[nochaos]

Quite helpful

I do have a shutoff valve on the vertical supply line.

The total length of the piping that I described is just about 10 inches, if I recall it right (I am at the office now).
Within that I have the: Pipe--Coupler--Pipe--Assembly.
On the vertical (just outside the furnace enclosure) I have: Elbow--pipe--valve--pipe--reduction coupler/ adapter to supply copper line. The supply line goes up for about 5-6 feet.

I will surely have to hack saw the pipe at the location you mentioned, unscrew the coupler from the left hand side pipe, and replace the coupler and the sawed off pipe with new pipe + union.


Now, there is another bummer... I would not know what HSI model I have till I take it out! That means that by doing the above I will have to take out the assembly and the HSI, check out the HSI, replace the HSI and the assembly, connect the union and the pipe, run like that till I receive the new HSI, and redo the steps above. Double the work. Great...

Not to mention that in order to take out the burner assembly I have to unscrew like 4-6 screws. Antique design, with no clips of any kind. To top everything off - yes, the installer did a number on the old folks that I bought the house from 9 years ago... Or it looks like the number is on me now...

I would almost want to just replace the controller and see if that solves the problem... But then the HSI has 120 ohms and that likely means that it's worn off and has to be replaced. My biggest fear is not that I'd have to place a follow up order for the HSI, but that after replacing the controller the whole thing may be solved for a while, after which the whole shows will restart. That can happen if somehow the HSI resistance puts some sort of strain on the 120V/24V IGN to sensing switching cycle and the respective relay.

I suppose I better take the safest, yet not cheapest way of replacing both and be done with it..

Thanks.

Thanks,

Eugen