Homeowner advice on replacing boiler/hot water tank

Tim G

My wife and I just purchased a 1914 brick home in River Forest, IL. It has radiator heat throughout, an early 70s Weil McLain boiler, an a hot water heater 20+ years old (i believe). I'm planning to replace both with a new boiler and an indirect water tank. I'm also interested in the future option to tie in solar thermal. I've received two contractor bids so far (waiting on a third). The bids have different boiler and tank options. I indicated to the contractors that I am interested in as high efficiency as I can reasonably afford. We plan to be i the house for 10-20 years and so expect/hope the fuel cost savings will offset the higher cost.

The first contractor recommended a Vitodens 200 WB2832 and the Viessmann hot water tank EV153 (also gave the option of EVB79 for use with solar)

Second contractor recommended a Prestige Solo 175K BTU and 50 gal Vaughn stone lined indirect water heater. As a lower cost option he recommended a Quietside 90% 150K BTU, 80 gal American storage tank, Grundfos bronze pump.

Any thoughts?

There seem to be so many boiler choices, all pretty good and that you each contractor has the ones they are experienced and familiar with and so recommend those, yes?

Rich L.

Installs

Hi Tim, I install what is available and supported locally. I know I can get parts readily and if there is an issue after the install my supplier stands behing me as well. I've personally installed the Prestige and it's a great boiler. I've heard others speak very highly of Viessman products. I don't think you'll go wrong with either.

If you're looking at solar for a future upgrade go with an indirect tank that has two heat exchangers. With radiators solar would not give you a lot of help with heating your house, you just won't see high enough temps when you need them, but would likely benefit heating your domestic water.

Tim G

great info. Thanks!

jp_2

no insulation?

or is the house real big? I might looking into insulating the house as good as is reasonable, then recheck the heatloss and maybe go with smaller boilers?

also I would look real close at your real hot water usage?

I grew up in a house of 5 with a standard 40 gal.

mark ransley

I just got gas for 2.59 at North an Lathrop before getting a combo a Johnnys. You will need a written load calculation to know size realy needed, Most all were oversized here and its all to common still, especialy if any upgrades have been done to save energy you can save on cost and get better performance with the right unit. Here they usualy size your boiler by your wallet size. You need more bids, is that Viesmann a High efficency condensing unit?. You really dont need 80 gallon of HW, im not in the heat business but know a few installers. Research boilers at www.energystar.gov to see how efficent these units are are and what is for sale. There are options to save you on utilities but they cost, an 80 gal water tank is not efficent.

mark ransley

I tried looking up the Viessmann model at their site but I only found an 84% 200 series, remember your Weil is most likely 82% efficent now and boilers last a long time, a 70s boiler is not old. Unless you go condensing and understand limitations you wont save any money on utilities. The condensing I have read about are high efficency at under around 130f, heat over a certain point and efficency drops dramaticly. If you have the old cast iron radiators it will work now but when it gets real cold I need upwards of 170-180f, so your radiators play an important part in what efficency you will actualy get, these HE condensing units are perfect for radiant tube, they might work on radiators if you can get enought heat at a 130 water temp setting, I think some baseboard heat radiators need alot more than cast upright radiators. I think you will have a hard time finding a pro that gives you all the truth on what to do, so you need to do alot of reading. One test I am going to do maybe today is set my Aquatat to 130f and see how it heats the home, I know my pump wil run more when its cold but then I will get an idea if I can accept a condensing boiler. Another good idea is pull a permit, you get a free inspection, and you only pay after the citys free inspection, there are alot of hacks here in OPRF, even my favorite boiler guy screwed up one of my instals.

tim smith

Both boilers a good choice, I prefer the Triangle tube boiler

due to $$ and simplicity and not quite as much proprietary material required. Just my .02 worth. You might look at the Heat transfer products Superstore indirect water heater with 2 coils as one coil would be for future solar. Nice stainless tank. Tim

Tim G

I am doing quite a bit of insulating, sealing, etc. I had a home energy assessment/audit done. It makes total sense that the contractors might oversize what I really need, yet I hadn't been thinking about that much. They seldom get a complaint for oversizing a system, but obviously could if it is at all borderline meeting house heating, hot water needs. I'd much prefer saving money and energy by working with a smaller boiler and tank. I'll make sure the contractors are considering the insulating upgrades I'm doing.

D107

not sure if an energy audit

is the same thing as heat loss. HO here who's learned alot at this site. Most of the opinions I've seen here on this subject indicate that if your contractors did not do a proper heat loss--measuring every room, calculating in cold walls, cold floors, ceilings, infiltration factors etc. then it's guesswork. Many find that even the heat loss programs have too big a margin of safety and tend to oversize.

As for hot water needs, it is often recommended that you size for the heat loss and then get a large enough tank to handle the water needs. In many houses the HW btu needs are greater than the heat loss, which is solved by the larger tank.

I have a boiler 3.5x required size. Had a blower test, insulated walls; when I insulate the attic with foam, I'll do a new heat loss and get a boiler the right size. Already I've reduced fuel usage 35% and hopefully can eliminate another 35% in the future.

David

mark ransley

A load calculation is not an audit unless it specifies btu needed. I had 110000 btu, put in a 47-74000 2 stage furnace, then insulated, then had a load calc done and found I needed only near 40,000 btu. Unless you getthe load calculation in writing it has not been done. Heating companies here dont often do them even when asked. [I think everywhere]. If you have insulated their guesstimate of what you need is not correct, they just "wallet" sized ya. Smaller heating units cost less, pay for a real load calc.

John L

New boiler

We are Chicago based, 70 yrs in biz. Do heat loads.Contact me offline
John L

Rich Kontny_3

Both Good

I am a Triangle fan and go along with the tech support and parts availability factors. I would not waste a lot of time at this time on solar as it has marginal payback. Even with tax credits I would leave that option on the table and maybe put some valves and piping in but would look into a heat exchanger that stands alone with the future solar (if cost effective)

If you live in northern Illinois I would not even consider solar as a cost-effective system. I look at installation costs, maintenance and fuel savings.You do want to install the most fuel efficent boiler though as that is money well spent!

Rich Kontny

Charlie from wmass

Tim do a heat loss for the house as it is now and also check the radiators for what they can produce. You may find they will not require as hot of water as 180 for the cold months. Also you are talking free standing column radiators and not baseboard? COndensing boilers that are set up with outdoor resets save a lot of fuel in the "betweens" when the system does not require such hot water to warm the home. Also many new boilers are being sized more for domestic hot water production than for heat loads as everyone thinks they need 80 to 100 gallon indirect water heaters, I have commited this sin when indirects were new to me. Often this is not the case but you know what you use best. I tend to install 40 or max of 50 gallon heaters unless the people own a hot tub. As for solar, in Chicago photo voltaic may be a better choice than hot water production, but if you are sure you want solar then I would lean to the Viessmann as they also make solar equipment and they are made to go together with factory direct parts.

Tim G

Great info/advice. I'm leaning strongly towards the Prestige Solo based on what I've read and heard. I agree that a 50 gal tank is sufficient. I'll be checking on how/if the contractors calculated the heat load. Both in terms of cost, payback, and clearly need to do more research, I'll be shelving solar thermal for now. And yes, insulate, insulate, seal, caulk, foam.