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January 20, 2015

Ms. Brenda Edwards 

U.S. Department of Energy 

Building Technologies Program, MS EE-5B 

1000 Independence Avenue, S.W. 

Washington, D.C. 20585-0121 

Re: Raypak Comments on the Preliminary Technical Support Document on Commercial Packaged 

Boilers

Docket No. EERE–2013–BT-STD–0030

Dear Ms. Edwards, 

Raypak is a manufacturer of Commercial Boilers, Commercial Water Heaters, Residential Boilers, Gas 

Pool Heaters and Heat Pump Pool Heaters with facilities in Oxnard, CA and Ft. Myers, FL. We submit 

the following comments in response to the preliminary Technical Support Document (TSD) issued in the 

November 20, 2014 Federal Register and the Executive Summary of this analysis which included a list of 

questions and concerns related to the rulemaking on which DOE is seeking information or data. 

General Comments:

Raypak is concerned that the lack of a finalized revised efficiency test procedure (as DOE indicated at the 

December 9, 2014 public meeting that it expected to issue the Notice of Proposed Rulemaking (NOPR) 

for revising the efficiency test procedures for commercial boilers sometime in the next few months and 

prior to the NOPR for this efficiency standard rulemaking) will adversely affect the ability of DOE (and 

all interested parties) to properly evaluate potential efficiency standard changes. Raypak believes that 

DOE should NOT conduct these 2 potential rulemakings in parallel, but should decide if changes to the 

efficiency test procedure will be done and then finalize that rulemaking before embarking on energy 

standard changes. It is impossible to evaluate the effect that various design options might have on 

efficiency and energy savings if the test procedure changes. We no longer have a baseline efficiency 

model if changes in the test procedure adversely affect the measured efficiency. If this means that DOE 

must delay the efficiency standard rulemaking because of this conflict, it should be done.

Raypak understands that there is a newer 2012 Commercial Building Energy Consumption Survey 

(CBECS) that has not yet been officially published. The use of data from the CBECS is the critical 

component to the estimated annual energy consumption values used in this analysis. This rulemaking will 

be affecting boilers manufactured in 2019 and beyond and the advances in commercial building 

construction to reduce energy consumption will not be recognized if the 2003 CBECS data is used. The 

continued use of 2003 CBECS data will not properly present the energy use of commercial boilers being 

installed in 2019 and beyond. If this means that the DOE rulemaking must be delayed to await the 

official publication of the 2012 CBECS, it should be done.
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Comments on Executive Summary Questions:

Question #2 - DOE requests comment on the appropriateness of its tentative decision to classify CPBs 

into 16 equipment classes as described in Table ES.3.2. 

Raypak believes that the current 10 equipment classes are appropriate. The addition of separate product 

classes for natural draft gas and oil boilers is unnecessary as the industry has recognized that natural draft 

boilers have been a covered product under EPAct for the many years. There should be no question that 

natural draft commercial packaged boilers are covered equipment subject to the DOE’s efficiency 

standards. 

Question #3 - DOE seeks comment on CPB standby mode and off mode energy consumption and, in 

particular, data on the magnitude of energy consumed in the different operational modes. 

Raypak supports the preliminary finding that standby mode and off mode energy consumption of 

commercial boilers is a very small percentage of the total boiler energy usage. The magnitude of the 

energy consumption as noted in the analysis at 0.02% of the total energy consumption is negligible and 

we recommend that DOE not pursue the development of standby and off mode energy conservation 

standards for commercial packaged boilers.

Question #4 – DOE is interested in views regarding the technological and economic feasibility of the 

technology options which successfully passed the screening analysis. In particular, DOE seeks 

information regarding technology options which can be applied to improve the efficiency of natural draft 

boilers. 

Raypak generally agrees with the list of options that successfully passed the screening analysis in the TSD 

with the exception of pulse combustion. Pulse combustion is simply a boiler design that some 

manufacturers have chosen to pursue. It is no different than choosing a water-tube versus fire-tube 

design. This choice is just something that manufacturers chose when designing boilers for market use. 

Many of the options listed are already employed by manufacturers to attain their current efficiency 

ratings. DOE needs to be very careful in their assumptions that these can continue to be increased to yield 

higher efficiency levels. Any additional restrictions of the heat exchanger MUST be balanced to ensure 

the safe operation and venting of the boiler. It is very possible that these design options have been 

maximized and there is little or no opportunity to increase these beyond current ratings.

Question #8 - DOE welcomes suggestions and comments concerning its proposed approach to 

developing estimates of future commercial packaged boiler retail prices. 

Raypak believes that the approach to start with the cost of a mechanical draft model and subtract the cost 

of components that would not be employed on a natural draft model to estimate the price of a natural draft 

model is severely flawed. It does not account for different components and construction that would be 

found on a natural draft models but which are not used on mechanical draft models. Examples include 

flue or vent dampers and draft hoods that are used on natural draft models but not mechanical draft 

boilers. In addition, the burner designs for natural draft boilers are significantly different than mechanical 

draft boilers and the cost differences cannot be estimated from this subtraction process. We encourage 

DOE to contact contractors and others involved in selling and installing commercial boilers to obtain 

more information on retail prices for natural draft models. Raypak notes that the analysis currently 

extrapolates prices assuming a linear relationship between input rate and price. That assumption is 

incorrect. As boilers get larger in input, the cost of gas, burner and blower components is almost 
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exponential. The volumes of these components is much smaller and more specialized with fewer 

manufacturers supplying these components and hence the prices are significantly higher.

Question #10 - DOE seeks data on representative annual profiles of return water temperature, supply 

water temperature, and boiler percent loading. 

Raypak notes that this information is unique to every boiler application, building design and engineering 

plans for building operation. In essence there is no such “typical” or “representative” profile that can be 

submitted. ASHRAE 90.1 is employed in building system requirements and as long as those minimums 

are met, anything else is a function of the design.

Question #11 - DOE seeks data on what return water temperatures boilers are tested at under the test 

conditions prescribed by the DOE test procedure. 

Raypak notes that the range of return water temperature ranges provided in the BTS-2000 standard are 

meant to address the wide range of ground water temperatures available throughout the year across the 

country. This allows manufacturers to test products without excessive and expensive means to heat/cool 

water for efficiency tests. Since this range of temperatures is available through the BTS-2000 standard, 

manufacturers will test at the temperature which provides the best results under the current test procedure.

Question #13 - DOE welcomes any data from interested parties about typical boiler sizing practices, 

including how often multiple boilers instead of a single boiler are installed to cover the building heating 

load, and how the number of boilers suitable for a specific installation is determined. 

Raypak notes that there is no such thing as “typical” boiler sizing practice. As noted earlier in these 

comments, engineers, architects and designers are responsible for creating buildings the way the owner 

desires. However, Raypak believes that trends show that more buildings, new and existing, are being 

provided with multiple smaller boilers instead of a single larger boiler. Raypak believes that some of this 

trend is to allow for better system operation during the “shoulder months” of the year when a large boiler 

would be operating a very small part of the time, but would have many cycles. Using smaller boilers 

allows better load tracking for the system requirements. It should also be noted that ASHRAE 90.1-2013 

now requires all boiler systems with an input rate of 1MM Btu/hr or more to have an input turndown ratio 

of at least 3:1. It goes on to note that this turndown ratio can be accomplished by the use of modulating or 

multi-stage boilers or by multiple single stage boilers. 

Question #14 - DOE seeks input on how boilers are controlled, particularly in multiple-boiler 

installations. 

Raypak notes that there are a variety of control systems used to control multi-boiler systems. Some of 

these are provided by the boiler manufacturer. Some systems, such as building energy management 

systems, are independent of the control system provided on the boiler. Raypak notes that an assumption 

used by DOE in the analysis involves that when multiple boilers are used on a job – they are exactly the 

same type and size. This assumption is incorrect. Raypak is seeing much more of “Hybrid” type systems 

which include both condensing and non-condensing boilers on the same system. This is to take advantage 

of condensing (when possible) and then use the non-condensing at the height of the boiler season when 

system temperatures may be much higher than normal due to outdoor reset functionality of controls. 

These systems also include the use of controls which know the return water temperature and bring on 

condensing boilers when possible to maintain the highest system efficiency.
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Question #15 - DOE seeks historical shipment-weighted commercial packaged boiler efficiency data 

and/or shipment data by efficiency bins. DOE is primarily interested in data during the last 10 years in 

order to capture the impact of the most current technologies on the boilers market. 

Raypak does not currently have the requested data, however, we make note that 10 years ago, Raypak had 

a single boiler system that was condensing. Today, we have 6 series of boilers that are condensing. This 

increase in demand for condensing boilers is due to market demands. It has nothing to do with minimum 

efficiency standards as set by DOE. The market is moving in the direction of more condensing boilers 

because of the inferred energy and cost savings. However, Raypak also is aware of many installations 

that have been installed with condensing boilers (due to rebates offered for installation of condensing 

boilers or the hopes of energy savings due to higher rated efficiencies), but the system temperatures will 

not allow condensing to take place and so the desired savings will never be fully realized. The use of 

condensing boilers can only realize the anticipated savings if the entire system is set up to work with the 

lower temperatures required in condensing systems. DOE should be aware of this issue about installing 

condensing boilers without having a distribution system capable of properly operating with the lower 

boiler water temperatures as needed for condensing system to yield the maximum cost/energy savings. In 

replacement markets, replacing a non-condensing boiler with a condensing boiler without making changes 

to the distribution system will yield little or no cost/energy savings.

Question #16 - DOE requests input on ancillary energy use by commercial boilers (i.e., in addition to fuel 

energy use) that should be included in the energy use analysis. 

The BTS-2000 test procedure does not account for electrical consumption in the measurement of Thermal 

Efficiency or Combustion Efficiency, so there is no use in collecting this information. Also as noted 

earlier in these comments, the electrical consumption of commercial boilers (both standby and OFF mode 

electrical consumption as well as operating electrical consumption) is small in comparison to the gas/oil 

energy consumption of these commercial packaged boilers.

Question#17 - DOE seeks input on what fractions of hot-water commercial packaged boilers are used 

both for space heating and hot water. 

Although we have no specific data, Raypak believes that the fraction of hot-water commercial packaged 

boilers used both for space heating and hot water is far less than the 50% assumed in the analysis. While 

this is very popular for residential condensing boilers in Europe and other parts of the world, this is not 

practiced very often in commercial boiler applications in the US. In addition, there is additional 

efficiency losses by running the boiler water through a heat exchanger to supply hot water and these 

losses can be mitigated by using separate water heating systems (either individual point-of-use or storage 

tank water heaters or large system water heaters with separate storage tanks). The one exception to this 

might be on steam systems where water heating can be provided as one of the zones.

Question #19 - DOE requests comment on frequency and cost of maintenance, major repair issues, repair 

frequency, and repair costs for commercial packaged boilers that meet the minimum efficiency standards, 

as well as for higher-efficiency boilers. 

Raypak believes that the frequency and cost of maintenance, major repairs, etc. presented in the analysis 

may be representative of older technology boilers. However, newer technology boilers (condensing) 

requires a higher level of expertise from technicians, specialized equipment and hence a higher cost of 

service/repair. Additionally as noted earlier in these comments, DOE should not assume that there is a 

linear relationship between the size of the boiler and the costs of its components. 
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Question #20 - DOE seeks input on how often boiler maintenance is performed by on-site staff versus 

external contractors, specifically for hot water boilers versus steam boilers and small boilers versus large 

boilers. 

Raypak has no data on this, but we believe that the vast majority of maintenance/service is performed by 

manufacturer factory trained personnel due to the specialized equipment and expertise required to 

properly diagnose and repair current commercial packaged boilers. There may a list of general 

maintenance items that can be accomplished on –site (checking for blockages in vent/air intake, looking at 

burner flame and notifying service company if changes take place, maintaining and adjusting water 

quality as required, etc) but little else.

Question #21 - DOE seeks input as to how often, in the event of a heat exchanger failure, the heat 

exchanger alone is replaced versus the entire boiler being replaced. DOE is interested in knowing whether 

this varies with equipment class or varies with condensing versus non-condensing boilers. 

Raypak has no reliable data to provide an answer for this. If a heat exchanger fails under warranty, the 

manufacturer would know whether it was replaced versus the entire boiler. However, for heat exchanger 

failures out of warranty, the manufacturer has no knowledge of whether the heat exchanger was replaced 

or the boiler replaced. A replacement heat exchanger would show up simply in replacement parts orders 

and a replacement boiler would show up simply as a boiler shipment.

Question #23 - DOE seeks input on how often plastic versus stainless steel venting is installed for 

condensing boilers. 

Raypak notes that this decision is really a function of system design and boiler location. However, there 

is a size limit for plastic venting. When the required vent size is 8” or larger the vent is typically stainless 

steel because plastic vent materials (ULC S636 certified) are not readily available in these larger sizes. 

When the required vent size is 4” or smaller, plastic vent materials are often used. Sizes in between are 

really a function of the boiler system design, vent length, configuration, etc. The most economical vent 

materials are generally used in these intermediate sizes.

Question #24 - DOE seeks input on how often boilers have direct venting, for both condensing and noncondensing boilers. 

Raypak is confused as to why DOE is asking for this information. Direct venting has nothing to do with 

boiler efficiency. Many mechanical draft boilers and some natural draft boilers are designed to 

accommodate standard venting or direct venting depending on the installation requirements, but the 

manufacturer will have no idea as to the percentage installed either way. Raypak also has many boilers 

which are designed for outdoor installation, so that is another venting configuration not addressed by 

DOE.

Question #25 - DOE seeks input on the fraction of stainless steel venting in existing boiler installations 

by efficiency. 

For existing installations of commercial boilers with efficiencies below condensing, stainless steel venting 

is rarely used. Stainless steel venting is much more costly than standard “B” vent which is used for most 

non-condensing boilers vented in Category I venting configurations. However, many boilers are designed 

for Category I if vented vertically and Category III if vented horizontally. In this case, stainless steel 

would be used for horizontal vented boilers in order to comply with categorization requirements for 
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boilers. However, the manufacturer has limited to no knowledge of the final installation and whether the 

boilers are vented vertically or horizontally.

Question #26 - DOE seeks input on where boilers are typically located within buildings and where the 

vents typically terminate. DOE is interested in whether such placements change by geographic region or 

boiler type. 

As noted previously in these comments, there is really no such thing as a “typical” boiler installation. 

Boilers can be located in the basement, mechanical room, penthouse or outdoors. In high-rise buildings 

boilers are often located on intermediate floors because of other system limitations.

Question #27 - DOE seeks data on how often common venting occurs in multiple-boiler installations and 

whether commercial water heaters are commonly vented with commercial boilers. 

The National Fuel Gas Code (NFGC) addresses common venting of non-condensing Category I 

equipment. When it comes to common venting of condensing boilers or other Category boilers), the 

NFGC calls for “Engineered Vent Systems”. This requires a Registered Professional Engineer to sign off 

on the vent system design when combining multiple condensing boilers into a common vent. This adds 

cost for the design, PE stamp and equipment over and above the cost of the vent materials alone. Again, 

the boiler manufacturer does not know how often this occurs because they are generally not associated 

with the end installation.

Question #28 - DOE seeks comments on the methodology used to determine equipment lifetimes for 

commercial packaged boilers. 

Raypak notes that the assumption developed by DOE in the analysis of an average life of 24.8 years for 

BOTH non-condensing and condensing boilers is incorrect. There are two distinct classes of gas 

commercial packaged boilers on the market today - non-condensing and condensing. While there is 

sufficient history to warrant determining an average life for non-condensing boilers, there is insufficient 

history to make that determination for condensing boilers. Condensing boilers have only been on the 

market for about 15 years, so to use an average life of 24.8 years in the analysis is unwarranted. Raypak 

believes that the average life of condensing boilers will be in the neighborhood of 15 years based on the 

history that we have seen to date.

Question #31 - DOE requests data on the efficiency distribution and welcomes comment on the 

likelihood and degree of improvement in efficiency of commercial packaged boilers in the next 5 to 10 

years as a result of market forces or industry trends (in the absence of amended energy conservation 

standards). 

Raypak does not have data available on the efficiency distribution as requested as previously noted in our 

comments to Question #15. However, we believe that the market will continue to push for condensing 

systems as a cost/energy saving opportunity. There will be little improvement in efficiency from current 

condensing boiler levels due to the fact that manufacturers are approaching max tech efficiency levels. 

There will be other things that the marketplace will start using besides efficiency to decide between 

products available on the market. These include diagnostics information, communications, plug-n-play 

installation, system design and system efficiencies, etc. However, DOE also needs to be aware that noncondensing boilers are still a significant part of the market due to (1) simpler operation and maintenance, 

(2) higher design water temperature in the application that would not benefit from condensing boilers, (3) 

lower first cost and installed cost, (4) longer anticipated product life, (5) significant costs of retrofit to 

change to condensing boilers, among others. It is due to these and other concerns that Raypak would like 
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to encourage DOE to maintain the atmospheric or natural draft boiler classification and that efficiency 

levels are not adjusted to a level which would not be able to support this very important product 

classification. The largest part of the commercial packaged boiler market is replacement. Many of the 

existing installations are not suitable for condensing boilers and therefore the market needs to maintain 

this classification of boilers.

Question #35 - DOE seeks input on the potential impact of amended standards on commercial packaged 

boiler shipments.

Raypak believes that incremental increases in the standard are not likely to have significant effect on 

shipments. Large increases in the standard will likely result in lower shipments since more existing 

installations will choose to repair the boiler rather than replace it when the existing boiler is not operating 

properly. This is particularly true if the large increase results in the elimination of the atmospheric, 

natural draft classification of boilers.

Raypak appreciates this opportunity to provide comments and participate in this rulemaking. We will be 

open to discuss any of the comments presented here at your convenience.

Respectfully submitted,

Robert S. Glass

Sr. Staff Engineer

Raypak, Inc., 2151 Eastman Avenue, Oxnard, CA 93030 (805) 278-5300 FAX (800) 872-9725 • www.raypak.com