Zero Zone RVZC30 Service Manual

Email not displaying correctly ? View it in your browser.

Zero Zone Electric Defrost Heater
Element Replacement

This tech bulletin describes how to replace electric defrost heater elements for Zero Zone Evolution
freezer cases built between 2005, when the product line was initially released, and later. From the
3rd quarter 2005 until the 1st quarter 2008, the defrost heaters in RVZC30 electric defrost cases
were built with two separate heaters, a front and a rear. After the 1st quarter 2008 the design
changed to a one-piece, U-shaped heater. The one-piece heater is the replacement for the original
two -piece heater.

Heater replacement procedure:

CAUTION – use extreme care to avoid injury from the sharp fins on the coil. Turn power off to

cases being serviced to avoid electrical shock and injury from rotating fan blades.

After the coil is exposed, unscrew the four cable clamps at the right end of the coil that hold the
elements to the case floor pan. Loosen the closure plates at each end of the coil (photo 1 and

photo 2), remove Fan Shroud ends (photo 1 and photo 2) and remove coil support brackets

(photo 3).

For orientation, the front leg of the element is located about 1” above the floor pan. The rear leg
of the element is located 2” above the floor pan on the original two-piece heaters, and 3” above
the floor pan on the later one-piece heater design (photo 6 ). Install the rear leg of the
replacement heater in the same location as the original heater.

With a permanent marker, mark the exact location of the retaining clips on the evaporator coil.
Remove the front heater by pulling the clip forward with pliers, working from left to right, until the
heater falls to the floor pan (photo 4). After the front element is free from the clips, again using
pliers and working from left to right, raise the clips until they are free of the coil (photo 5 ). The
rear element will come up with the clip.

Install the new one-piece, U-shaped element in the reverse order. Start with the rear leg of the
new element resting on the top of the coil. Place the retaining clips in the same position they were
originally located, and push the clips down using a block of wood to avoid injury from sharp coil
fins. Reconnect the new heater leads to the terminal block and brown-wire Klixon. Reseal wire
egresses at both ends of the case. If refrigerant lines are adjacent to the left end of the one-piece
replacement heater, install Zero Zone part 31-0133, Bracket Defrost Heater Retainer (photo 2).

Heater elements and heater clips are available through the Zero Zone parts department, call (262)
392-1300. The elements are coiled and shipped in a 27” X 30” X 2” cardboard package.

CASE

SIZE

2-Door 169-0177-02 169-0178-02

REPLACEMENT DEFROST HEATER KIT PART NUMBERS

6.5" COIL FIN DEPTH

1

7.5" COIL FIN DEPTH

3

2

3-Door 169-0177-03 169-0178-03

4-Door 169-0177-04 169-0178-04
5-Door 169-0177-05 169-0178-05

Back to Top

Photo 1 - Right End of Coil

Back to Top

Photo 2 - Left End of Coil