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What to do just before X-mas New boiler

superdavesuperdave Posts: 140Member
edited December 2018 in Gas Heating
So I got a call out for a Baxi HT 380 not giving consistent hot water. They are new owners of house and they had others come out and look at boiler could not fix it. I was so worked up I didn't take photos. So Now hear is a list what I found wrong. House is just around 3,200' four zones of heating with a manifold system. They installed venting of boiler with 2 pipes and used a dryer vent kit for the intake air. Gas piping was done wright!! The DHW was done backwards they put the Baxi Valve kit on the hot water outlet. On the heating system they did not do Prim/second and the zone valves (Taco571) was installed backwards. Tested the incoming water reads 50F and hot was all over please 100 -130 on DHW so I changed out NTC sensor same thing. Did a full tune up cleaned out heat exchanger found expansion tank bad and 3 way out let valve was not closing all the way. Ran the setup on boiler same thing as before. Changed out the gas valve thinking it is not mod. up and down. SO STRATED TO TEST ON COMBUSTING HAPPEN TO SEE THAT THEY STILL HAD THE 120V JUMPER IN ON TT TYIED IN (THIS BOILER WAS MADE 2011 WEEK 28). So even I take off a year this boiler has been on for about 52,560 hours holding temp and a lot of time pumping with zones off!! The CO2 and Co was way out with old gas valve also was out to even get it close on CO2 the CO was on high fire reading 500PPM and low was about 35PPM. Most of the time I can get low to 8.4% CO2 and CO 12PPM or less and High 8.7% CO2 and CO about 80PPM or less.
I left and told owner I need to step away to re think what more I can do and I told him I was not leaving him High and dry so I didn't charge him for any parts at this time or labor. Does anyone think of anther way to skin this cat?? The only thing I can think of is installing boiler drains on both supply and return and flushing out main exchanger to help get he heat transferring better. Also the boiler on DHW would get up to 220F and shut down but the DHW would not stay steady. I am thinking that this exchanger is plugged up with bad water seeing that the 3 way valve was and I am thinking the tubes a twisted out of place that is why I can't get the CO2 and CO to be normal

Any thought would be nice I don't want to tell them they need a boiler just before X mass.



  • DZoroDZoro Posts: 723Member
    Sounds like you already have too much into the broken mess. Can you seriously say that without a complete piping rip out and boiler that you would be comfortable with the system when leaving? There's so much wrong, doesn't sound like your patient would even survive complete surgery.
    My vote would probably be new. I have a feeling other contractors also told them replace...
  • superdavesuperdave Posts: 140Member
  • superdavesuperdave Posts: 140Member
    I know Just not what I want to tell someone before Xmas that the new house they bought needs new system. Any one else think if I flush out unit it would work??
  • DZoroDZoro Posts: 723Member
    Did you clean the burner side, and the domestic side? If so how did the burner side look?
    What bothers me is with a new valve and clean H/E you should be able to get good combustion numbers.
    Being you can't get good #'s, then you will probably be throwing more $ at it with blowers, boards......
  • superdavesuperdave Posts: 140Member
    I did clean out heat exchanger on combustion side with a spray foam cleaner and a soft brush to get in between tubes and flushed out with water all around heat exchanger and checked with paper towels. I didn't flush out heat exchanger on the wet side. I know that might help get the heat transfer better but do you think it would help on the combustion side??

  • DZoroDZoro Posts: 723Member
    Unfortunately not,
    how long is the venting? Removing the dryer vent pipe on the intake make any difference. I'm not really familiar with that unit, is the intake direct piped to the fan/venturi ?
    What did the combustion chamber look like, soot, burnt yellow/browns?
    Was the O2 almost matching your CO2?
    With that thing running like that really took a beating on its lifespan...…
  • kcoppkcopp Posts: 3,324Member
    I understand. I had to do the same w/ a Munchkin contender yesterday.
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