Questions and Answers - submitted 11-30-18.docx

Questions and Answers – Purchase and Installation of Air Handler Units for McFarland BidBuy Bid# 3946 Question 1 - Is it required to pre-air balance at the existing air handler units before replacement?

Answer 1 – Yes.

Question 2 - Is it required to air balance at the new air handler units after replacement?

Answer 2 – Yes.

Question 3 - Do the basement pumps need replaced?

Answer 3 – No. Those are not mentioned in the scope of services.

Question 4 - There are existing fire dampers and VAV reheats they are not to be replaced as this is a direct change out of the AHU that is the intent of this IFB correct?

Answer 4 – No – per Section 1.2.3.1 of the Invitation for Bid, “Variable air volume (VAV) control systems which will be installed into the ductwork in the mechanical room of each building to aide in maintaining zone temperatures”.

Question 5 - There is no work to be done on the existing primary loop (i.e. insulation repair, valves, or loop circulating pumps)?

Answer 5 – Existing primary loop work must include strainers for the chilled water and any modification to hook up the new unit to the existing piping and shall be insulated and have proper valves and pumps if not using existing valves and pumps.

Question 6 - Do the buildings require a pre-test and balance? And a final test and balance? If so, please provide a print with the existing grills and required CFM’S?

Answer 6 – Yes, a pre-test and balance will be required. Cubic feet per minute (CFM) is 14,585 and this is on the name plate and the blueprints.

Question 7 - Is ECSI (Environmental Control Solutions, Inc.) a proprietary control contractor?

Answer 7 – Yes.

Question 8 - Where is the stopping point for the demo of the piping and duct work?

Answer 8 – This installation should mimic the most recent upgrade of the air handler unit completed on Stevenson Hall building as shown during the walk-through.

Question 9 - The existing duct is lined so will it need to be cleaned? If so how far does this need to go?

Answer 9 – Existing duct may have to be resized for the newer unit as the current one is fifty (50) years old and there have been many changes to air handlers and duct work over the past few years. This was also shown during the walk-through of the Stevenson Hall building.

Question 10 - There is existing fire dampers in the mechanical room do these need to be tested for operation and documented or are these to be replaced?

Answer 10 – If the duct work line up and is operational to the fire damper(s) that would mean the existing dampers have already been tested.

Question 11 - Will the asbestos be removed from the piping and or duct by others?

Answer 11 - Asbestos on piping will be the Vendor’s responsibility to remove to the nearest fitting.

Question 12 - Will the new duct need to be insulated internally or externally? Please provide a spec.

Answer 12 – The duct work is to mimic the most recent upgrade of the air handler unit completed on Stevenson Hall building as shown during the walk-through.

Question 13 - What are the acceptable equipment Manufacturer’s?

Answer 13 – Per Section 1.2.3.2 of the Invitation for Bid, “The new air handlers for each building are to be equipped with variable frequency drives that use variable air volumes and that will work in unison with the direct digital controls (DDC) currently at the Center”.

Question 14 - Who will be providing the VFD’S? Electrical contractor or the HVAC/control contractor?

Answer 14 – That is considered part of this project and should be considered when submitting a bid.

Question 15 - What is the cubic feet per minute (CFM) requirements for the outdoor air?

Answer 15 – Approximately 15,000 CFM. The square footage of the unit will indicate the sizing needed for the outdoor air volume.

Question 16 - Will the outdoor air dampers need to be replaced?

Answer 16 – No.

Question 17 - Smoke detectors - please clarify if we are re use or provide new.

Answer 17 – Reuse.

Question 18 - What is the pressure classification for the new duct work?

Answer 18 – Constant static pressure. This should be calculated during sizing of the new units.

Question 19 - Do the reheat coils need to be replaced or cleaned?

Answer 19 – Replaced because it is part of the unit(s) being replaced. The new air handler units must include coils for both heating and cooling.

Question 20 - Do the reheat coil piping have to be replaced?

Answer 20 – More than likely there will be some modifications to the piping necessary.

Question 21 - Will 7:00am - 3:30pm work hours be acceptable?

Answer 21 – Yes.

Question 22 - Is the Using agency going to remove the asbestos wrap or is that to be done by the contractor? If it is to be done by the contractor what is the scope of the removal? Do we remove all the ACM or do we stop at the nearest fitting?

Answer 22 – Some possible asbestos removal will be the Vendor’s responsibility. It is to be removed from piping to the nearest fitting.

Question 23 - Is the sprinkler piping going to be moved buy the using agency or is it to be done by the contractor?

Answer 23 – If necessary, the Center will handle this.

Question 24 - What is the current max CFM of the existing equipment?

Answer 24 – Approximately 15,000 CFM.

Question 25 - Is there a print available that could be viewed as an as-built from a previous project that could be referenced?

Answer 25 – Yes. Contact the Center’s Chief Engineer to set up a time to view this.