Letters to the Editor

The least you can do

This letter refers to Rebecca Ellis’ “Commissioning” column titled, “The Least You Can Do,” in the April 2007 issue of Engineered Systems (page 20).

The variability in the definition of commissioning services presents significant problems for construction managers (CM) developing early phase cost models for complex projects like hospitals. The subject appears overwhelmingly complex to the project team and scope definition lags. The owner may not have the opportunity to discuss specific expectations leading to the unpleasant surprises suggested by the article.

We recommend that the initial RFP for commissioning services be a qualifications, task, estimated effort and rates proposal for a commissioning agent to work with the project team on an hourly basis with a not-to-exceed maximum through schematic design. This will define the owner’s commissioning expectations and develop task descriptions with estimated effort for the remainder of the project. The owner can then negotiate the additional services with the on-board CxA or offer an open procurement based on a fully developed scope of work. Once the commissioning ex-pectations have been expressed, the construction manager can properly forecast the required effort by the trades and CM staff ensuring adequate resource to meet the owner’s requirements.

James W. Moler P.E.
Manager, Engineering Systems

LEED® Accredited Professional

Turner Healthcare, Brentwood, TN

Ellis responds:

Your proposed approach is excellent and one that has proven both effective and efficient for project teams and building owners alike. I recommend taking the hourly commissioning services even further, i.e., through the design development phase. Theoretically, it is at that stage of the project that the systems to be commissioned can be defined and quantified and are not likely to vary significantly through the completion of design docu-ments. This represents less risk to both the commissioning agent and owner when negotiating or otherwise pro-curing continuing commissioning services.

In either case, the key is understanding that it takes time and effort to define an appropriate and affordable scope of commissioning for each project and that process needs to occur before project planning/budgeting moves too far into design.

Identifying the minimum definition of commissioning

I recently caught up on my reading, and read Rebecca Ellis’ April 2007 “Commissioning” column.

I feel that she is absolutely correct with this article and has identified a problem with commissioning - one that could affect the future of the commissioning discipline.

New commissioning companies are getting into the market with the thought that providing the commissioning service will be an easy cash cow for their company’s bottom line. When these companies first get into the market, they may not have the organization, knowledge, or technical ability to provide the total commissioning service required.

If the owner is unaware of what the total commissioning process encompasses, they may choose an organization that doesn’t provide the total commissioning service and process - and they may choose them based on lowest fee. If the Commissioning Authority then doesn’t perform (because of potential cost and losses to the firm), the owner will have a negative attitude towards commissioning. The owner may then provide this negative feedback to other people in the particular peer group - to the detriment of the commissioning discipline overall.

ASHRAE has provided an excellent guideline for commissioning. In order to continue with a complete commissioning service, the commissioning community (with all the varying organizations and guidelines) must somehow come together and adopt the ASHRAE or similar guidelines as standards. These standards will allow existing, as well as new, commissioning firms to provide a complete service that is equal in quality of process to each other. An owner seeking commissioning services could then be more comfortable that he is choosing a firm based upon the quality of the organization - not just a low price that may not provide the service the owner needs.

Frank A. Mauro, P.E., LEED AP, CCP
Commissioning Project Manager
Heapy Engineering LLC
Dayton, OH

Ellis responds:

Thank you very much for your affirming e-mail. These are very interesting times for the commissioning industry. I am pleased, as I hope you are, that there are still a good number of owners who care about the quality of commis-sioning they receive and are doing their due diligence when selecting professionals to help them through the process.

Using ground source heat pumps

This letter refers to Howard McKew’s “Back To Basics” test that appeared in the April 2007 issue, pages 10-11.

I’m not being picky, but air separators are always “in high, out low.” Also, I would put the ground water temperature transmitters on the common line to the heat pumps and in the separate lines on the outlet, in the same number, but arranged like you have it on the building side.
I am a big fan of the concept, but have a couple of questions.

How do you control the fancoils to get good dehumidification?
What manufacturer of heat pump are you using?
How do you bill the condo owners?
Is dirty water an issue?
Is re-injection an issue?

Thomas (Tom) H. Durkin, P.E.
Durkin & Villalta
Partners Engineering
Indianapolis, IN

McKew responds

Design of ground source heat pumps systems seems to be catching on in New England, but my experience has been on the commissioning side. What I’m seeing is design engineers are depending on well-pump vendors for their condenser water design, and as a result, a lot of details fall through the cracks.

How do you control the fancoils to get good dehumidification?
You really don’t get good dehumidification, but in New England that usually isn’t a big problem. The applications we have been commissioning have been colleges and commercial developers, for whom dehumidification hasn’t been a design requirement.
What manufacturer of heat pump are you using?
As the commissioning engineer, we leave that up to the design engineer, but they pretty much specify the regular heat pump manufacturers in the 3- to 5-ton unit size range.
How do you bill the condo owners?
I have never asked this, and for the most part the projects have been on college campuses except one developer (and that job isn’t completed yet).
Is dirty water an issue?
Yes, on the well-water side, this and the quality of the water are both problems.
Is re-injection an issue?
At one job site, this was a problem as far as it was affecting the ground temperature.

Casket Bastards

In the May 2007 issue, Matthew Bishop, in his article titled, “Clearing the Smoke,” provided the ultimate type of frustration for tech readers: unexplained acronyms. He mentions UULK-listed fans and alarm systems along with the more familiar UL listing. After checking Google, NFPA, and UL websites as well as those of several other known certification and listing agencies I came up with zero hits to explain or clarify what this person is writing about. Since he claims it’s important and I work with smoke management systems, it’s something I would like to be aware of. He left a dearth of contact information at the end of his article I have only you to ask: What is a UULK listing?

John Weaver
Assistant Chief Engineer
Wells Fargo Concord Center
Concord, CA