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Checklist for new gas boiler installation (oil -> gas)

In_New_England Member Posts: 130
Hi Experts,

I'm going to have a new boiler installed for our FHW and the oil equipment removed. I'm coming up with a checklist for the salient points to go over before and after the installation. What else can you think of? (Some of the points are very specific to my basement)

  1. Have the engineers describe their piping plan to me
  2. Verify the intake/exhaust go though siding and not foundation
  3. Verify the piping and boiler don't block off part of the basement
  4. Verify no cuts/holes will be made in central beam
  5. Verify the valves are easily accessible, so I can do maintenance (flushing) myself when needed
  6. Verify the path of the condensate line is reasonable
  1. Flush baseboard heating loop
  1. Program outdoor reset
  2. Oil tank removal certificate
  3. CO sensor
  4. Seal off old chimney vent


  • ScottSecor
    ScottSecor Member Posts: 863
    Most of the heating contractors I know (including myself) are not engineers. We happen to have one on staff, but he almost never gets involved with a simple residential oi to gas replacement boiler design. Who removes the existing (about to be abandoned) oil lines, filter and leftover oil from the lines? Is the condensate from the new unit going to drain by gravity or does it need to be pumped somewhere? Who's providing and installing the CO sensor? Does the new equipment hang on the wall or sit on the floor, if the latter is the basement prone to flooding? How are you going to make dhw? Will there be a new gas line run from the meter or is there and existing oversized gas line that can supply the required gas for the new boiler? Is there asbestos on the old piping or the old boiler, if so who removes it/them? What exactly is the heating specialist going to replace (this list could be one item and it could be a dozen items)? Who pulls the permits, who pays for them? Who waits for the inspectors to come for inspections?

    Hope this is a good starting point.
  • hot_rod
    hot_rod Member Posts: 22,342
    Exhaust all options to vent up, or thru the roof, instead of side wall.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • In_New_England
    In_New_England Member Posts: 130
    hot_rod said:

    Exhaust all options to vent up, or thru the roof, instead of side wall.

    Could you elaborate why please?
  • ScottSecor
    ScottSecor Member Posts: 863
    By venting through the roof or up the chimney you eliminate a few potential headaches.   No "ugly" exhaust blowing out the side of your house.  No concerns of exhaust coming through your open windows.   No chance of exhaust gases condensing and freezing on sidewalk or driveway.   In many cases, less likely to get "re-gasing" by allowing exhaust gas to accidentally enter fresh air opening.
  • Dave Carpentier
    Dave Carpentier Member Posts: 603
    Im doing an oil to gas boiler switchover this summer too.
    Among the list of things I have to do for "prep" is;
    -run a #6 ground wire from my main panel into the util room to be able to ground the new gas pipe (no gas at all here currently)
    -terminate a receptacle for the new boiler (the oiler is currently hardwired via bx, but the new gasser is a plug-in)
    -possibly run a length of 18/2 or such from the north face of the house for the ODR (apparently they should on the north side to avoid solar effects, but Im going to need like 60ft of run for that)(then again, this unit can optionally do its weather via it's wifi, so I might not bother with ODR hardware ?)
    -mount a sheet of plywood for hanging the boiler and nearby hardware (my pref)

    30+ yrs in telecom outside plant.
    Currently in building maintenance.