Question about Rinnai Direct Vent Space Heater

[Mike Roy]

We recently closed on nine units in Wiscasset, ME - 3 townhouse style triplexes.  All units are identical at 960 sq. ft., 480 sq. ft. on each floor.  The downstairs consists of a living room, kitchen and 1/2 bath and upstairs is 3 bedrooms and a full bath.  These modular buildings were constructed in 1993 and are fairly well insulated.

My goal is to convert the existing central heat for each building into individual heat and have the tenants pay for it.  I have done this successfully in the past with another building and rents really didn't suffer.

Each building is currently on a central boiler, and I recently had a contractor tell me that he could split off the existing boiler to service one unit and offered the option of boilers for the other two units or a Rinnai EX38 downstairs and an electric water heater in the basement.  The Rinnai option is about $10k less than going with boilers and are also easier to maintain with longer expected life, though I understand I'll be replacing water heaters from time to time.  Right now, I'm leaning toward the Rinnai.

My question for BP is addressed to anyone in a colder climate that has either attempted or has insight about heating a two floor unit with a single Rinnai space heater on the first floor.  Is this a practical solution?

I'm also considering a Rinnai downstairs and electric baseboards upstairs to be used solely as backup during the coldest months.

Thanks very much!  

[Account Closed]

I don't know if it's the exact same model but I had a Rinnai installed in an older home I bought.  The heater is on the outside wall of the front room - the main bedroom and bathroom are in the back of the house.  This is an area where I personally have experienced -17 degree temperatures.  This is a one story, 625 sq ft home.

There is a difference in temperature that (to me) is noticeable - probably about 5 or 10 degrees in the back bathroom.  The house has all new windows (installed right after the furnace) and I've placed ceiling fans throughout the house to keep the air moving.  I haven't had any complaints about the furnace or distribution of heat from the tenant.

Not sure if that helps but thought it might give you ideas.

[Mike Roy]

Thanks @Account Closed  Looping in @Amy A. and @Kenneth LaVoie.  Two Maine real estate veterans who might have tried this or know others who have.

[Brett Jones]

I've installed one of these as part of the heating system in a large single family I own. A 36k btu Rinnai at one end of the place, and a 40k btu gas stove on the other. The Rinnai is a fantastic heating unit, so I wouldn't worry about that part of the equation. One unexpected thing that did come up was an insurance issue. I'm in Maine and my insurance people gave me a hard time about not having a means of specifically heating the bathroom (no baseboards, vent or dedicated elec heater). The issue on their end was the worry of frozen pipes. In the end I was able to stay with the setup I had installed, but for a while it looked like there were going to force me to heat the bathroom.

[John West]

Congratulations @Mike Roy. Those apartments hit the market and were off in a flash. I think you got the deal of a lifetime on those 9 units. I live almost next door. If you ever need anything in the area, let me know.

As for the heating, I know a lot of people around here who use those Rinnai direct vent heaters and they are super powerful. I have a relative who owns three. All three are in two story buildings bigger than those you described, and in all three buildings, its hotter upstairs than down. I'm sure it depends on building design, but I bet you'd be fine.

[Kenneth LaVoie]

Mike, in the name of efficiency, if I owned the building, I would personally do ALL Rinnai's or all central heat, not a combination because of efficiency loss. I have a 2 unit (huge) where each unit has their own boiler. It's an up and down vs. side to side duplex. The two boilers together use more oil than one single boiler heating the whole building would cost. 

Despite the allure of transferring utility rate risk to tenants, I still think the primary focus should be overall building fuel usage. Look at it this way. Let's say you have a duplex with one boiler and you get $700 rent for each (heat included). It costs you 1,200 gallons per year, let's say, in heating oil. Now add a 2d boiler so each unit has their own and tenants pay heat. Now total heating oil usage is probably 1,500 gallons due to inefficiencies (one boiler running, then the other, heat loss from unit 1 up into unit 2, etc.) Now I think this situation puts downward pressure on the rent because the tenants have to pay for 750 gallons each instead of your factoring in 600 each into your rent rate. In other words each apartment just got a little more expensive to heat which puts a little pressure on how much you can charge because SOMEONE has to pay that extra 150 gallons for each unit. Just my opinion. I don't think the situation is "do or die" by any means and I hope my comments are useful. 

[Mike Roy]

@Kenneth LaVoie that is a very interesting outlook, but I would respectfully counter that I think tenants tend to abuse the heat when they are not paying for it.  Early on, I walked into a unit in the winter, heat blasting and the windows wide open.  In only had to see this once to be sold on the idea of transferring this utility cost.   If tenant paid heat reduces fuel consumption by 20% (which I think might be conservative), 1,500 gallons is back at 1,200 gallons with the two systems in your example.  People tell me I could just lock the thermostats at the state minimum, but I'd rather tenants be able to have all the heat they want.

[Ed Emmons]

You might consider leaving the current system as a back up remote set for 60 degrees or so and install heat pumps and let tenants pay for electricity. 
With wall units on first floor it is best to find a way to circulate that heat. At an electric wholesaler or online you can buy very slow moving fans that will bring the hot air from upstairs back down. You almost have to try it first because the layout and exact location of heat source will determine how the heat distributes through the house. Those fans can be installed in a vent but the key is circulation to avoid hot and cold spots.

[Mike Roy]

Thanks @Ed Emmons!

[Kenneth LaVoie]

I actually hadn't thought of that Mike; most of our tenants now are blue and white collar, and we have thermostats that we can actually set the high point (vs. buying a hard coded 72 or 73 degree, etc. that way if we get an older person, or we have a colder than usual apartment we can tweak it up to 73 or 74 thereby "mitigating" the chances of them doing some "low life" stuff like putting ice on it or attempting to bypass. But for the "average" tenant, I think you're right that moving that risk to tenant is a great idea. 

[Amy A.]

I have a 3rd floor apartment with a gas heater and no complaints.  However, since it's on the 3rd floor, I don't think he even turns it on!  I have another building with both first floor apartments with Rennai heaters.  One has complained that the bathroom and back bedroom are too cold, but she didn't move out for many years.  The other keeps it at 80+ so it's really hot, and I'm glad she pays the gas bill!  We are going to remodel the apartment with the "cold" tenant and might add an electric heater to the bathroom.  Once the Rennai dies, I am thinking about changing over to a heat pump with units in both the bedroom and living room.

I must mention that our landlord assn. once had the local fire chief as a guest speaker.  He said that it is illegal to have just a Rennai as a heat source and that a central heating unit is required.  I have never seen this in writing and I think he made it up.  I've seen many apartments with just Rennai heat and mine is Section 8 approved.  I'm glad we got a new fire chief!

[Amy A.]

I once toured a building I considered buying.  One apartment had a Rennai and it was disconnected from the flue!  However, the window was broken in such a way that it was stuck open.  I asked them why they didn't just stuff a rag in the gap to save heat, especially since they were paying for it.  They said, "it's the landlord's job to fix the window".  Maybe the open window saved them from suffocating on carbon monoxide, so I guess it ended up okay.