Designing and Specifying Precision High Efficiency Heating Equipment:

Installation Training and Certification Pays Off

Plumbing and heating contractor Jerry Davis and mechanical engineer Tim Souza live and work on opposite sides of the country, but they are both strong advocates of proven, compact, high efficiency wall-hung boiler systems. They also share an appreciation for installation training and certification as a key success factor for any mechanical specification.

“We only design and install 90%-plus, propane-fired equipment,” says Jerry Davis, vice-president of of Dubben Brothers, a hydronic heating contractor and propane supplier operating out of a 106-year-old plumbing hardware store serving the Catskill region of New York state. The firm is in its fifth generation of family ownership, and it still operates out of its original storefront location at 90 Main Street in Delhi, NY.

“We have 17 employees, seven of whom are top-notch plumbing and hydronic heating contractors dedicated to the installation and 24/7 repair of heating systems that we design and build ourselves. The bulk of our installation business is the replacement market, as well as new second homes for customers from the New York metropolitan area,” says Davis, whose firm also often provides advisory services for specifying engineers in the region.

Tim Souza is a principal at TEP Engineering, a Santa Rosa-based mechanical engineering firm serving a diverse clientele base throughout the San Francisco Bay Area. His firm includes six mechanical engineers, as well as staff with over 60 combined years of HVAC and plumbing contracting experience.

“We incorporate high efficiency heating and domestic water systems in our project designs and specifications because of the substantial energy savings they produce,” says Tim Souza. “They help us meet demanding Title 24 energy compliance and new California green building code requirements. Additionally, the Baxi combi boiler units save precious floor space by combining the hydronic heating and domestic water production into one compact unit.”

The similarities and shared values of the two firms also include their preferred high efficiency boiler (Baxi), and what they expect in an installing contractor’s qualifications (factory training and certification).

Valuable space savings and dramatic cuts in fuel use and emissions

The introduction of higher efficiency and more compact hydronic heating equipment is bringing North America closer to European high acceptance for wall-hung boiler technology. Substantial fuel consumption, utility bill and valuable space savings make fully modulating, condensing wall-hung boilers, such as the Baxi Luna line, a compelling choice for both new home and retrofit applications.

Baxi wall-hung boilers are compact heating appliances that save up to 60% in fuel use and utility bills, cut greenhouse gas emissions up to 90%, and free up valuable living space. Baxi boilers are closet installation approved and are whisper quiet (45 dBa), making it a preferred appliance in flood-prone areas. The boilers can be used for infloor radiant, snow melt, heated towel racks and radiators, as well as forced air use with a hydronic air handler.

“Our supply house in Oneonta (Irr Supply, the exclusive Upstate New York distributor of Baxi products) introduced us to the Baxi high efficiency product line. We were impressed that it was market-tested, and we attended two technical training sessions put on by the manufacturer before making our first Baxi Luna HT combi boiler installation in September 2006.

“Our first Baxi was in a new home built by a European United Nations diplomat,” says Davis. “It was an easy sell, as the customer was familiar with the product. We have never had a service issue with this unit.”

Over the past six years, Dubben Bros has installed every model of Baxi high efficiency boiler, as well as Baxi solar water heating systems and high output designer radiators.

Tim Souza also discovered Baxi heating solutions around the same time as Dubben Bros. He has specified Baxi combi boiler for affordable housing authority communities in Santa Rosa, among other projects he is designing and specifying.

“The California Energy Code requires that mechanical systems for affordable housing projects beat standard energy code requirements by at least 15%,” says Souza. “The Baxi Luna HT 380 combination heating and domestic hot water boiler, for instance, enabled us to beat standard requirements in most cases by 60% for space heating and 45% for domestic hot water.”

Four decades of wall-hung boiler technology leadership

A leading European heating manufacturer since 1867, Baxi has been at the forefront in developing wallhung boiler technology over the past four decades. Baxi manufactures 4,000 boilers a day for export to 70 countries, including the United States.

Up to 98% energy efficient, the low-NOx Baxi Luna HT light commercial range includes three fully modulating, condensing heating-only models, ranging in high output of 153 MBtu/h and 348 MBtu/h. Twelve Baxi commercials boilers may be strung together, using a staging controller, to produce a total output of up to 4.2 MMBtu/r. System redundancy and impressive turndown ratios make this wall-hung system attractive for commercial applications. All Baxi boilers are shipped from the factory set up for natural gas; they are easily converted to propane, using the QAA73 controller made for Baxi by Siemens.

All Baxi boilers are Energy Star rated and CSA approved, and the heat exchanger bears the ASME H-Stamp. The North American line also includes fully packaged residential models (112 MBtu/h down to 32 MBtu/h output), available in combination heating and domestic hot water (Baxi Luna HT 380), or heating-only mode (Baxi Luna HT 1.33). The combi model can heat a home up to 5,000 square feet and produce 3.9 USGPM (at an 80-degree temperature rise).

Baxi engineers have included multiple built-in safety features – from electronic, gradual ignition (no standing pilot light/no open flame), high temperature limit (set with supplied QAA73 controller made by Siemens), flue high limit switch, central heating high limit switch, fan pressure switch, differential pressure switch, flame sensing electrode and a redundant gas valve plunger (that activates if the primary plunger fails), to back flow prevention devices, Grundfos pump with air vent, expansion tank, frost protection, automatic self-diagnostics and a Legionella prevention function.

Product support and familiarity breed content

“We have not installed any other brand of gas boiler since we switched to Baxi,” says Jerry Davis. “We like the product’s reliability, versatility for new or retrofit applications, venting options, ease of service, the factory training, product certification and in-market trouble shooting provided by our Baxi reps (J and K Sales). We get good support from Irr Supply, as well as Marathon International, the North American distributor of Baxi products”

Dubben Bros staff members are all thoroughly familiar with Baxi product. They have all attended Baxi training, and are installer certified, using an interactive Baxi training and certification CD-ROM. In addition, six of the firm’s employees have a Baxi installed in their own homes, and others are planning to follow suit.

“Efficiency, low sound levels, size, versatility, serviceability and reliability are all key factors in picking the right high efficiency boiler,” says Tim Souza. “The manufacturer‘s ongoing support of the product is also essential, notably in a multi-family application. Other important factors include the availability of contractors who are familiar with the product, factory trained and certified for installation and maintenance.”

The California Green Building Code (Section 702, Installer and Special Inspector Qualifications ) stipulates that “HVAC system installers shall be trained and certified in the proper installation of HVAC systems including ducts and equipment by a nationally or regionally recognized training or certification program,” including manufacturer-approved training and certification programs.

Jerry Davis says his firm believes that any mechanical system specification for a high efficiency boiler system should include a requirement that installing technicians be factory certified in order to bid on a project, “even if that qualification is not a state requirement.”