Pentair MiniMax 525 Operation & Installation Manual page 10

Maintenance (contd.)
For heavy soot accumulation which cannot be
successfully removed by merely brushing, the heat
exchanger must be removed from the heater.
1. Disconnect the plumbing at the flanges.
Remove the thermistor, hi-limit wires and
pressure switch tube from the inlet outlet heater.
CAUTION
When lifting the heat exchanger out of the fire box,
use caution so as not to damage the fire wall.
2. Remove the heat exchanger.
3. Place exchanger in an area that won't be affected
by chemicals or strong detergents.
4. After spraying the exchanger with water, use a
mixture of detergent and water. Pour, spray or
brush on.
5. Rinse the solution off of the tubes and inspect them,
repeat if necessary.
6. Alternate method, have exchanger sand blasted at a
local facility.
Reinstalling Heat Exchanger
1. Inspect fire box for damage or cracks that would
allow heat to leak out into the outer cabinet and
controls.
2. Remove any old sealant from fire box.
3. Apply new sealant to the fire box using a quality
industrial grade R.T.V. or equivalent. The sealant
must completely seal the space between the heat
exchanger and fire box, so that when the heater is
firing, heat does not escape to the outer cabinet.
P/N 470880
4. Place heat exchanger into the box and push
down firmly, until the heat exchanger sets
solidly on the fire box.
5. Reconnect the inlet and outlet flange to the headers
(use new flange gaskets), be careful not to move
the heat exchanger and break the seal.
6. Reinstall flue collector, inner panel and top.
Fire Box
Do not store combustible material, gasoline and
other flammable vapor and liquids in the vicinity
of this or any other appliance.
CAUTION
Rev. K 5-31-06
1 0
Heat
Exchanger
Flue
Collector