Individual heat in apartments

Steamhead (in transit)

has other advantages as well:

1. All your combustion equipment is located in one place, which can (and should) be secured against unauthorized access. This sidesteps the problem of tenants tampering with the equipment.

2. The equipment room can also be made fire-resistive.

3. If the equipment malfunctions catastrophically, the chances of fire damage or carbon-monoxide infiltration in the apartments is greatly minimized.

4. When the equipment needs servicing, it is usually not necessary to enter individual apartments to do so.

Is this a steam or hot-water system?

<A HREF="http://www.heatinghelp.com/getListed.cfm?id=367&Step=30">To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"</A>

fredo

New individual heat in apartments

Hi all,

Does anyone have an opinion on installing individual heat in apartments / condos? We are working on a 20-unit, 4-story wood-frame apt building that has been damaged in a fire. The building has been stripped down to the studs. The existing heat was provided by radiators (old-timey cast-iron with big decorated fins), powered by an ancient gas boiler in the basement.

Since the structure is down to the studs it seems a good opportunity to replace the old central system wich individual heat with a heat source in each apartment. Gas seems best because (a) all apts already have individual gas meters, and (b) tenants hate baseboard electric.

It makes sense to switch to individual water heaters as well.

The units are mostly one-bedrooms, about 600 sq ft. The building will be insulated and dbl-pane windows installed. We are in Western Oregon so winters are pretty mild. Any idea what BTU rating we should be looking at? Is 50,000 BTU or thereabouts appropriate?

Any unit(s) we select will have to be installable in very tight quarters (the plan is to house them in very small utility closets), and, I assume, direct-vent.

We've done some research and these are the possible solutions we came up with:

1. Conventional forced-air furnaces and water heaters;

2. Combo boiler / water heater units that would use the existing radiators with new piping;

3. Combo boiler / water heater units, but with radiant floor heat. The heat elements could be installed fairly easily from below since all ceilings have been taken down.

For 2 and 3, the other question what kind of combo boiler / water heater? We saw the water heater-based kind (Bradford White), and the boiler-based kind (Weil-McLane Ultra, Lockinvar Knight, HT Munchkin, etc.).

Net cost is a big consideration of course, but so are comfort and energy conservation. Any feedback, including on the compared costs of the three solutions, will be great! Thank you very much.

Timco

Here in UT there is a company that moniters the usage of the circs from a single boiler and seperates the gas bill accordingly. It would seem this would be the most cost-effective method to break down the usage and have each unit have it's t-stat and own water heater. For boiler size, you need a real heatloss. (see Heat Loss Calcs on top of page) I would re-use rads if ok, or go BB heat.

Tim

Perry_2

The best options....

OK, I'm a homeowner - but also an engineer; and interested in efficient heating and utilities.

I long ago studied the effieciencies of heating multiple units (and houses). Centralized boilers always won out over individual units with one exception: The cost of running supply and return piping between lots of existing buildings (i.e. tearing up streets to install a multiblock heating system does not work well financially - installing it as part of a new development could be long term very efficient).

The key is installing good flowmeters on each appartment - and the world has come a long way with those options.

You are probably best served by an initial cost, fuel usage, and maintenance cost - by installing two or three modulating boilers; with a system that tracks water usage by each appartment. This applies to both heat and domestic hot water. You might even be able to apply some form of outdoor reset curve to the heating system if their is sufficient radation in all of the appartments.

I'd be looking for vendors who have some history in supplying the controls and flowmeters for such a system.

I have never understood why so few neighborhood heating and cooling plants have never been built in the US. Makes great economic sense for a new development. I guess people in the US are so used to having thier own heating and cooling plant - and so mistrustfull of any centralized anything. (Instead of a gas line to the house - you get a hot water line or a chilled water line - or both).

Perry

fredo

Thank you for your replies, you are all making some good points. I should have indicated that down the road the building may be sold as condos. In that context it makes a lot of sense to have individual systems that are billed directly to the condo owners and would help greatly reduce HOA dues.

If you guys had to make a choice between individual forced air furnaces plus water heaters, and combo boilers reusing the existing radiators, which would you go for, and how would they compare pricewise?

Also, someone recently mentioned 'mini-split' heat pumps, do these make any sense in this context?

Thanks

Kevin_in_Denver_2

mini-splits

In most locations nowadays, a heat pump can operate cheaper than natural gas. And A/C comes at no extra charge.

Mini-splits are definitely worth checking out. Computer simulations can be done to show the operating cost savings.

Unfortunately, in situations like these, since the occupant pays the bill, the builder won't pony up now for savings he won't see. Lowest first cost rules.

Joe Brix

Unfortunately

where are you going to put all those individual mini-condenser units? I say PTAC or vertical PTAC and electric HWH. If you want to utilize the gas for heat/HW, they make PTAC's with hot water fan coils. Get a DV combo wall hung boiler or combo HW heater. We all love radiant heat but in a multi-story multi-unit building, there's too much of a chance for damage from leaks, etc.

http://www.retroaire.com/pdfs/vpac-brochure.pdf

Phil Simon

Keep the units seperated is the best way, you pay for what you use. I own a couple of rental houses on Long Island and can remember seeing the windows open in the middle of winter when there was only one boiler and I was including the heat in the rent costs. When the boiler was replaced and they started paying there own heat costs the calls I got were for windows that were too drafty. People don't care to conserve when they are not footing the bill. Keeping everything seperate gives them a reason to save.

Ted_14

WOW!!!! Well said. I own multi family units also. windows all ways seem to be open in the winter and the circ hot enough to fry an egg on . The excuse, we were just airing out the apt. Looking into installing a Tekmar managment system.TENANTS SHOULD ALL ROT IN HELL!!!!!!!!!!!!!!!!!!

Perry_2

I never suggested that tennants should not pay heat

Please reread my post above. The tennants usage would be metered - and billed for their use. I know such technology and systems are out there. Installing a common boiler system, with meters, is cheaper to install. More efficient to operate, and cheaper to service overall.

All you have to do is bill the tennants for their fair share (and be able to demonstrait what their fair share is).

Perry

Long Beach Ed

Tekmar for Tenants

The tekmar stuff is the way to go if YOU are paying for and controlling heat. Either use their thermostat or their boiler controller and put a sensor in each apartment. I use the ones that look like blank switch plates.

Can't be beat.

Then I mount a round thermostat on the wall that's not wired to anything so they have something to play with.

Constantin

Hi Perry,

I totally agree with you that from a cost/efficiency point of view it probably makes sense to have one central boiler plant and then to meter BTUs as needed.

Yet, the actual metering devices are not cheap and there is always the question of whether the meters will stand up to a court fight. IIRC, someone on the wall posted a story a while back where an apartment building owner who metered the heat was sued successfully into abandoning the meters.

Individual heating plants would certainly cut down on the administrative aspects of running the place... everyone would "own" their heating plant. Yet it is so hard to find a semi-efficient solution for such small firing rates and you lose "valuable" space inside apartments.

So my vote would probably be for a metering solution that is put into the lease in ironclad terms.

Joe Brix

Sticky problems come up on

how to calculate? Circulator run time? What if the top floor apt has a higher heat loss then the same size apt on the ground floor? Much easier to sub-meter gas or water usage. But I guess everything could be spelled out a head of time in a lease agreement.

Constantin

There are dedicated devices for this purpose...

... they use the flow (via a water meter) and the ΔT to derive how many BTUs were dropped into a apartment. If you want to go really simple, give everyone the same water temp via constant recirculation, then use a water meter for the heating circuit in each apartment and appropriate fuel usage according to the water meter usage. It's not entirely accurate (there are obvious ΔT issues) but may be good enough as long as no one has vastly different temps in their supply and return.

Some water meters even have reed switches in them to make automating the process simple. At $90 a water meter (for a 3/4" version) and a bit of wiring, you could incorporate the water meter into a utilities' panel outside each apartment. A 1-wire system with a counter-chip for each meter is a couple more bucks but would allow the super to account for all meters from one location and minimize piping (i.e. one main per service per floor, not hundreds of pipes snaking up from the basement).

Three meters per apartment would do the trick: One for DCW, one for DHW, and one for heating. At $270 per apartment, I bet it's cheaper than individual water heaters, space heaters, etc. Put TXVs on the baseboard and a variable-speed pump or pressure-bypass on the main heating circuit and you've got KISS heat in each apartment plus accountability for those who want to emulate tropical conditions.

Mix the system circuit via a OR controller and watch the BTU usage drop. The only trick with OR is to size the baseboard in the more exposed locations (under roof, corners, etc.) to meet the higher heat loss than in the more 'sandwiched' apartments so that those denizens remain just as comfartable at the same water temperature as the rest of the complex.

fredo

All,

Thank you for the good suggestions. In addition to the condo conversion factor, there are also other strikes against the central boiler:
1. Boiler needs to be replaced
2. The condition of the ducting and radiators system is highly dubious (106 yrs old and poorly maintained as far as it looks)
3. Sumbetering isn't cheap, also either you do the billing yourself, which is cumbersome, or you use a billing company, which is costly.
5. Then, as Constantin pointed out, there are the legal aspects. I can think of two potential issues here in OR if a tenant decided not to pay the heat bill: (a) you can't evict them the way you would if they didn't pay rent, and (b) it is against the law for a landlord to turn off utilities (utilities can, but not landlords).

This is a parenthese, but we are going to submeter water & sewer anyway, since our local water utility charges $4,500 per meter (x 20 = $90,000).

All in all there is a very strong argument for individual heat. Now my next question is, what is the most cost-efficient way to implement? As I do more research, it looks like a small forced air gas furnace and an electric HWH in a utility closet (that would also provide hookups for a stacked W/D) might be the least expensive. Not very creative, but cost efficient... What do you guys think? Apts each have their own gas meter.

Thanks.

Brent_2

heat pump

I didn't see you mention if you are planning to provide air conditioning to these apartments. If you are I would go with a heat pump. It seems like since these apartments are so small it would make sense to go with forced hot air with minimal ductwork. You didn't say if the prospective market is high end or middle of the road. What might be acceptable for a $150,000 apartment might not be acceptable for a $300,000 apartment. (adjust numbers as needed but you get the idea)
Electric water heater sounds like a good idea since you won't have to worry about venting.

jp_2

no btu meters.

i like constantines idea. i'll modify a bit.

well designed system, single boiler temperature, TRV's in each unit. everyone pays the 'same' amount for heat. room design temp at 70F. if done well it'll all balance out and be simple.

Dale

Individual units

With only 660 sq. feet and insulation and windows to current standard I would go with a little wall hung boiler or a Tagaki or Rinnai on demand water heater in each apt. I would go to minisplits for cooling, and perhaps heating if you heat loss figures really low. Where I'm from these would be on 2# nat gas with a csst run to each apt. If you plan on higher end apts a little nat gas fireplace is installed. This way you have the tenant pay for both gas and elect. If you ever sell or condo the separate utilities are a good payback. And,as others suggested saving energy seems to start with a tenant bill from the utility. If the mini split heat pump is used you don't need a gas line. I was in N China last year and every high rise had mini splits hanging on the side, some up over 20 stories, pity the maintenance person.

Constantin

Fredo has a point though...

... what if a tenant refuses to pay? A utility can turn off the service, a landlord can't. Something to think about in the lease clauses... or have a local attorney review.

I was trying to keep the house plumbing simple, i.e. minimize the number of pipes that you have to contend with. Running a set of mains down the corridor between condo units would afford easy access (via suspended ceiling tiles), local shutoffs (so not everyone has to suffer if there is a leak, work, etc.), and the meters could be easy to monitor via the reed switches.

Naturally, as with any metering situation, the trick is to prevent nefarious hacks from attempting to mooch free heat/water. More clauses for the lease agreement.

BTW, I got my reed-switch-enabled water meter from DLJ. I am quite happy with it.

Perry_2

What if they refuse to pay...

Evict them.

I once had a lease like that. If you did not pay the share of the utilities - you would be evicted. I paid.

I note that my parents are now living in a trailer court. The trailer court installed individual water meeters on the trailers two years ago - and now bills the water as part of the monthy "rent" bill. Pay in full - or get evicted.

Condo's also have their way of taking care of people who do not pay their monthly fees...

The key is to have it iron clad in the lease - or condo agreement as part of the fees.

As far as future boiler maintenance and replacement cost: The "utility" bills could include a fee for that as well for the condo's. For an appartment. The landlord is responsible - and sufficient money should be built into the rent just as you build in the eventual cost of a new roof, parking lot pavement, etc.

Perry

Pete_28

BTU Metering panel

Ipex showed a BTU metering panel at ISH that could be used with or without a heat exchanger to isolate the subsystem. Uses certified measuring components for both flow and delta T. Results are monitored at a central location either on site or via the Internet remotely.

JackFre

For units this small

I would use the Rinnai on demand water heater for each apt and for the space heating I would use a Rinnai 556WTA Energysaver DV gas fired modulating wall furnace. Go to www.ductlessheating.com for info. The single unit will easily heat the space and the installation is simple. We have done thousands of these installs in New England and NY State

Brandon_4

Did you consider hydronic control panels. Visit this website www.hpscontrols.com

Brandon_4

Have you considered using hydronic zone control stations. Look at these at: www.hpscontrols.com