Cambridge Air Solutions.
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M-Series Technical Manual
NOTE: Take care not to drill or screw into sump tank.
6. Check for air leakage. Air leakage will lower the efficiency.
7. Check that DEC is level for proper water transfer through system.
8. Check that the sump pump has a good seal to floor.
Roof Top Configuration – M-Series w/Evap Unit
E.V.I.
CURB BY OTHERS
(Min. Recommended Height: 24")
EVAP
SECTION
TRANSITION
MOUNTING RAILS
(BY OTHERS)
HANGING RODS
TO ROOF BY OTHERS
4-WAY
PLENUM
DISCHARGE DUCT
BY OTHERS
PITCH POCKETS
(BY OTHERS)
PLUMBING / FILL AND DRAIN VALVES:
1. All installation should be performed in accordance to local and state codes and with proper permits.
2. Make-up water connection is ½” FPT.
3. Install 3-way fill valve (if supplied by Cambridge) in a conditioned space to keep the pipe from freezing (see
attached schematic).
4. The 2-way drain valve (if supplied by Cambridge) can be installed outdoors or indoors under the roof line in a
frost-free environment. See schematic below. If the 2-way drain valve is installed outdoors (above the roof level),
valve cover(s) are required.
Auto Drain with Freeze Protection (Optional)
Install two-way drain valve (supplied by Cambridge Air Solutions, as an option, and installed by Contractor) on
the sump’s drain connection. Install three-way fill valve (supplied by Cambridge Air Solutions, as an option, and
installed by Contractor) under the roof-line with port “AB” piped to the make-up water connection from the sump.
Port “A” is piped to city water supply and port “B” is piped to an approved roof drain. (See attached drawing.)
During normal operation of the unit the drain valve will be shut and the fill valve is open from port ”A” to port “AB”
letting city water enter the sump. Water level is adjusted and controlled by a float assembly to a level ½” inch below
the overflow. On a freeze signal or a signal from 24-hour time clock, the drain valve will open allowing for the sump
to drain. Simultaneously, the fill valve will shut off the city water, closing port ”A” to port “AB” but will open port
“AB” to port “B,” thus allowing the remaining water in the exposed pipe from the valve to the sump to drain to keep
pipe from freezing. A low-water cut off switch will protect the pump(s) from running dry.
Relocate the freeze stat bulb (located inside the electric control panel) to the outside of the enclosure to ensure
correct temperature readings.
