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Replacing old electric resistive with Condensing Gas Boiler or Ductless Heat Pumps

jrcolmena
jrcolmena Member Posts: 5
edited May 2021 in THE MAIN WALL
Hi all, there are similar discussions around here on this subject, but few of them in cold weather and many lack specifics, so I'll give you as much info as I can

Is an old 1930's house in the Berkshire Mountains of Massachussets (cold!) that I just purchased, the inspector did note that insulation had been improved and Massave had conducted an audit in the past, windows are double pane. Currently it has electric resistive baseboards. The house is small, 1060 sq ft, two floors, two bedrooms+1 bath on the second floor, dining/kitchen/living on the first. I have currently two options:

option 1) Mitsubishi HyperHeat 30,000 BTU outside unit, 12k on the first floor on one head and one head of 6k on each of the bedrooms. Quoted (PRICE REMOVED). Would keep my current electric water heater and replace in a year or two as well as the old resistors as a backup

option 2) Viessmann combi 95% AFUE boiler + water heater combo. There are no radiators in the house so all the plumbing will have to be installed, it was quoted with panel radiators (I prefer those to baseboard) (PRICE REMOVED). There is natural gas on the street so no cost to hook up to the natural gas utility. If I go this way I might install a two zone mini-split heat pump/AC in a year or two anyway for cooling and shoulder season.

I did some back of the envelope calculations, I was told electric bill for the house is around 400$/month on winters by our utility, I assume natural gas will cut it to a third of that and heat pumps to half of that, based on this math and Massave rebates the boiler pays for itself in 12 years, the heat pumps in 7.6.

Any comments? suggestions? I'm thorn, I don't mind paying up more upfront if it pays for itself in the long run, after all I bought a fixer upper. Also someone might say my back of the envelope math is bonkers. Economy is more important than comfort for me, as long as the systems are reliable since I don't want to deal with frozen pipes. I also wonder about resale value

Thank you in Advance!

EDIT: prices were removed, apparently is against the rules and I did not figure it out, I will say that the boiler system was almost double the heat pumps

Comments

  • kcopp
    kcopp Member Posts: 4,419
    edited May 2021
    NO Prices please ... please remove them. Its in the rules.
    jrcolmenaErin Holohan Haskell
  • kcopp
    kcopp Member Posts: 4,419
    If you wish to just satisfy a thermostat a ductless set up will do.
    I honestly feel a hydronic system hands down is a more comfortable system.
    Less drafts and no air blowing around the rooms.
    Panel radiation of cast iron radiators would be a nice option. Hot water baseboard less so but still better than an air system.
    What have they said the design water temperature is set for? The lower the better.....
  • jrcolmena
    jrcolmena Member Posts: 5
    @kcopp the proposal does not say, I will ask, but based on the model, Viessmann combi B1KA125 21-125 DHW149, I found these two temperature ratings on the literature:
    Boiler water temperature maximum 176 ˚F
    Adjustable high limit (AHL) range space heating (steady state) 86-176 ˚F
    And I removed the prices per the rules, apologies for that.
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,823
    @jrcolmena
    Try pricing out a ducted system - if you have basement access, could be easy to at least get the first floor covered by that. I'd expect your heat pump option to save more than half of the electric baseboard's energy use - the newest cold climate 30k Btu ducted Mitsubishi has a COP of about 4 at 0 degrees at 19k Btu output.
    A heat loss will be really helpful here: if you can, try to find out how many kwhs the house has used the past year or two.
    Comfort wise, the Mitsubishis are near silent and can use such a low fan speed you won't feel drafts unless you seek them out. They provide cooling of course.
    Resale value is anyone's guess, I'd be skeptical of any claims there.
    Ignoring the cooling aspect, $400/ month in the winter includes all electricity use and probably monthly fees, so keeping some baseboard will probably be the most economical option.
    jrcolmena
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    I would not rely on heat pumps where you live, unless you keep the electric baseboard as stage 2
    jrcolmena
  • kcopp
    kcopp Member Posts: 4,419
    The lower you can get the boiler design temps the more efficient the system will be... I would ask...
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,823
    Probably worth knowing total $/kwh and total $/therm too
  • jrcolmena
    jrcolmena Member Posts: 5

    Probably worth knowing total $/kwh and total $/therm too

    Im trying to figure out from the bill in my current apartment, my last bill was 70$ for 121 kWh so that makes .58$ per kWh which is insane, but that includes distribution and a bunch of fees, generation charges in theory are only 0.11 $/kWh

    For gas there are two rates on the utility website and I'm not sure which one would be me:
    R-1: Residential/ Non-Heating $0.9287 per therm
    R-3: Residential Heating, $0.4897 per therm
    R2 is low income so that is not me, logic would say R3 is me because is for heating, but with this utility rules you never know (both rates also include a $11.42 service charge)

    Again I'm new to all of this so I might be missing something
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,823
    @jrcolmena what's the name of the utility?
    Wanting AC tilts this decision in favor of the heat pumps, another consideration is the range. Do you want a gas stove or would an induction work? If induction works, avoiding a $144/year gas connection fee pays for the range.
  • jrcolmena
    jrcolmena Member Posts: 5

    @jrcolmena what's the name of the utility?
    Wanting AC tilts this decision in favor of the heat pumps, another consideration is the range. Do you want a gas stove or would an induction work? If induction works, avoiding a $144/year gas connection fee pays for the range.

    The Utilities are Eversource (Western Mass) and Berkshire gas. I think I would prefer the Gas but it is not a deal breaker, I'm not much of a cook anyway. The AC factor does play a role, at least no one has said "stay away from heat pumps in your cold weather!" Juse like @EBEBRATT-Ed said I have to keep the resistors as back up. So the economy seems to be tending towards heat pumps, even if Comfort is going for gas.
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,823
    edited May 2021
    @jrcolmena yeah no worries about that, heat pumps can work for colder places than yours. In many situations, the heat pumps for shoulder seasons is outdated - they're cheaper year round and the comfort isn't compromised. Plus you'll have backup. As cold as your climate is, it's promising resistance heat was only $400/month in the winter including DHW and all other electrical loads. Historical usage would be awesome to have. Do you have a roof or yard compatible with solar? If you lease it through a PPA or similar, you could get it for no upfront cost and save money from day one.
    ethicalpaul
  • Canucker
    Canucker Member Posts: 722
    edited May 2021
    @Hot_water_fan I'm going to take issue with the "comfort isn't compromised" portion of the statement. If you mean it will maintain your temperature setting, you're right. Comfort is subjective and it would absolutely compromise mine due to it blowing air around, making noise. I don't mind cold air blowing on me but I want absolute silence from my heat emitter. Heat pumps can't do that. To some, it matters more than dollars
    You can have it good, fast or cheap. Pick two
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,823
    edited May 2021
    @Canucker I think it depends on installer ability/equipment quality, as with most things. I've experienced godawful loud forced air (one with a hydro coil and another with furnace) and I've experienced silent, low velocity air coming from modern heat pumps. The variable speed ECM blowers are a game changer, I wouldn't recommend a single speed 1200 CFM blower. I've also experienced loud radiators too.
  • jrcolmena
    jrcolmena Member Posts: 5
    Based on your comments I'm gearing towards the heat pumps (ductless for economy of installation) I looked up the specs and even at 17 F the COP is 2.6, in this area we'll have only 3-4 weeks with lows below 17, and they still heat albeit ineficiently at -5, last year we did not get there even once, so I doubt we'll ever have more than 2 weeks at those levels, and in any case I have the back up. Thank you all