Another GB142 victim

Joe

Hi folks,

Haven't been here for while but I'm back again with some questions and looking for thoughts on my GB142-24 I've had it since 2006 and it's had the same issues like most, including having the heat exchanger replaced. I had a good plumbing guy servicing it for a while, he lives about 2hrs away and used to come to my area to see his daughter so it worked out, but he doesn't come to the Boston area anymore even after I offered to pay for his travel time. Time is money right? So I've been cleaning it and replacing parts myself for the past few years and it's been going ok since all of the leaks basically rusted shut. I've cleaned the manifold piping up but that process seems to have allowed it to weep and rust shut again, so I've left that alone the past few years and it hadn't given me trouble until the other day when I saw the pressure was too high and drained some water to bring it down.

I must have done something wrong because it was giving an F7 error code which I looked up and it told me to replace the safety, supply and return sensors along with the circulation pump. This was at 2am Sunday night after the superbowl. I tried my best to get it back and running before throwing parts at it but by the time the local supplier opened at 7am I gave in and bought the parts. Took me a while and I replace the sensors and circulation pump (that was rough) as well as a new flame sensor and ignitor.

Long story short it continued to give me F7 and I ended up lowering the pump speed from 3 to 1 (the old one was on 3) and lowered the heat temp to 170 because it gave me an errors about going over the set temp. With it set to 170 my house is now the steadiest/warmest it's ever been, but the control panel is showing pressure around 36 and the manifold gauge is stays around 15 and doesn't really move. This is about the same as it was before I replaced the parts. I'm actually very happy with it now, but it's weeping a bit at the dialectic fittings, likely because I had a hard time getting the new pump in and must have disrupted the rust keeping it closed.

I don't want to mess with it as this point since it seems happy, but is the control panel and manifold pressures being that far off from each other normal? I replaced the pressure sensor a few years ago and I took it out and it was really clean but I did clean what little gunk there was. Could this be the culprit with pressure readings being so far off? Another clue to this is the pressure relief valve hasn't gone off at all even though the panel reading was over 45-50 when it was having issues, so this is making me this the actual pressure is what the manifold gauge is showing.

Lastly, I'm looking for thoughts on having someone (if I can get someone) replace the manifold and anything else that isn't right. One of my first servicing guys said the installer took a Ferrari and and turned it into a Pinto based on what he was seeing. I'm also considering replacing the whole thing and going with something from lochinvar or viessmann.

The house is an 1875 3-story Mansard roof that we gutted day 1 so it has insulation but it does have some air leaks though it's not drafty. The cast iron radiators were replaced with Haydon baseboards. I don't exactly have money to burn but want to get out of servicing this myself and looking for thoughts! Thanks in advance to anyone that reads this. Here are some pics.

Ironman

The pressure sensor was your only problem and it just needed cleaning or replacing. IDK why the manual would have called for the pump and sensors other than as SUGGESTED causes for the error code.