Looking to do away with my oil heat

[Timber12vt]

Hello all, I was looking up information on Air Source Heat Pumps/Ductless minisplits, anyways, I’m hoping to get some information/advice as the best way to cut WAY down on my oil heat, so bear with me as this might get a little long.
First off, we live in Topsfield, MA (not Maine or Vermont cold, but this winter has been tough), there is no natural gas near us, kitchen stove is propane, and the house is a cape (built in 1962), with two large occupied bedrooms upstairs on the second floor, the main living area consists of a large living room, small kitchen/dining room, and two back rooms (office and guest bedroom), an unheated sunroom (with 3 huge old patio sliders off of the kitchen) and a partially finished (unheated) basement. The oil boiler (about 6 years old) is in good shape, runs at about 82% efficiency, and heats our really old Hot Water Baseboards decently, except for the upstairs units. The problem I am having is that there is only one thermostat (near the living room) and the upstairs rooms (our master bedroom and our daughter’s room) are always about 5-10 degrees colder than downstairs, I think because the thermostat is satisfied too soon. We just had a Mass Save energy audit and the house isn’t in that bad shape, insulation wise, we have to change out a few windows, do some air sealing and add little insulation in the roof/crawlspace.
So I have a couple issues I would like to solve….and am looking for some help from this site to steer me in the right direction.
1.First off we are going to do the insulation, weather stripping, and air sealing Mass Save suggested
2.Have a Harman Accentra insert on order for the living room which will heat most of the main floor
3.I am thinking of buying a (4) zone mini split system, with one condenser mounted in the back of the house, and with a head unit in each bedroom upstairs, one in the basement and one in the sunroom to provide heat to those areas, with maybe adding a solar array to help defray the electricity costs, bonus is we will have A/C during the summer
4.I would like opinions on what to use for hot water (efficient & sufficient amount) as right now our hot water comes right off of the boiler?
-On demand water heater?
-Indirect water heater off of the boiler, even though I’m hoping to cut the boiler usage WAY down
-propane or electric standalone water heater?
Looking forward to hearing your opinions, ideas on how to reduce, and maybe eliminate for the most part out oil usage. Thanks so much!!

 

[chken]

• what did Mass Save say about your three sliders? Old sliders tend to be extremely leaky.
• 4zone mini split sounds good. I was wondering if the head unit for the sunroom was better than for the main living area? In summer, sunrooms are typically naturally vented, and in winter, you might be better off putting a thermal curtain to block off that area, so you won't have to waste energy heating it? Does it face south?
• a hot water heat pump is the way to go. Some here have had good luck with buying Geyser or Nyles heat pumps off CL to use with an existing hot water tank, while I and others have had good luck with the GE Geospring heat pump hot water heater that you can get at Lowes. I bought mine a year and a half ago, and I'm pretty sure that at the time the Mass utilities offered a credit that drove the price for the GE down to zero. I sent an email to a Mass friend to let him know. The payback is zero years to 2 years for most, depending upon what rebates your state offers. It's really a no-brainer.

 

[peakbagger]

With regards to the mini splits, the efficiency of the multihead units are far lower than the single head units. I don't know the technical reason why this is but unless its changed recently, single zone is the way to go. Mini splits are great but they are still electric heaters albeit 2.5 to 3 times more efficient. Mass is making some pretty dangerous moves that may raise their power rates substantially so you have to factor in potentially higher electrical cost but its doubtful that you will get to the point where its more expensive than oil. Utilities factor in on savings with minisplits that folks will zone the house and only heat the areas where they are currently occupying. This may work with some folks but a trade off with a minisplit is they aren't that good at recovering the temp in a cold room. I have found with mine this winter that if its cold out, I need to leave it at a reasonable set point 24 hours per day rather than setting it back. Thus someone used to having all rooms warm lose some of the efficiency gains.

For hot water, too bad you couldn't buy a Nyletherm remote HPHW htr and mount that near the Harmon. I think keeping the oil boiler with an indirect heater is bad option. I assume the boiler is cold start type unit and therefore its best to just leave it off until you need it. Probably a small fast recovery electric hot water heater is your best bet unless you want a Nyle humming away in a corner of the living room

Keep in mind that an oil boiler does serve to keep your basement and your floors warm. When I am running off the mini split, may basement does cool down and its noticeable that my floors are cooler. Once I run up the wood boiler that heats it up for a few days but it is something to factor in.

Installing an additional hot water baseboard zone isn't that hard if you can get to the pipes. With an insert, the cold second floor could get worse unless the heat gets upstairs and that isn't as easy as you would think. The thermostat on the main floor will be warmed by the insert. By the way nothing wrong with old baseboard, it really hasn't changed for many years unless its full of dog fur.

PV is usually a good idea in Mass but it depends on what incentives and how your utility runs its net metering program. Some utilities make you net out once a year usually in January, that is bad as it means that you cant build up a big credit in the summer and heat all winter with the credit as they net you out in January. Other parts of Mass has Feed in Tariffs, you get paid a premium for every KW you generate and then buy back power at the normal rate. Sweet deal if you can get it. Of course unless you have a south facing roof with no shading, it may not make sense. Spend some time figuring out what incentives and rate plans apply to you
(broken link removed to http://www.dsireusa.org/incentives/index.cfm?re=0&ee=0&spv=0&st=0&srp=1&state=MA).

By the way don't plan on running the mini splits off the power you generate in the winter, it really works best with net metering where you build up a surplus all summer an burn it up in the winter.

 

[BoilerMan]

VERY WELL SAID! ^^^^^^^^^^^^^^^^^^^^^^^^^^

As a refrigeration tech we have been installing many many many mini-split systems in the past couple of years here in the arctic Tundra! The multi-head units are poor. The reason being that the outdoor unit does not have twice the area to serve two indoor units as well as two single out door units, this is the main efficiency hit. 4 indoor units is a lot for any size residential installation. How big is the Cape? Generally speaking one unit located in the cooler part of the house will heat the next floor, consequently we install one unit in the L/R and go back a year later and put another unit in the basement a size or two smaller (two indoor units and two outdoor units).

I am not completely sold on them as of yet, due to the above mentioned electric rate unknowns. Electricity would have to be several times what it is now to be more expensive than oil with a mini-split though.

What type of piping does your boiler have, can you split the single zone and have a separate upstairs zone?

TS

 

[STIHLY DAN]

Sounds like a candidate for indoor gasification wood boiler, HPWH, 2 mini splits upstairs.

 

[Timber12vt]

Hey boilerman, the cape is about 1800sq ft for the main floor and 2nd floor, and another 800sq ft in the basement, of which 400sq ft is partially finished. The 2nd floor consists of our master bedroom, a bathroom (unheated), and our daughter's room,

1. If I change my heat to a 2 zone system (which I looked into) that still means I'm using oil to heat my house, which I'm trying to reduce
2. Adding one minisplit to downstairs is an option but our floor plan is not that open.
Aside from the water heater part, the cost (labor and materials) of the 4 zone minisplit and pellet stove after rebates, is $13,000, I calculated that I would save about $1000-$1200 year over oil so a 9-13 year return on investment

Peakbagger, we do like the look of a fire, and figured pellets would be easy and more efficient than wood, so we're hoping the pellet stove will keep the main floor of the house warm and then use the (2) mini splits in each bedroom upstairs to take care of that. The basement still needs heat as we would like to make a playroom for my daughter and a little tv area for myself. The sunroom.....well, it seems as though we will probably get rid of the (2) sliders on the side walls, frame them in, insulate, and put a mini split head in there as well, then we could use that as a dining room. But nothing is locked in stone just trying to get advice on what is the best, most cost effective way to heat this home.

 

[peakbagger]

Keep in mind minisplits aren't cheap and the dealers charge a bundle to do an install that at best should take 4 hours. I would definitely look around and negotiate a package.

 

[Timber12vt]

Peakbagger,

Thanks, I can get them at cost and a friend of mine is an HVAC certified tech who can install them, so that will save me a bunch

 

[chken]

Keep in mind minisplits aren't cheap and the dealers charge a bundle to do an install that at best should take 4 hours. I would definitely look around and negotiate a package.

Aren't minisplits a DIYer possibility if you can get an electrician to wire the box?

 

[Timber12vt]

Sure, but then you need to charge the lines properly with the refrigerant, that is where a DIY'er might have issues if he/she doesn't have the right equipment or install experience

 

[chken]

VERY WELL SAID! ^^^^^^^^^^^^^^^^^^^^^^^^^^

As a refrigeration tech we have been installing many many many mini-split systems in the past couple of years here in the arctic Tundra! The multi-head units are poor. The reason being that the outdoor unit does not have twice the area to serve two indoor units as well as two single out door units, this is the main efficiency hit. 4 indoor units is a lot for any size residential installation. How big is the Cape? Generally speaking one unit located in the cooler part of the house will heat the next floor, consequently we install one unit in the L/R and go back a year later and put another unit in the basement a size or two smaller (two indoor units and two outdoor units).

Okay, let me try to understand. If for example, you had a 36k btu unit with say 4-9k head units, that won't be as efficient as single units, or do you mean since they can oversize the head units, let's say 2-9k head units and 2-12k head units, for 42k total, when the base unit is only 36k, the system is less efficient?

 

[chken]

Sure, but then you need to charge the lines properly with the refrigerant, that is where a DIY'er might have issues if he/she doesn't have the right equipment or install experience

Oh, didn't remember that, just thought I'd seen the install on This Old House, and it looked pretty easy. Charging the lines sounds like a pro-only kind of job.

 

[peakbagger]

I did a self install on a minisplit except for the charging I pad a tech to do it and after watching it, I probably will not pay to do the next one. The game on this is that Mitsubishi and Fujitsu only sell through dealers and the dealers are the only source of service. The discounters on Ebay may be dealers but they can sell low as if the unit dies at an owners site, they arent going to come and fix it and most owners would not send the unit back to get it fixed. In order to charge the lines, someone has to buy a gauge set rated for R410, HVAC vacuum pump an inert gas tank and regulator . If you are willing to take a chance on EBAY chinese stuff I would guess $400 for the equipment. I paid $175 for a tech to do it so not worth buying the tools if you do just one. I was quoted $1500 to $2000 over what I could buy the minisplit and the installation accessories to do a complete install and that is robbery. Of course if it dies, the high markup to a dealer means I get warranty coverage. I asked around and rarely do these stop working unless its owner abuse. I can buy a spare outdoor unit and have it on the shelf for the markup. Some folks and installers skip the inert gas purge so the materials go down to a gauge set and a vacuum pump.

I would suggest doing a self install of a couple of units and then hiring a tech to charge them

 

[maple1]

Since you already have hydronic distribution in place, I think I would consider adding on a pellet boiler, rather than getting the insert, and break your apparently one existing zone into maybe three. And getting a HPWH.

Nothing beats the comfort of hydronic heat.

A move to a mini-split I think I would weigh based on need for summer a/c.

Can you compare the cost of the minisplits AND the insert, vs. a pellet boiler? Seems to me 4 splits would be a hefty cost - have you gotten estimates yet?