degrees F. The ac tual error for measurements made on the load-side of the system has a much smaller impact on th e accuracy of the results due to the much larger actual temperature difference s. And, of course, the revised method
relies on load-side measurements.

8) The authors appear to have misi nterpreted the heat output category requirements of the M28 OWHH procedure. The procedure bases heat output test loads on the “manufacturer’s rated output capacity”. As long as the output achieved in the category IV test is within 10% of the rated capacity, the test load outputs are based on the rated capacity, not the measured category IV output. Thus, if the appliance is rate d at 100,000 Btu/hr, the category IV test result needs to be between 90,000 and 110,000 Btu/hr. The upper limits for the category I, II and II tests are then 15,000, 24,000 and 50,000 Btu/hr respectively. The NYSERDA reports indicate the authors based their c onclusions regarding tests being out of the specified range on the percentage of the m easured category IV test output rather than the manufacturer’s rated output.

It should also be noted that the difference in load-side and supply-side heat output measurement accuracy can result in a test being within the specified category based on one measure, but outside the category on th e other. Labs have been faced with the difficulty of trying to operate at out put rates that would be in the required category using the supply-side inaccurate measurements when they know the
accurate load-side measurement is out side the required category.Page 6 of 10 OTHER COMMENTS

Intertek is surprised to find considerable discussion of issues that are unrelated and
irrelevant to the issue of EPA M28 OWHH test results. These include nearly 9 pages devoted to a discussion of appropriate app liance sizing and weighting factors used to determine average performance and recommendations on technology improvements. These issues are of no consequence in the evaluation of the accuracy of test results submitted based on the original EPA M28 OWHH procedure.

However, since the authors saw fit to di scuss these issues, Intertek will take this opportunity to respond to a fe w of the points discussed.

APPLIANCE SIZING

In section 5.2 the authors go to considerab le length to justify a heavy weighting on the low output test data. For example they state that the average design heat load for a US home is 65,000 Btu/hr while the av erage output capacity of the units in the voluntary program is 175,000 Btu/hr. From this they deduce that hydronic heaters are oversized by a “sizing factor” of 2.7 to 8.8. This is complete hyperbole. Hydronic heaters have been primarily mar keted in the northern mid-west and New England area to farmers and home owners with much higher than average heating requirements. The range of rated outputs of appliances tested by Intertek is 44,700 to 217,000 Btu/hr with 5 of 11around 100,000 Btu/hr or less. A simple check of major gas and oil boiler manufacturers produc t lists indicates all offer residential boilers in output ranges fro m 40,000 to over 300,000 Btu/ hr. European wood fire boilers are offered in sizes typically from 20 to 80 kW (68,000 to 275,000 Btu/hr).

While we understand the concern regarding appliance sizing discussed in 5.1 and 5.2, this has nothing to do with the process or accuracy of rating the appliances. Of course it is inappropriate to install a 175,000 Btu/hr appliance in a building with a 65,000 Btu/hr design heat demand. But it’s perfectly fine for a building with a 175,000 Btu/hr requirement. M28 WHH has nothing to do with consumers buying appropriately sized appliances.

“Sizing factor” is not term used in the HVAC industry that we are aware of. In fact,
HVAC Handbooks such as the ASHRAE Fund amentals devote many chapters to estimating heating loads and selection of pr operly sized heating equipment. In our experience, professional HVAC contractor s are well aware of the appropriate appliance sizing practices.

We would also note that anyone with a de sign heat load of 55, 000 Btu/hr, as used in the example in the paper, has a very small heat demand and likely a small modern home. Not likely to be some one who would invest $8,000-12,000 in a wood fired hydronic heating system. The real ity is these units are attractive to consumers who do have large heat demands – rural, old, large, poorly insulatedPage 7 of 10 houses, small commercial establishments, et c. If heating costs are $1000/mo or more using traditional fossil fuel heating a nd there is a ready ch eap source of wood, these units can actually pay back the investment.

WEIGHTING SCHEME

We would suggest that the issue of weight ing should start with the assumption that consumers should buy appliances that are co rrectly sized for their need. This would eliminate columns labeled 2 and higher in tables 7 and 8. This would then indicate that, if anything, the SR proposed weightings are more severe th an the Syracuse Bin Data profile indicates (heavier weighting on the Category I and II outputs). Column 1 (i.e. correctly sized appliance) of ta ble 8 indicates that the current M28 WHH weighting on category I is way too high (0.437 vs 0.077) and that the heaviest weighting should actually be on the category III results.

We understand that many people seem to think that these units are sometimes used year round since they ar e often installed with an indirect domestic hot water (DHW) heating function. This makes se nse during the heating season as the DHW load can be easily supplied without a noticeab le impact of the building heating. But, this led to the idea that the appliances are operated year round but only to heat DHW in the summer. This is a highly questi onable position. The typical residential water heating demand is around 30,000 Btu per day. Most of this demand takes place during relatively short time frames in the morning and evening. It is doubtful that any of the cordwood fired boilers under discussion would sustain a fire given these low load conditions. In any case, such a low demand when burning full loads
of wood would result in efficiencies so lo w that the waste of fuel would be very obvious. Even heating water with the most expensive traditional fuels which operate at 70% or higher effi ciencies would be far less expensive than heating with
wood where efficiencies would probably be less than 10%.

e.g. Suppose a unit is rated at 100,000 Bt u/hr and is set-up to operate at demands as low as 10,000 Btu/hr. When there is no demand the appliance will continue to produce 10,000 Btu/hr of heat which will be wasted. During a 24 hour period the appliance would thus produce 240,000 Btus of which 30,000 could be used for DHW. 210,000 Btus would be unusable. So, only 12.5% of the heat produced
could be used for DHW. It makes no sense to heat domestic hot water this way.

TECHNOLOGY PROMOTION

The authors take the opportunity to promote the partial heat storage approach as a "proven" method of improving efficiency and emissions (6.5). But there is no hard
evidence for this stance ei ther. What is missing in an understanding of the basic flaw in the concept. It is true that most buildings require less than 25% of a properly sized appliance’s output capacity much of the time. But adding heat storage means that after most fuel loads are burned, the storage will provide heat for many hours after the fuel has been consumed a nd a new fire will need to bePage 8 of 10 started for nearly every operating cycl e. However, emissions produced during ignition of a fuel load without the bene fit of a hot coal bed have rarely been measured. Virtually all existing data is from tests conducted by loading fresh fuel onto a large hot coal bed which generates very quick ignition and initiation of secondary combustion.

Intertek has done several tests of appliances that have very low emissions ratings per the EN 303-5 method using the "cold-st art" procedure proposed for the ASTM standard. The emissions produced while the ne w fuel load is being ignited are quite heavy and last for anywhere from 1/2 to 1 hour. Emissions rates can be over 1.5 lb/mmBtu output, and efficiency under 50%. In short, there is a trade off here – reducing cycling comes at the price of many mo re cold starts. If there is not a well established hot coal bed on the grate when th ese appliances are loaded with fuel, it is doubtful they will perform nearly as well as expected. In our experience, they actually do much better without heat stor age at low output rate s where they cycle on and off and are operated with fuel lo aded on a substantial hot coal bed. NYSERDA in their up-coming research test program should conduct emissions tests with an EN 303-5 appliance with heat storage connected using cold starts, to generate data to address this important issue.

In wood burning appliance emissions testi ng we have always ignored the issue of
"cold-starts" based on the idea that users try to keep their wood stoves or boilers running for many days. Thus, there has al ways been a demand for appliances that will "hold a fire over night". WHH's typically have large fireboxes so that refueling on an existing coal bed can be done at in tervals of 12 to 24 hours or more. As a result, we have produced virtually no da ta indicating how co ld starts affect emissions/efficiency performance. Those of us who have done hundreds of tests
know that we tend to see a lot of smoke wh en we start appliances up to establish the coal bed required for the test runs. But if a fire only has to be started infrequently, it's probably not a very signifi cant issue. The EN 303-5 standard also ignores the start-up issue, but then effectively requires th e use of heat accumulators which guarantees that most fuelings will be cold starts. The disconnect between lab testing and consumer operation shoul d be obvious. But NYSERDA has heavily endorsed the heat storage concept based on European test data and is actively promoting this technology. This seems to bring their objectivity into question when it comes to making recommendations such as those contained in the report.

It should be noted that this is not an i ssue for full storage appliances that meet emissions requirements under Appendix X1 of ASTM E2618 which evaluates the appliance under cold-start operation.Page 9 of 10 Appendix A.

Tables 1 & 2 As Reported by NYSERDA

Category 1. Inputs symbol units I II III IV Description of measurement

Ts F 175 191.3 220.2 377 Average stack gas temperature

E A % 117 200 160 66 Excess air Tsup F 166.9 163.5 167.2 153.7 Boiler supply temperature

Tret F 164.52 156.1 157.11 133.83 Boiler return temperature

Tcw F 83.96 69.17 63.79 57.52 Cold water

Tcwout F 158.08 144.45 146.7 131.56 Cooling water out of heat exchanger

V fls gpm 0.277 0.541 0.659 2.199 load side water flow

V fss gpm 4.18 6.85 8.08 8.61 supply side water flow mp ln/MMBtu 0.29 0.23 0.21 0.05 particulate emissions (supply side)

Eff % 42 78.2 79.4 73 efficiency based on supply side
MC % 19.37 21.13 21.7 21.09 moisture content

dTload F 83.18 load side delta-T dtSupply F 5.2495 Supply side delta-T

dTbs F 5.25 7.4 10.09 19.87 Average boiler side delta-T
2. Calculatrions MPEbs % 11.52 8.76 6.96 4.52 Max error in output (boiler side)

MPEIs % 1.1 1.16 1.1 1.18 Max error in output (load side)

MPD % 12.63 9.92 8.06 5.69 Max difference between boiler side and load side output

APD % 214.69 208.28 206.76 201.37 Actual difference between boiler side and load side output
EffComb % 84.24 81.28 80.84 78.29 Combution efficiency

3. Evaluations 5.25 7.4 10.09 High Supply Side Error Difference between supply side and load side output out of range -1.44 Low combustion efficiency Moisture content out of range

133.83 Low T return

4. Results Average original load side Comb Eff Annual Efficiency 62.5 51.3 82.3 Annual PM lb/MMBtu Output 0.242 0.286 Cat IV Efficiency 73 70.8 78.3

I II III IV 5. Output Analysis 10701 24772 39832 84065 Supply Side Output Btu/hr 10212 20330 27309 81065 Load Side Output Btu/hr 25479 31677 50165 115157 Input Btu/hr 12.7 29.5 47.4 100 Cat output as % of Cat IV - Supply Side 12.5 24.9 33.5 100 Cat output as % of Cat IV - Load Side 40.1 64.2 54.4 70.8 Efficiency based on load side

<15 16 to 24 25 to 50 Rated Cat % Output Range from M28

6. Correction for Mass, dT -4.93 -1.3122 0.3507 -15.2348 Unit Temp Change F 561.1 Capacity Btu/F 1150 704 541 235 duration (min) 10557 24709 39853 81882 Adj Supply Side Output Btu/hr 10068 20267 27331 79319 Adj Load Side Output Btu/hr 12.9 30.2 48.7 100 Cat output as % of Cat IV - Supply Side 12.7 25.6 34.5 100 Cat output as % of Cat IV - Load Side 39.5 68777.3 57682.3 79318.7 Efficiency based on load side -1.4 -0.3 0.1 -2.7 % change in load side output due to mass,dt correctionPage 10 of 10 Table 1 & 2 Revised to include the data as submitted by Intertek

Intertek Note: It was recogniz ed during this program that the category II and III tests showed a large difference between the load and supply-side re sults. We did propose to report the results
based on the load-side data which we considered to be accurate. However, since the test method required reporting based on t he supply-side data, the report was issued on this basis to comply with EPA requirements. ACTUAL DATA SUBMITTED Green highlighted data within 2% of NYSERDA Report Red highlighted data more than 2% different than NYSERDA

Category 1 Inputs symbol units I II III IV Description of measurement

Ts F 174.37 191.61 218.38 379.39 Average stack gas temperature

E A % 100 222 204 66 Excess air (B415) Tsup F 166.9 164.55 167.2 153.7 Boiler supply temperature

Tret F 164.52 155.99 157.11 133.83 Boiler return temperature

Tcw F 83.96 69.17 63.79 57.52 Cold water

Tcwout F 158.08 144.45 150.48 131.56 Cooling water out of heat exchanger

V fls gpm 0.277 0.461 0.603 2.199 load side water flow

V fss gpm 4.180 6.850 8.080 8.610 supply side water flow mp lb/MMBtu 0.289 0.233 0.21 0.048 particulate emissions (supply side)

Eff % 42 78.2 79.4 73 efficiency based on supply side
MC % 19.37 21.13 21.7 21.09 moisture content

dTload F 83.18 75.28 86.69 74.05 load side delta-T dtSupply F 5.2495 8.561 10.05 19.87 Supply side delta-T

dTbs F 5.25 8.561 10.05 19.87 Average boiler side delta-T
2. Calculatrions MPEbs % 11.52 7.84 6.98 4.52 Max error in output (boiler side)

MPEIs % 1.10 1.16 1.08 1.18 Max error in output (load side)

MPD % 12.63 9.00 8.05 5.69 Max difference between boiler side and load side output

APD % -7.14 39.52 34.04 2.81 Actual difference between boiler side and load side output
EffComb % 74.41 73.88 72.12 78.37 Combution efficiency (B415)

3. Evaluations 5.25 8.561 10.05 19.87 High Supply Side Error -6.7% 65.3% 51.6% 2.9% Difference between supply side and load side output out of range 29.5 26.4 19.4 5.5 Low combustion efficiency 19.37 21.13 21.7 21.09 Moisture content out of range 164.52 155.99 157.11 133.83 Low T return (<125 F)

4. Results Average original load side Comb Eff Annual Efficiency 62.5 49.1 73.9 Annual PM lb/MMBtu Output 0.242 0.3 Cat IV Efficiency 73 70.8 78.3

I II III IV 5. Output Analysis 10,698 28,695 40,137 85,151 Supply Side Output Btu/hr 11,452 17,381 26,465 82,822 Load Side Output Btu/hr 25,479 36,631 50,165 113,709 Input Btu/hr 12.7 29.5 47.4 100 Cat output as % of Cat IV - Supply Side 12.5 24.9 33.5 100 Cat output as % of Cat IV - Load Side 44.9 47.4 52.8 72.8 Efficiency based on load side

<15 16 to 24 25 to 50 Rated Cat % Output Range from M28

6. Correction for Mass, dT -4.93 -1.3122 0.3507 -15.2348 Unit Temp Change F 561.1 Capacity Btu/F 1150 704 541 235 duration (min) 10,554 28,632 40,159 82,968 Adj Supply Side Output Btu/hr 11,308 17,318 26,487 80,639 Adj Load Side Output Btu/hr 12.72 34.51 48.40 100 Cat output as % of Cat IV- Supply Side 14.02 21.48 32.85 100 Cat output as % of Cat IV - Load Side 44.38 47.28 52.80 70.92 Efficiency based on load side -1.26 -0.36 0.08 -2.64 % change in load side output due to mass,dt correction