Complete heat leaking - an interim solution

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Hey Chris F, I wondered if any DIYer would be curious about how to drain the HM30 compustion chamber.

*** WARNING - Not for the novice ***

Here was my situation and then I'll give my solution.

Situation - it is January 2008 in Ohio the HM30 started misbehaving. I removed the combustion fan motor and looked inside, discovering a combustion chamber full of water. In two weeks we were to leave for a month long vacation and leave our 21 yo college student son to fend for himself. The weather was below freezing and looked like it wasn't going to change; also, I had thought about replacing the HM30 but, at that time, had no solutions I thought were suitable or affordable for both hot water and space heating and could be installed before we left on vacation.

I played with the HM30 for a few days and discovered that the water leak was relatively slow (about a cup of water per day) and formulated a solution my son could live with. Basically, I put a hole through both the base of the aluminum combustion fan assembly and another hole through the flange of the combustion chamber. I then tapped the hole through the HM30 combustion chamber flange and installed a 3/8" bolt.

When complete and reassembled, the HM30 worked normally. Once a day I was able to turn off the system, remove the 3/8" bolt, stick in a piece of plastic hose and siphon the accumulated water, thus emptying the combustion chamber. Afterward, I would remove the siphon tube, reinstall the bolt, turn on the HM30 and it would work well again.

My son accomplished this task for the whole time we were out of town and for another month while I searched for a replacement. I decided to keep the AM30 and replace the HM30 with an AOS Vertex condensing, high recovery water heater and have been pleased to date.

I thought of this as an interim solution to allow me to keep the house warm and operational while I worked out the replacement details. This had the advantages of not having to pull the gas line, the ignitor, and the entire combustion fan assembly, and the combustion mixer chamber in order to remove the water from the combustion chamber.

DO NOT ATTEMPT UNLESS YOU ARE FULLY CONFIDENT WORKING AROUND NATURAL GAS, ELECTRICITY, AND WATER AND FULLY UNDERSTAND THE OPERATIONS OF THE HM30 SYSTEM!!!

That's my story, any Questions?

Best regards
JohnP