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Help with price estimate - Domestic coil replacement in steam boiler

Aveeight Member Posts: 29
edited March 2016 in Domestic Hot Water

I have a ~20 year old Weil Mclain steam boiler with summer/winter water hookup.

The hot water has been intermittently having problems, basically it won't fire up the furnace when you use the water. There is a lot of visible calcium build up outside the coil and a small amount on the mixing valve. I assume inside the coil there is a ton of build up, and it is blocking the probe that runs the thermostat.

I had my maintenance company come and they generally agreed. They sent a junior guy over and he basically said 'yup, that looks bad'. It might cost $500 to replace, but he admitted this was out of his area and needed to call for advice. They had a mid level guy come over (days later) and he said 'Yup, that is probably bad, but you also need to replace the mixing valve and and maybe this piece of copper piping which has some build up (unrelated to hot water but good to fix now)', he ballparked the work at $1000.

That seemed reasonable given the coil has to be $350 and the other parts are another $200. 4 hours of work and its around $1000 for sure. Their boss left me a voice mail with another estimate this morning saying he reviewed the notes and it is going to be $2800-$3000 to replace the coil, the mixer, and about 2 feet of 1.5" copper piping (bottom of steam boil, the return area).

That seems incredibly disproportionate to the amount of work. I plan on getting another company in to give me a second quote - but I know there are experts on here who can quickly tell me if I should be looking at $1000 or $3000 for this. The numbers seem so far off, and $3000 is way above anything I expected. Not looking for an exact price - just a general estimate to see if I am being taken advantage of here.

The boiler (even at 20 years old) is otherwise in great shape, supplies ample steam, heats up quickly, is very efficient and I have no complaints.

I can supply pictures if that is useful.


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    edited March 2016
    Pricing is not allowed on this site (it's in the rules). But you should get another estimate, it does seem high.
    However, there could be other things at play, including the difficulty of removing the coil (everything rusted, especially the bolts).
    Your wet return repair may not be as simple as cutting out some pipe and replacing it.
    Ask them if they can better explain their quote (they aren't going to break it down completely), the amount of time they think it will take.
    Let them know you need to compare their quote to the others you are seeking.

    There was an error rendering this rich post.

  • Aveeight
    Aveeight Member Posts: 29
    Thanks SteveUsaPA, I know pricing is not allowed and I don't want an exact number - just looking for orders of magnitude guesses. I have no basis for comparison and the numbers are so wildly different I am lost. I did call and ask for a detailed break down - that was a good idea. I suspect perhaps Hatterasguy is correct and they just don't want to do this, my feeling is they are trying to make the price seem so high that replacing the furnace is a better option (which is crazy).
  • vaporvac
    vaporvac Member Posts: 1,520
    could you just go with a separate HW heater?
    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239
    I personally am very careful approaching indirect coil replacement jobs. The worst is when they are leaking around the flange. A boiler with an indirect coil will stay hot in order to provide DHW year round. As it starts to leak, the water keeps evaporating and goes unoticed by the HO because they don't see a puddle on the floor Usually by the time it is noticed, the decay is rampant and the machined surface on the block is destroyed as well as the bolts thoroughly seized into the block and almost rusted off on the mating surface. That, my friend , is a game changer. What appears to be a simple repair can turn into a boiler replacement. It depends on the age and shape the boiler is in.

    What kind of leak do you have? Turn the boiler off and let it get cold. If you see water coming out once it gets cold, you have a bad one. If you have white/green buildup around the leaking area, you can be assured that the inside of the boiler is plastered with mineral buildup, greatly reducing the efficiency.

    Whenever I am working on a boiler, if I see any signs of leakage, I pull it apart and fix it right away. Doesn't have to have a wet surface or be dripping. If the signs are there, it's happening.