Peerless Coil Replacment

sbyrne

I have two oil fueled Peerless boilers in a two family for heat and domestic hot water. Both installed around 2006. The model is WBV-03-110-WPCTL. During the annual service call the tech said that I will need an indirect tank(s) for domestic hot water because the coils are shot. I replaced coils in 2019 in unit 1 and 2021 in unit 2. You can see where there is some rust on the outside - same for both boilers. The tech said I might be able to replace the coils if he can even find them. But doing so will damage the seals in the long run so an indirect tank is the best move. I think I trust this company but still wonder what my best move is short of total boiler replacements? Can I -should I - replace these coils or should I really look hard at the indirect tanks? In the Northeast US on city water if that matters and natural gas is not really an option. I’d really appreciate any advice on this because both boilers are a huge hit to the wallet.

ethicalpaul

I'm confused...is he recommending replacing the boilers?

My answer, always, for this is don't use boilers to heat your domestic hot water. In your case since you have no natural gas you might look at a couple heat pump water heaters. You won't have to buy indirect tanks, nor circulation pumps, nor should you have to replace your boilers (if that is what he is saying...I can't tell)

HVACNUT

It's not the coils that are "shot", it's the coil gaskets. And he should have noooo problems finding them. Should be a fairly easy fix, but time consuming. Looks like PP fittings. No way should it look like that after 4 years, or ever. The bolts need to be torqued at every annual maintenance. That's what seems to be happening here. It's also possible there's still some remaining old gasket still stuck to the cast iron block so it should be checked for smoothness when the coil is out.
Indirect water heaters are definitely more efficient than a tankless coil. But even if you go that route, the coil gaskets still need to be replaced. 

EBEBRATT-Ed

Agree with @HVACNUT
If the coils were bad and leaking it would overpressurize the boiler water (heating side). If thats not happening the coils are ok and not leaking. Remove the coils and replace the gaskets and retork. Clean all surfaces and use "neverseize " on the bolts.

ethicalpaul

Respectfully, I don't know how anyone can tell the coils aren't bad from here

EBEBRATT-Ed

@ethicalpaul The coils are only 2-4 years old. Tankless coils usually last a lot longer than that. Most coils get changed because the gasket leak because the torque on the bolts is not maintained. Then the gaskets leak and deteriorate.

I admit a tankless is not the best way to heat hot water but for a small family they can be ok. I can see spending thousands for a HPWH or a new boiler or indirect when he may only need a gasket bolts and some labor.

sbyrne

@ethicalpaul Thank you and everyone for the responses! The tech said I could replace the boilers. Of course that is always an option but least desirable. I don't think heat pumps are an option based on the venting requirements.

Mad Dog_2

Tankless coils are good for decades..As the boys said, the Gaskets dry rot.  They are cheap.  On all new coil installations, I use High Temp Grease on the 🔩 bolts, so they won't snap off 25 yrs from now.  Everyone doesn't HAVE extra money to Go Green always..That can be fixed for a fraction of the cost of a Heat Pump.  Mad Dog 🐕 

ethicalpaul

Venting requirements are minimal. If they can fit in the room with the boilers, that will be fine. Especially in the winter when the boilers are heating that space. It's not that a specific volume of air is required, it's really a combination of the amount of air at a certain temperature.

They just give a volume of air as a guideline, and that guideline is quite small, just 10'x10'x7' is all they ask for.

mattmia2

A gasket like that should last the better part of a century if it is engineered and installed properly so my question is did the person who installed it not use a torque wrench or are these not designed right? It likely should be re-torqued a couple times in the first couple years but after that it shouldn't compress anymore.

mattmia2

The leaking from the bolts only makes me think maybe they go in to the wet part of the boiler and didn't get sealer on them.

ScottSecor

We rarely install boilers with tankless coils these days. That being said, I have seen many coil plates leak within five years or so. Keep in mind that some of our more cost conscious customers used to turn the boiler off for a day or two in the summer, then turn it on to bathe for an hour or so.

We too always use "never get off your hands"... I mean never seize on the bolts, it certainly helps if you need to tighten or loosen them in the future.

mattmia2

ScottSecor said:

We rarely install boilers with tankless coils these days. That being said, I have seen many coil plates leak within five years or so. Keep in mind that some of our more cost conscious customers used to turn the boiler off for a day or two in the summer, then turn it on to bathe for an hour or so.

We too always use "never get off your hands"... I mean never seize on the bolts, it certainly helps if you need to tighten or loosen them in the future.

that is one of the few times i wear nitryl gloves

Mad Dog_2

Permatex is the worst...as careful as are....Mad Dog 🐕