Boilers for small apartments

Littlelandlord

We're looking to replace three boilers lost to Hurrican Sandi on Long Island Hydronic baseboard heat. 2 apts are 600 square ft . + 1 800 sq ft. Apartments have been previously gutted and are well insulated, including interior walls and ceilings. Near as I can tell from the PEX online calculator, we need 24K BTU for the smaller apartments and max 50K for the larger, which has somewhat less comprehensive insulation.



Tenants pay for the their own heat so I'm wondering, do we just get atmospheric units or go for wall hung condensing? Standard stuff (New Yorker) is likely to be more reliable, condensing cheaper to operate.



Additional factor. Atmospheric units will have to be installed in the crawl space, which has flooded twice in the last two years. Potentially we could put the condensing boilers in the apartments. On the other hand, the previous boilers were submerged and repaired in 1992.



Models I'm looking at:

Triangle Tube Challenger Combo

Rinnai e75 cn

Laars Mascot 2



Most wall hung units seem to be oversized for the apartments, even when modulated to their lowest setting.



Any suggestions would be appreciated.

icesailor

Boilers submerged:

I don't know what the rules are in New York, and I thought that this was a Federal FEMA rule, but where I work, after "The No Name Storm" of October 1991, we had flooding in a big area. It was required that ANYTHING electrical, HAD to be raised to a level above the 100 year flood level. If your boilers were submerged in 1992, they should have been replaced and not repaired. They also should have been re-located to above the 100 year flood level. I raised a lot of equipment.

If it is salt water damage, and not replaced, there is no way that paint will stay there. I know of a house that was flooded and they didn't follow the rules. They can not keep paint on the walls. And even though the water was only three inches on the wall, today, it is over 32 inches up. The salt water wichs upi through the sheetrock for years.

Perhaps they are not enforcing this rule where you are. Where I am, they cut the Sheetrock 4' above the floor, raised ALL electrical outlets to above the 100 year level, and replaced everything that was damaged by water.

The Mod Cons would be a far better choice. Don't worry about if they don't fire down low enough.

Have I violated a little secret about the flood damage repair in NY and NJ?

Where I work, they even had to raise electric meters and panels to above the 100 year flood level. If there is flooding, they don't want rescue workers to be electrocuted. Every house in the flooded area was tagged until the AHJ's came and blessed the repairs.

SWEI

this is a known issue in the industry

The 24k load presents a challenge, as there simply aren't small enough mod/cons available here.   A modulating electric boiler will work (and requires no venting.)  



Minimum firing rate on the CC 85s is 23k.  I'd choose a TT PST60 (minimum firing rate 16k) or a Lochinvar WHN 055 (minimum firing rate 11k) for the larger apartment.  If there's room for a buffer tank in the smaller apartments it will help prevent short-cycling during shoulder seasons.

Mark Eatherton

A new entry on the market....

Cadet boiler starts with their smallest boilers input at 40K, and modulates down to 9K.



It IS a modcon, so appropriate actions necessary.





http://www.cadetboiler.com



You will note that the manufacturers address looks REAL familiar...



Niche market, not intended to compete with its other brothers...



ME

kcopp

Electric water heaters....

and Some Rinnai space heaters....

nicholas bonham-carter

Replacing hot water heat

What about connecting the systems together, and using 1 mod on to handle everything. If everything is balanced, and with new insulation, the fuel cost could be added to the rent, with the controls in some secure location.

One boiler sized for the heat loss will surely be less than the cost of 3 separate boilers, and their controls.--NBC

Jack

In this circumstance

I think you and the tenants would be quite pleased with the Rinnai Energysaver that KCop references. We have done more than a few tens of thousands of them in apt buildings all over the Northeast. They are a simple install and last a very long time. A good value in other words.



I represented Rinnai for 20 yrs in New England and still consult with them, so please note my bias, but, then again, I heat my home with them:)



Check them out at www.rinnai.us

DanHolohan

Got it.

Smart, as usual. 

Littlelandlord

Thanks and a follow-up

Thanks for the input. The Cadet (AKA Lochnivar) sounds promising and I've spoken with the LI rep who's referred me to some competent installers.

Wondering about the suggestion that we connect the apartments together on a single boiler. That is actually how I am operating the building right now. Given the difficulty of finding equipment, we threw in a cheap temporary undersized New Yorker, with zone valves, and it is working pretty well.

Conventional wisdom (which I subscribe to, as a landlord since the 80s) is that you want tenants to pay for their own heat and hot water. That was back when boilers were cheap and gas was expensive. I ran the numbers for my building, and I was a little surprised. The two smaller apartments (600 sq ft) were $40-50 per month, including hot water and cooking gas, with a base charge of $15. The larger apartment, 800 sq ft, ran about $60 per month. We were using three one year old Weil McLains, forced induction and fresh air intake, but not condensing, probably a tad oversized at that.

The cost of equipment, plus annual servicing, makes three Cadets look like a pretty poor investment. Everything I've read suggests gas prices will go down, not up.

So here's my follow up question. Suppose we put in one efficient boiler with zone valves and thermostats in each apartment. Any of these fancy new Internet enabled thermostats suitable for a tenant situation? I'm looking for something I could monitor remotely, lock in day time and night time setbacks, and still give the tenant the option of turning up the heat a couple of degrees (but not much more) manually, but have the thing reset itself to my specs every 24 hours.

Otherwise I don't think tenants and thermostats mix. They open windows when the apartment is too hot, then forget to close the windows when the weather gets cold. Locking? Like I said, they could figure out how to put an ice pack on it. Back in the old days in Brooklyn, we used to do stuff like put fake thermostats in an apartment, then hide the real one somewhere is a service closet where the tenants couldn't tamper with it.

I don't plan to replace my temporary boiler until spring, so this will be an interesting experiment if I can find a couple of 'net enabled thermostats to baby sit my tenants.

JohnHenry_2

How about

Setting it up with outdoor reset so that they only get enough heat with the windows closed to get the apartments to around 70* and then let them add their own electric heaters if they want more?

nicholas bonham-carter

Outdoor reset!

John Henry that steel drivin man has got it. The tennants thermostats can drive their pump, or zone valve, and the outdoor reset can keep enough temperature in the system to keep things cosy without the windows open. A buffer tank might be needed to handle the difference between all running at once, and only one zone calling.--NBC

SWEI

ODR works

And if you view an efficient mo/con as a strategic investment, it should pencil out nicely.  By providing a heated apartment at a competitive price, you can be a little pickier about who you rent to (plus pocket a nice profit from the efficiency.)

steve_25

heatwell

How about a Biasi Riva wall hung with outdoor reset had great sucess with this boiler and QHT IN New Hampshire is very knowledgeable and helpful although i do not know if an outdoor reset is available but imagine it must be. also as i have seen posted Rinnai space heaters or if u want to kill two birds with one stone Mitsubisi ductless with heatpump works amazing in northeast believe it or not!