Chromalox PN401 specifications INSTALLATION OF HEATER ASSEMBLY IN TANK cont’d

Models: PN401

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INSTALLATION OF HEATER ASSEMBLY IN TANK (cont’d.)

INSTALLATION OF HEATER ASSEMBLY IN TANK (cont’d.)

5.Begin lowering heater into tank as per Figure G, Step 1 thru 3 (end manhole) or Figure H, Step 4 thru 7 (center manhole). Once the heater has touched bottom, use pulling wire (front lifting cable) to pull heater toward far end of tank.

6.Before lowering back end of heater, visually gage the remaining length of heater to be laid down, to be certain an equal amount of clearance is allowed at both ends of tank. Back end of heater is lowered into place using rear lifting cable. CAUTION: NEVER USE RISERS TO SUPPORT HEATER TUBES.

7.Where additional heater assemblies are to be installed in the same manhole, follow same procedure, being careful not to interfere with risers or cable on the initial heater.

Step 1

Step 2

Step 3

Figure G – Tanks with Manholes Near End

NOTE: In tanks where the configuration does not allow following the above procedure, or in above ground tanks, ask for Factory rec- ommendations for installation of heater.

Step 4

Step 5

Step 6

Step 7

Figure H – Tanks with Center Manhole

INSTALLATION OF FXTH TERMINAL HOUSING

A.Position manhole cover adjacent to manhole. Very carefully untie rope from anchoring point and pass it through (1) manhole gasket,

(2)opening in manhole cover, and (3) terminal housing gasket. Securely refasten rope to anchoring point. Do not allow riser end(s) to fall into oil, or permanent damage will result to the heater. Bolt down manhole cover using a suitable gasket sealant if required to obtain water-tight seal.

B.Pull riser(s) upward into position next to terminal housing. Wrap teflon tape on threaded riser connections and fasten into underside of terminal housing. Unused connections on bottom of housing will already contain flush plugs. Attach lifting cables to ring on under side of terminal housing.

C.Bolt terminal housing to manhole cover or manhole cover adapter, again using suitable gasket cement. If manhole cover is machined per Figure B, be sure to install copper gasket washers under bolt heads. Position housing so conduit connections are in the most convenient position for your particular installation. Connect all riser leads to terminals, following markers on wires and terminals referring to wiring diagram Figure J.

D.Install power leads from terminal housing to control center. See Specifications Table, Page I for amperages to determine wire and conduit size as determined by the National Electric Code.

E.To install thermostat wells, insert closed end of the well into brass fitting in bottom of terminal housing. Push well completely to bottom of tank. A preliminary measurement from manhole level to tank bottom will aid proper insertion. The well may first hit the heater. It is then necessary to manipulate the well so that it will glance off the rounded heater surface and extend to tank bottom. Mark side of tube at the swage fitting and then pun upward sev- eral feet to working level. Using a tube cutter, cut the tube at a point exactly 7” below the mark. Once the tube is cut, be extreme- ly careful the tube is not allowed to drop through fitting and into tank. Partially tighten fitting so this cannot happen. Position the upper end of well 5” off top of tube fitting, then firmly tighten the fitting. Insert bushing (located in shipping bag inside of terminal housing) into top of well. This will prevent burrs on tube from cutting the bulb or capillary of thermostat. Repeat this procedure until all wells are installed. There can be as many as three wells;

(1) Thermostat, (2) Temperature Indicator, (3) Low Limit Alarm.

F.Install thermostat mounting plate. Make sure thermowells are aligned with openings in plate and over-temperature leads from riser are brought through plate. Fasten plate into position.

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Chromalox PN401 specifications INSTALLATION OF HEATER ASSEMBLY IN TANK cont’d, Installation Of Fxth Terminal Housing