Filter Maintenance; Filter Replacement - Raypak 503A Installation & Operating Instructions Manual

6. Perform leakage test on gas valves. (See Fig. 46.)
7. Inspect and clean burner using shop air.
As Required
1. Recondition or replace low water cut-off device (if
equipped).
2. Check sediment trap and gas strainers.
3. Check flame failure detection system. (See "Post
Start-Up Check," page 46.)
4. Check igniter. (Resistance reading should be 40-
75 ohms at 77°F).
5. Check flame signal strength. (Flame signal should
be greater than 1 microampere as measured at
the 2 pins on the bottom of the PIM™).
6. Check firing rate control by checking the manifold
pressure. (See "Manifold Check" on page 46.)
7. Test safety/safety relief valves in accordance with
ASME Heater and Pressure Vessel Code
Section IV.

Filter Maintenance

NOTE: Use Raypak replacement filters, kit number
012553F (12"X12") for models 503A-1003A and kit
number 012552F (16"X16") for models 1253A-
2003A.
• Inspect quarterly
• Replace when tracking pressure exceeds -0.5 in.
WC at 100% fan speed, except for models 1003A,
1753A and 2003A, which need to be replaced
when tracking pressure exceeds -0.7 in. WC at
100% fan speed.

Filter Replacement

1. Remove the filter box cover by loosening and
removing the two wing nuts holding it in place.
Fig. 47: Remove the Air Filter Box Cover
2. Remove the filter by lifting it straight up and out of
the slot in the filter box.
Fig. 48: Remove the Air Filter
3. Reverse steps 1 and 2 to install the new filter. Use
Raypak replacement filters, kit number 012553F
(12"X12") for models 503A-1003A and kit number
012552F (16"X16") for models 1253A-2003A.
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