Greetings!
Like many, I had a rat infestation in my Pentair Mastertemp 400 heater. Turns out that the damage was minimal, some gnawed wires on the igniter and flue temp sensor, and they chewed through the blower orifice grate. I was able to get all those things fixed, and the heater now works. Because they ate through the orifice grate I was concerned they had nested in the combustion chamber, so I I opened it up it and (thankfully) found no evidence that the rats had been there.
When I cleaned out the heater and removed the combustion chamber, I found remnants of the insulation pad that goes between the combustion chamber and the bottom tray of the heater. This is Pentair P/N 42001-0074S, Lower Enclosure Insulation.
It’s a circular-ish piece of foil-backed insulation, and rather than buying the OEM part I intend to fabricate a replacement for this when I put the heater back together.
My question for the TFP mind trust is simple; do I install this part with the foil surface facing up or down? I would assume down to keep surface moisture from soaking the insulation, but I could make an argument for up, as well.
Thanks in advance for your help. The Mastertemp troubleshooting articles here made the job pretty simple. While I was in there, I installed the MK rat-proofing kit and put some mothballs inside to prevent future intrusions.
Kit
San Diego, Ca
Like many, I had a rat infestation in my Pentair Mastertemp 400 heater. Turns out that the damage was minimal, some gnawed wires on the igniter and flue temp sensor, and they chewed through the blower orifice grate. I was able to get all those things fixed, and the heater now works. Because they ate through the orifice grate I was concerned they had nested in the combustion chamber, so I I opened it up it and (thankfully) found no evidence that the rats had been there.
When I cleaned out the heater and removed the combustion chamber, I found remnants of the insulation pad that goes between the combustion chamber and the bottom tray of the heater. This is Pentair P/N 42001-0074S, Lower Enclosure Insulation.
It’s a circular-ish piece of foil-backed insulation, and rather than buying the OEM part I intend to fabricate a replacement for this when I put the heater back together.
My question for the TFP mind trust is simple; do I install this part with the foil surface facing up or down? I would assume down to keep surface moisture from soaking the insulation, but I could make an argument for up, as well.
Thanks in advance for your help. The Mastertemp troubleshooting articles here made the job pretty simple. While I was in there, I installed the MK rat-proofing kit and put some mothballs inside to prevent future intrusions.
Kit
San Diego, Ca
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