A new thermal expansion tank with an 8.9-gallon acceptance voiume shall be provided (Similar to
Amtrol ST-30VC)} on the cold-water feed side of the boiler before the check valve. A new 2-inch
discharge thermostatic mixing valve shall be installed rated for ASSE 1017.
A new self-sensing ECM hot water recirculation pump (Similar to the Taco 00e) shall be provided
and installed to maintain hot water distribution temperature. The pump shall run whenever the
hot water return line reaches a temperature of 105°F or lower.
Contractor to provide all required valves, safeties and associated appurtenances for a complete and
operational system. Contractor shall provide startup services and training on site for the new
system.
Refer to attached specifications for equipment and materials information.
* Envelope Work
The contractor shail be responsible to fill/patch any existing holes in the exterior envelope found
allowing for infiltration to the return air plenum within the building. During survey of the return
air plenum it was noted that daylight could be observed in a number of areas at the exterior wail.
All such holes shall be closed to prevent cold air infiltration into the occupied spaces.
“ Electrical Work
The prime contractor (mechanical contractor) is responsible for retaining a licensed electrical sub-
contractor to perform power and wiring scope as per State Codes and the current edition of NEC.
E.C. shall provide all conduit, conductors, supports hangers, junction boxes, etc. for a complete
installed electrical system for the following noted equipment. E.C. shall power ACCU-1 shall be feed
from PPB-A located in the basement level. ACCU-2 shall be feed from PPB-B located in the basement
level. E.C. shall field verify exact location of existing circuit breakers as required. Information noted
was taken from electrical As-Built set from 1998 by Lengchamps Electric.
Provide the following:
ACCU-1 - (1) 80A/3P CB with 3#3,1#8G-1"C from unit to PPB-A.
ACCU-2 - (1) 110A/3P CB with 3#1,1#8G-1 1/4’C from unit to PPB-B.
Provide all required demolition of existing conductors, conduit, disconnect switches are required
for removal of existing units. E.C. may use existing conduit if sized properly for new equipment E.C.
shall field coordinate manufacturer type for circuit breaker compatibility. Mechanical units CRAC-
1A and CRAC-1B shall be interlocked so that only one can operate at a time.
The E.C. shall disconnect and make safe, units HVAC-1 and HVAC-2 prior to HVAC contractor
starting refurbishing work noted above. Once refurbish work is complete, E.C. shall reconnect units
as required. E.C. shall coordinate all associated work with HVAC contractor prior to start of work.
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66 Jackson St, Littleton, NH 03561 | 40 So. River Rd #35, Bedford, NH O3110 | Ph: 603.444.6578 | www-.yeaionessuviales.com
