electric vs. indirect

hotwired

Hi all,

I had an oil fired hot water heater blow a month or so ago on a 7 unit apartment building. We had just replaced the old 72% efficient 1940's oil boiler with a brand new pensotti direct vent. Typical logic would say, okay, now is your chance to install a boiler mate. BEST way to heat hotwater from what everyone tells me, but for some reason I allowed my mind to get involved!! My burner man didnt' help much, he didn't really push me one way or the other ... but I had a thought to I'd "diversify" by using electric hot water heaters. Everyone I've talked to since has thought me crazy.  I'd love to hear from some of you experienced folk on how bad or ok a decision I've made so I'm a little better educated the next time. We now have twin 40 gallon h.w. heaters and my elec bill went from 60 to 300 almost overnight.  Past oil usage June thru Oct was only 216 gallons ($600-$700 for 4 months).  This leads me to my next question...

A landlord mentor who owns 250 units has a trick where he has cold start boilers, electric hot water heaters BUT ... he rigs up a system where he uses a couple of circulator pumps, plate heat exchangers and uses the electric hot water heater as an "indirect" during the winter. So in summer, he uses electricity becuase the boiler doesn't need to run anyway, and in the winter, he switches the units off and runs from the boiler .... I havent' gotten all the detail yet on how to do it but we share the same boiler man and he's done a few for him. Anyone ever heard of this? Does it sound .... sound??

Thanks!

icesailor

Electric Vs Indirect:

It sounds like dog dirt to me.

You found out how bad electricity is already. Cut your losses and put in an indirect.

Your friend isn't far behind in the stupid idea category.

But then, he's smart and I'm not.

hotwired

thanks

thanks. I was hoping for something more technical, but I think I get your point!

RDSTEAM

the only positive about electric

is that its 100% efficient. you might have to pay double every month, but you wont have any waste    try a couple of hybrid heat pump water heaters. you should save plenty of money with those and in the summer it will probably cost dollars a day to run those.

hotwired

hmmm

that is an option becuase i have a two unit with two heating ssystems (coil indirect hot water on both) and was going to add boilermates to those. SO ... rip out the two EHWHs on the 7 unit, drag em' to the two unit (tenants pay ) and install two (or one) 50 gallon hybrid heat pump/ electric -- all the piping and elec. is in place so it won't be TOTAL waste .... hmmmmmm.... just might save my butt after all.

RDSTEAM

glad to

be of assistance.  cost of heat pump is about $1400. plus you can snag the $300 tax credit. total payback for each unit, should be about 3 to 5 years. where are you located?

hotwired

location

I am in winslow Maine -- not the best heat pump territory but this particular basement has been spray foamed and is almost always 65 degrees when I go in there, so it might just be fine.

eluv8

perhaps not

Just to throw in my two cents.



 The GE or the AO Smith heat pump water heater will extract the heat from the space its installed and has requirements on total cubic space and air exchange. If the room is not heated from some indirect source that room will get pretty cold and eventually reach a point that the heat pump can no longer extract the heat from the room. 

hotwired

thoughts

The basement in question is HUGE. about 3k SF believe it or not, and spray foamed nearly floor to ceiling, so very air tight. When it's 0 outside, it's still around 60 in that basement just from the boiler. I have begun insulating the heating pipes, so that will come down some, but I think this particular basement might be a good candidate becuase of it's warmth. At this point, I'm leaning toward the flat plate heat exchange idea where I already have the electric HW heaters in place. I've just shut one completely off so now I have ONE 40 gallon HWH serving 7 units. (1 empty until the first) and no phone calls yet ... I also turned it down a bit from the factory setting. I'm pushing the envelope, but I'll get a phone call if it's not enough. Then I'll tweak the temp first (upward) then return the second to service if that doesn't work, but so far no ringing, so I'm optimistic. Shutting 50% of my EHW's should cut my bill quite a bit I would think ...