Energy Management Estimating

[Mr. Wizard]

I have a 10 story building I am about to bid on (energy managment), and wanted to run some numbers by you guys and maybe you could tell me what you think

The building has 11 AHU's, and each AHU has a HWV, a CHWV, a DAT, Stop Start, Status, Outside Air damper, Freezestat, Smoke Detector, Mixed Air Temp
118 VAV's
16 Exhaust Fans
4 RTU's
1 Remote Chiller Yard
1 Split Unit (DX)
1 Boiler
1 HWP
1 CHWP

I'm thinking in the neighborhood of $47,000, but was curious about what some of ya'll think. The building is going to be retrofit, so the only conduit that needs to be installed is at each AHU (approx. 80' per unit). Thanks!

 

[Sysint]

I think you get buried if you aren't careful. Have you done this in the past?

For instance how much did you figure to hook up a VAV? Do you know what it takes to do it? I am thinking maybe not, because you didn't specify reheat, SA temp, communication, and type of room sensor.

 

[Mr. Wizard]

I have around seven years experience doing HVAC control work, but now I primarily do process controls. They're both areas of control work, same in a lot of regards, but different in many others. My problem is I don't have a whole lot of experience in bidding HVAC controls. I figured approx. $200 per VAV, there are no reheat coils, and each AHU uses differential pressure for status monitoring. I used the term DAT (discharge air temp), which is the same as a SA temp. The room sensors are local to each VAV, and there is also CO2 monitoring. I am trying to use unit pricing ($200 per VAV, $350 per RTU, etc...), but am a little (lot) unsure about my pricing. I have a couple of weeks to turn my numbers in, and any help is greatly appreciated. I can give as much info as needed for you guys help.

 

[Sysint]

From an integration standpoint I always figured 2 hours labor per VAV.
Typical AHU rooms and boiler plants I was typically around 40 hours. However, since I was a system integrator probably I have some different criteria. Anyway, there is always EMT to flex connectors and boxes to pick up various sensors in odd locations that always seem to take longer than normal. Regarding the split system - if it is larger tonnage you need to find out where the solenoid valves go, where they are interlocked and the voltage.

Hopefully you have all the points lists. If not, be sure to get them to be sure. 80' of conduit for an AHU in a room doesn't seem right if it has htg and clg valves, SA/RA/MA/OA temp sensors, SP, maybe a VFD, freeze protection and dampers.... all typical for an AHU. Who mounts the hardware? Is it up to you to setup an actuator on a valve or damper?

Who handles the comm wire? Is it LON or RS485 based? Definitely if it's RS485 there is extra time to make sure wiring in OK.

 

[Brian J.]

Wow! I wished I would've seen this post a lot sooner. I wouldn't even do the 118 VAV's for that price, but I'm in California, and our labor is probably quite higher. If you have questions about pricing this type of work, send me a PM. Best of luck, you probably got the job.

 

[stevenj76]

My gut says $305k. I'd like to know the answer now please. This includes the 120v.

 

[Brian J.]

Using a quick 10 minute take-off. I'd say around $200,000+ (no conduit, save for mechanical rooms, within walls, and outdoors.) And being that this is a remodel and 10 floors, it could be more. I did not factor 120 volts.