I'm doing a garage addition, and I specified heated floors for what will be a 3 stall garage and a ~250 foot addition to my house. The quote I got was within my expectations for the insulation, PEX, manifold, and the boiler. Then the HVAC company put an option in for a combi-boiler to do my domestic hot water as well. They sell Viessmann. I trust the HVAC company, so haven't looked at other manufacturers. This setup is tankless, as the boiler is rated to heat water fast enough for my domestic use. This setup is also propane, not a wood boiler, due to travel that i have to do for work. I hadn't thought of using a boiler for my domestic hot water before seeing that option. I suppose I could be talked into it, as my current hot water heater is about 15 years old, and will have to be replaced at some point. A web search says that they last an average of 8 years these days, so I guess I got my money's worth. Further, I've never cared for my hot water heater setup, as the exhaust goes straight up from the basement, through the insulated chase, right next to the stove pipe. I've never measured it, but it feels like I have a pretty good draft out of the hot water heater exhaust whenever the wood stove is going. That all being said, I've got no experience with either boilers or combi-boilers. Are they worth looking at for domestic hot water? Or will it just add a layer of complexity that I don't need? I like the idea of having one device in the basement that does both, but my experience is that a device that is meant to do multiple things isn't quite as good as a device made to do one thing. Any advice on the subject is welcome.
I don't have any experience with a combination boiler, heck, I had to look up what they were. Looking at this list of pros and cons, one issue would be if you lose one, you lose both. Some people that would be a real problem, others it would be more of an inconvenience. It seems strange that on the list would be if someone is taking a shower, that you can't have other hot water going too. I would think that it would depend on the sizing of the unit - but what the heck do I know (rhetorical question, pretty much nothing is the answer to that)
I'm not experienced with anything but tank water heaters, but from what I understand, this is a downside to all tankless water heaters. A tankless can make x amount of gallons of hot water per minute, and a shower uses x amount of gpm. In this case, my shower is 2gpm and the combi is 4gpm, so I'd be able to run 2 showers at once (in theory) but not more than that. The upside is that I'd be not heating and re-heating a 50 gallon tank of hot water to be ready for use on the few times that I need more than 4 gpm of hot water. The tank just gives me a surge capacity that I don't think I have too much use for right now, and I think I could add a tank down the road if I needed to. I don't think that losing one means losing both would affect me overly much, as I heat with wood anyways. It would just mean losing heat in the garage and the entrance to the house, which wouldn't be an emergency for me. That all being said, I just have web searches and a few conversations to rely on, so if anyone is runnign a setup like this, I'd love to hear your take on it.
I use a boiler for back up heat and domestic hot water. When it was installed electric was not an option lack of available breakers. I heat a super insulated 60 gallon hot water tank as a zone. With 3 boys 15O gallons HHO for heat and hot water October to April 100 gallons for hot water April to Oct Now I would install a electric heat pump water heater
Thanks for the input! I'd be propane... There is nat gas on the road, but I never looked into it, as it would be a ~300' service line, and I only use about 60% of a tank of propane a year. What are you heating your boiler with now? And why would electric be preferred in your case? Sent from my SM-N950U using Tapatalk
Yes. I live alone, and the wood stove runs all winter long. Propane furnace seldom runs, and I would guess most of the usage is DHW.
Sorry HHO is home heating oil. Just cost, the heat pump water heaters have, think of a reverse refrigerator motor on top, they are More expensive but many states have rebates on them because there’s Green!
335 last year with myself 3 women and 2 dogs. I swim in the estrogen ocean. We used more last year as my wife wanted basement laundry room set to 60* not 50* . I tried to explain to her in a poured concrete basement BUT I digress my Buderus boiler get cleaned every 3 years is never dirty and tests out at 89% efficient knock on wood ohh and 4 ish cord of wood is my woodstove
Ahh...gotcha, that's with the woodstove...I thought you meant that was what you used before you started with the stove.
Note to self. Read these on the computer, not the phone. Keeps me from answering questions not intended for me. Sorry about that.
OK, I'm getting more confused on this. I've been talking to two guys at work this week. They both did heated floors in their pole barns, and are very happy with the result. They used this, or some variant thereof, and basically did most of the work themselves. https://www.menards.com/main/plumbi...65-c-8519.htm?tid=3346614592273430312&ipos=16 It seems super easy; it's all installed on a panel, pre-plumbed, and all you do is mount the panel and make the connections for propane, electric, PEX to the manifold, etc. The HVAC folks quoted me $1,500 for PEX, manifolds, and install. (I'd do insulation) I didn't think that was a bad price and saved me the hassle of learning lessons the hard way. The hangup is the $10k boiler that the HVAC folks say that I need, or $15k boiler they say I need if I want to do hot water. $10k is a pretty big difference from $3.5k. I'm not afraid of an investment, but a web search says that boilers last ~15 years, and that sound like less of an investment, and more of a fixed cost to me. Like if I want heated floors in the garage, it's going to be a $15k replacement every 15 years, or $1k in equipment a year. That, and them saying that they did large pole barns with 50,000 BTU systems, and the HVAC folks think I need 85,000 BTU's for a garage much smaller than their pole barns. Stuck in decision indecision right now...
Combi boilers are very common over here and I’ve lived in a few houses with them. Not a big fan to be honest. One of the downsides that has already been mentioned is that most of them cannot serve 2 or more outlets satisfactorily. For this reason, they work best in smaller houses where generally, this isn’t a problem. Some of the other downsides are the lack of hot water AND heating if the boiler fails and they are not as efficient for heating; well at least over here because the output needed for hot water tends to far exceed that which is required for heating. This means that they can short cycle (even with modulating burners) in all but the coldest weather. If you want hot water from a gas boiler, I think an indirect cylinder which can be heated by the boiler would be a better option. You can also specify these with electric back up, should the boiler fail. Viessmann are rated fairly well here but parts are very expensive and can be difficult to obtain. However, wet heating systems are the norm here so there’s many other more mainstream brands to choose from. Hope this helps from someone in the UK commercial HVAC industry.
Is that the exact same model that they quoted for? It may very well be and I'm just throwing that question out there but the one pictured is only guaranteed for 3 years which seems very low to me. "It seems super easy; it's all installed on a panel, pre-plumbed, and all you do is mount the panel and make the connections for propane, electric, PEX to the manifold, etc." It may be super easy until unforeseen issues arise. Some questions to ask yourself: Does your town/state require inspections for installation of such equipment? How sure are you of working with lines that will be carrying gas? Are you on a timeline? That, and them saying that they did large pole barns with 50,000 BTU systems, and the HVAC folks think I need 85,000 BTU's for a garage much smaller than their pole barns. I thought the idea of the combi boiler is that it was going to service the DHW also? I don't think the boiler you linked to does that (I could be wrong). Also, just the boiler and the zone panel (assuming 3 zones) is about 4.5k. That doesn't include all the connections and electric set up. When I had my mini split system installed this past summer, the total bill was about twice what the piece parts would cost for the exact same models the proposals stated (the quotes listed everything - units/model #s, tubing, harnesses, cables, connections, covers for the cables on the outside of the house etc). Just some stuff for you to think about.
