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The Saga of
The following is a true story of a control systems installation gone awry. *Only the names have been changed to protect the innocent (and the guilty!).
First, a little background. The project consists of
two structures; a parking garage and a residential tower (hi-rise condos). The
parking garage has four levels, with each level having a ventilation system
consisting of intakes, exhaust fans, and carbon monoxide (CO) detectors. The
residential tower is 48 stories including the mechanical penthouse. The ground
level is primarily lobby and dock areas. The second and third levels consist of
equipment rooms, general offices, and amenities spaces such as a fitness center
and a club room. Levels four through 46 are strictly residence levels, with six
residential units per floor, served by four-pipe fan coils. Levels 47 and 48 are
the mechanical penthouse. Within the penthouse are the water cooled chillers and
associated pumps, and the hot water boilers and associated pumps. Outside of the
penthouse are the cooling towers. Other equipment, such as make-up air units and
exhaust fans, round out the HVAC systems and equipment within the building.
Sure-Mech Mechanical* (mechanical contractor) awarded the project to a local controls contractor, Rapid-Con Automation*. The project was sold with an electrical installation budget of 70k. The control systems were subsequently designed and the submittals were prepared by Rapid-Con, and sent through the typical channels (mechanical contractor – general contractor – architect/engineer). The project was semi-negotiated and referred to as “design/assist”; a specification was created yet there was leeway as to its final interpretation. So the project was not pure “plan & spec”, yet not really “design/build” (somewhere in between).
Rapid-Con does not directly employ installation electricians, so as the submittals were in for review by the engineer, the submittal package was also given to several electrical controls installation contractors, in that they might generate a proposal for the work. The numbers started coming in, however none were even close to the installation budget. In fact, the numbers ranged from 150K to 400K!
As the project was “design/assist”, Rapid-Con elected to revise the scope and attempt to cut some costs out of the project, without compromising the integrity of the design. Some of the items addressed in the redesign are as follows:
The specified minimum allowable conduit size was ¾”. The redesign took the liberty of re-specifying it to be ½”.
There was to be a hard-wire network communication cable connecting the penthouse level systems with the ground level systems. The redesign eliminated this cable, and based the communication between upper and lower level systems on tying into and using the building’s Local Area Network (LAN).
The parking garage consists of four levels, each level specified to have 15 carbon monoxide (CO) detectors. The redesign based the CO detection system on using wireless technology, however that idea was scrapped considering that interpretation of city code was unclear as to its acceptability.
And so Rapid-Con charged the low bid electrical
contractor, Best-Elec Power & Control*, to revise their number based upon the
redesign. And they did. However the number only came down by a few grand, and
still was nowhere near the installation budget.
Weeks go by as Rapid-Con tries to figure out how to further reduce the installation burden. When all was said and done, Best-Elec had gone through six iterations of their quote, with revision six being the final quote and the one that Rapid-Con had reluctantly settled upon. The subcontract was awarded, and Best-Elec was told to “hit the job running”.
That same week, the general contractor called for a “temperature controls kickoff meeting” in their trailer onsite. The meeting consisted of representatives from the general contractor, the mechanical contractor (Sure-Mech), the controls contractor (Rapid-Con), and the electrical subcontractor (Best-Elec). In that meeting, Rapidcon and Best-Elec were told by the general contractor that they were “weeks behind schedule”, and needed to “pull out all the stops” in order to catch up with their work.
The first course of action for the control systems installation was the parking garage CO detection system. In order to catch up, Rapid-Con authorized Best-Elec to work overtime on weekdays and Saturdays. This in essence negated much of the cost saved in the redesigns. Nevertheless, it was obligatory, as the general contractor made it known that if the completion dates for the garage weren’t met, there was going to be “bigger problems”.
Of the 60 CO detectors ordered for the parking garage, only two boxes of 20 each ended up being delivered to the jobsite. Inexplicably the third box of 20 had vanished. As the missing box was being searched for, Rapid-Con put another 20 detectors on order, as there was no time to spare. The 20 additional detectors were received and delivered to the jobsite. Two days later, the missing box of 20 was found, at another jobsite altogether.
The CO detection system got installed, in time and barely under the deadline, however there was still the issue of having the system checked out and commissioned. Rapid-Con’s field technician hit the job at the eleventh hour, allegedly performed his checkout, and left the job. It was subsequently discovered, by none other than Sure-Mech, that the CO detectors were miswired by Best-Elec, however just a bit too late, as the technician charged to check and verify these systems went AWOL and could not be reached. Needless to say, the following day the general contractor doled out some serious justice.
Moving to the actual tower scope of work…there is a VAV air handler serving upwards of a dozen VAV and fan-powered boxes (FPBs) on the first three floors (spaces such as the lobby, main offices, maintenance offices, fitness center, club room, etc.). A number of issues presented themselves with regard to the FPBs. The first issue encountered was the observation that the FPBs were not furnished with control enclosures, even though the VAVs had them. Odd to say the least, Sure-Mech was informed, and subsequently provided enclosures to Rapid-Con, for installation by Best-Elec (change order number one!).
The second issue regarding the FPBs was found upon technical checkout of the equipment and controllers. For some reason, the control transformers shipped with the units were “troublesome”, for lack of a better term. Apparently, about half of the transformers were “DOA”, and the unit manufacturer could offer no better explanation than “musta been a bad batch”. The manufacturer had a box of replacement transformers delivered to the jobsite, for installation by Best-Elec (change order number two!).
The third, and perhaps the most flabbergasting FPB issue, as it was arguably the most avoidable, had to do with the FPB control valves. Sure-Mech Mechanical, in a haste to get their hands on the control valves, had asked Rapid-Con if they could purchase the valves locally themselves, rather than wait out the lead time on Rapid-Con’s order (which turned out to be an extra two days). Rapid-Con reluctantly agreed, and so it went that Sure-Mech visited a local controls supply house, purchased the valves, and installed them. It wasn’t until final commissioning of the FPBs that Rapid-Con, much to their dismay, discovered that the control valves that Sure-Mech purchased and installed, had no actuators! Of course there was a box of control valves with actuators sitting on site (those that Rapid-Con had originally purchased and had delivered directly to the jobsite), so Rapid-Con pulled the actuators off these control valves, and handed them over to Best-Elec Power & Control, for installation by Best-Elec (change order number three…?).
Other issues encountered throughout the course of the project include, but are not limited to, the following…the garage outside air intake dampers, part of the CO monitoring & ventilation system, ended up being recessed into the cinderblock walls and required external linkage kits…the VAV air handler mentioned above was installed with no exhaust plenum section…the chiller flow (paddle) switches ended up not working, thus necessitating differential pressure switches to be installed for proof-of-flow confirmation…the cooling tower came with a factory furnished level controller (for make-up water to the tower) which needed to be field-wired…the combination strobe/horn for the chiller room refrigerant leak detector was installed behind what was to be the future entrance door to the chiller room…and the list goes on and on and on…
While most of these issues were addressed and promptly rectified upon discovery, perhaps the single most frustrating scenario played out toward the very end of the project: affectionately referred to as The Lake Homes Thermostats Fiasco. In short, there are around a dozen residence units that are located on the ground level, overlooking the condominium’s private lake. Each of these living spaces is equipped with either one or two stand-alone, non-DDC controlled fan coil units. The manufacturer’s rep furnished the units for installation by Sure-Mech. The equipment shipped with thermostats packaged with the units. The manufacturer’s rep furnished a wiring diagram showing how to wire the thermostats to the units. Best-Elec was given the wiring diagram, and wired the systems in accordance with the diagrams. Rapid-Con’s technician was subsequently instructed to “check out” these stand-alone systems, making sure that the thermostats controlled the heating & cooling valves, and properly commanded the fans to run. The technician ended up spending an inordinate amount of time on this task, without being able to complete it. Turns out, the manufacturer’s rep provided thermostats that would not properly control the fan coil units. To describe why this was and how this was figured out would require more words than any of you would care to read, I’m sure. The long and the short of it is, this situation caused quite a stir, and was only remedied by the manufacturer’s rep shipping replacement thermostats, for installation by Best-Elec (change order number four!).
Tip of the Month: So it was a bad
job. Big deal. Bad jobs happen all the time. The key is that we are
supposed to learn from such bad experiences. So what is there to
learn from all of this?
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