Oil Indirect DHW - Cost Analysis Help

[bryankloos]

I just purchased it. The Lowes site says 40% off PLUS up to $400 in rebates. I'm fairly certain I just picked it up for $199.
Time will tell once I submit the rebate...
Bryan

 

[mustash29]

I just STOLE it. The Lowes site says 40% off PLUS up to $400 in rebates. I'm fairly certain I just picked it up for $199.
Time will tell once I submit the rebate...
Bryan

Fixed it for ya. LOL.

Killer deal for sure.

 

[BoilerMan]

(broken link removed to http://www.ebay.com/itm/Solar-Hot-Water-Tank-with-Electric-Coil-Backup-115-gallon-/221259624977?pt=LH_DefaultDomain_0&hash=item338419f211)

this is what one of the members here pointed me to (sorry, i forget who). quite expensive but all stainless so should be the last one you ever buy. oventrop is made by another company or something like that. one of them also as dual coil models.

That was me..... I have this model. I do not think the second coil is needed unless you want to have the option to still use oil as a backup. The Oventrop indirect is made by HeatFlo out of Mass. They have ones with the electric element built in as well.

TS

 

[STIHLY DAN]

At $1200 its a no brainer, at $600 one would be retarded not to jump on it.

 

[velvetfoot]

I don't see the GE for $599 in my cart at Lowes. Are you sure Lowes isn't claiming the rights to the rebates in that price?

ac

Are you in CT?

 

[avc8130]

Are you in CT?

No...but I probably COULD be for $600.

ac

 

[velvetfoot]

I stopped off at the local Lowes this morning to buy a plumbing item. I went by the water heaters and there is no indication of a price lower than 1199. I didn't talk to anybody. 600 bucks, though, is a siren's call.

 

[BoilerMan]

I got my Nyletherm 1 for half of your $600.................... If the existing WH is in good condition an add-on unit HPWH is very attractive.

TS

 

[bryankloos]

Before I start ripping apart the existing system, how would you guys recommend using the old indirect WH in conjunction with the new HPWH?
I understand the option of a preheater once I install the gasification boiler, but in the interim what is the benefit of keeping the old set-up in place?
I plan to pick up the HPWH tomorrow, pending we don't have any snow to deal with.

 

[STIHLY DAN]

Nothing.

 

[Brian26]

I purchased the Geospring last year for $900 from Lowes and got a $400 Utility and $300 federal rebate. So paid $200 as well. CT most offer some other rebate or form of savings or something. I have had it for about a year now and it has probably already paid itself off.

 

[velvetfoot]

When I installed my electric resistance water heater, I kept the indirect heater just in case of a real long power outage, for conserving generating capacity. I also am not sure how to incorporate a pellet boiler, oil boiler, indirect, and hybrid water heater.

 

[chken]

Guys,

I had another oil delivery this week and pulled out the spreadsheet. What caught my attention was the amount of oil I was using over the summer which presumably only heated DHW through an indirect DHW tank heated with the oil burner.

From the time we bought the house this summer through our first oil delivery (June 14th - October 24th) we burned 142 gallons of oil over the 134 day period, to give me 1.08gal/day which at $3.54 costs me $3.81/day to heat my hot water. The above calculation of course assumes I didn't use any heat towards October which probably isn't true but I don't know when I first started using heat, so lets round down the numbers in our heads a bit...

This to me seems crazy. Is it possible that I am paying this much just to heat my water? That's almost $1400/year just to have hot water???

Fortunately the oil consumption has been pretty low since installing the insert in November but I am still burning oil to heat the water. That will hopefully change next year when I install a gasser but that is down the road...

So, armed with the above data, what would you do?

1. Switch over to electric?
2. Suck it up until I install a gasser?
3. Tell the wide and kids to take cold showers?
4. Some other option which makes sense financially and keeps the family happy and warm...

If it helps, I have a Veissmann Vitorond 100 with a Reillo burner, running 87% efficiency with the unit being about 8 years old.

All input is greatly appreciated.

Many Thanks,

Bryan

I had a similar setup to you. An 8-yr old Buderus heating an indirect DHW. I've been tracking my oil use, and the roughly 200 days of non-Winter were averaging 1 gal of oil a day. Just like you I was shocked.

So, a year and a half ago I got a GE Geospring from Lowes for $900. I did see that some other NE states had credits from their utilities that drove the cost to zero. I think it was Massachusetts at the time because I sent the info to a friend.

I installed it myself, but had my electrician friend come over to wire the box. He's licensed, I'm not, and the electrical panel always scares me, though I've swapped out breakers before. I pexed my GE to my old indirect DHW in serial. The cold water comes to my GE, then the heated water goes to my old DHW for storage, then off to whatever sink or tub calling for hot water. Works well, and gives me double the hot water storage.

Given the price and rebates and credits, this is one install that is a no-brainer. The payback is at most 2 years, and for some zero years.

 

[velvetfoot]

I had a similar setup to you. An 8-yr old Buderus heating an indirect DHW. I've been tracking my oil use, and the roughly 200 days of non-Winter were averaging 1 gal of oil a day. Just like you I was shocked.

So, a year and a half ago I got a GE Geospring from Lowes for $900. I did see that some other NE states had credits from their utilities that drove the cost to zero. I think it was Massachusetts at the time because I sent the info to a friend.

I installed it myself, but had my electrician friend come over to wire the box. He's licensed, I'm not, and the electrical panel always scares me, though I've swapped out breakers before. I pexed my GE to my old indirect DHW in serial. The cold water comes to my GE, then the heated water goes to my old DHW for storage, then off to whatever sink or tub calling for hot water. Works well, and gives me double the hot water storage.

Given the price and rebates and credits, this is one install that is a no-brainer. The payback is at most 2 years, and for some zero years.

I think I'm getting closer to understanding. But...how does the hot water from the geospring make the indirect hot? Just natural convection or is there a circ pump involved?

 

[mustash29]

It sounds like his GeoSpring does the heating, but it's outlet feeds the indirect. Other than standby losses (and providing the the settings are tweaked properly) the indirect will never call for heat unless there is a huge demand.



I have an 80 gal Slant Fin HWT-80 indirect (glass lined steel) and a 40 gal Crown Mega-Store (stainless) indirect with a pinhole leak in the heating coil. Here are my plans:

Cold feed into the bottom of the 40 gal (cap off the bad coil).
Hot out of the top of the 40 into the bottom "cold" inlet of the 80.
Hot outlet of the 80 to a mixing valve and to the house.
Geyser HPWH sucks from the bottom (cold) side of the 40. Geyser hot outlet injects into the top of the 80, essentially back feeding the entire 120 gallons.

Why?

Summer / Shoulder:

This will give me 120 gal of DHW, all heated over a long time from the Geyser. The 40 will discharge it's volume into the inlet of the 80, effectively keeping the 80's aquastat from needing to turn on unless there is a huge draw.

If there is a huge draw and the Geyser and stored volume are not enough, the 80 will get heated from oil, if I choose to turn it on.

Winter:

Geyser will be off. Wood or oil will take care of the 80 gal. The 40 gal (stainless) won't care if it has cold well water in it.

 

[chken]

I think I'm getting closer to understanding. But...how does the hot water from the geospring make the indirect hot? Just natural convection or is there a circ pump involved?

Exactly as mustash stated. The indirect is additional hot water storage. The standby losses are minimal. Oh, I set the GE for 140 degrees, so that the water in the indirect storage has plenty of headroom for standby losses. Right now, my oil Buderus is still connected as it heats the bedrooms, but the Taco has never called for heating the indirect DHW. Of course that is set for 120 degrees. Basically, the end result is that I get 90 gallons of HW, instead of the 40 in my old indirect unit, or 50 in the GE. Electricity usage is exactly as predicted, about $20 more a month, or $240 a year, based upon my 14.5 cents/kwh.

So, the indirect is just a storage tank in the loop. HW is made in the GE using the heat pump setting to save electricity. When HW is called for, HW goes from the GE to replace existing HW in the indirect tank. The existing HW in the indirect tank goes off to wherever it's called for. Easypeasy. It's just like having a 90 gallon DHW that is heated by a heat pump.

 

[chken]

It sounds like his GeoSpring does the heating, but it's outlet feeds the indirect. Other than standby losses (and providing the the settings are tweaked properly) the indirect will never call for heat unless there is a huge demand.



I have an 80 gal Slant Fin HWT-80 indirect (glass lined steel) and a 40 gal Crown Mega-Store (stainless) indirect with a pinhole leak in the heating coil. Here are my plans:

Cold feed into the bottom of the 40 gal (cap off the bad coil).
Hot out of the top of the 40 into the bottom "cold" inlet of the 80.
Hot outlet of the 80 to a mixing valve and to the house.
Geyser HPWH sucks from the bottom (cold) side of the 40. Geyser hot outlet injects into the top of the 80, essentially back feeding the entire 120 gallons.

Why?

Summer / Shoulder:

This will give me 120 gal of DHW, all heated over a long time from the Geyser. The 40 will discharge it's volume into the inlet of the 80, effectively keeping the 80's aquastat from needing to turn on unless there is a huge draw.

If there is a huge draw and the Geyser and stored volume are not enough, the 80 will get heated from oil, if I choose to turn it on.

Winter:

Geyser will be off. Wood or oil will take care of the 80 gal. The 40 gal (stainless) won't care if it has cold well water in it.

Exactly. Why throw away a hot water storage tank?

 

[Ashful]

We did the same thing with our oil-fired indirect DHW and an electric water heater, back around '83. In our case, it was more about capacity (went from 70 gal to 130 gal), and I'm not sure cost savings was ever considered a factor. Oil was cheap, then.

In any case, electric fed the oil DHW. It made for an almost continuous supply, as the two systems working in series could actually act in an on-demand function to some level, if you managed to burn thru the 130 gallon stored capacity (big house, 4 shower stalls + 1 tub).

 

[SIERRADMAX]

2012, I tracked the oil consumption my 40 gal. DHW used during the summer months and if I remember, it amounted to nearly $110/mo. and that was at the cost of oil 2 years ago. In 2013, I revamped my heating system to include a wood boiler. I had an 80 gallon AO smith residential electric water heater that I plumbed temporarily while revamping the oil system. Ended up costing me on average $50/mo in electricity compared to the same months during the prior year. Upon completion, My state had a $750 rebate & $300 federal rebate for a heatpump water heater install. I plumbed them in series like Joful mentions.

original 40 gallon DHW & a new 60 gallon hybrid.

(broken image removed)

 

[velvetfoot]

2012, I tracked the oil consumption my 40 gal. DHW used during the summer months and if I remember, it amounted to nearly $110/mo. and that was at the cost of oil 2 years ago. In 2013, I revamped my heating system to include a wood boiler. I had an 80 gallon AO smith residential electric water heater that I plumbed temporarily while revamping the oil system. Ended up costing me on average $50/mo in electricity compared to the same months during the prior year. Upon completion, My state had a $750 rebate & $300 federal rebate for a heatpump water heater install. I plumbed them in series like Joful mentions.

original 40 gallon DHW & a new 60 gallon hybrid.

(broken image removed)

I tried to see what was going on with the piping but failed. It almost looked parallel to me. Is the heat pump water heater feeding the indirect?

 

[SIERRADMAX]

I tried to see what was going on with the piping but failed. It almost looked parallel to me. Is the heat pump water heater feeding the indirect?

It's he other way around domestic water supply goes through the indirect (which can be valved off or bypassed) to the heat pump WH. The switch on the wall disrupts the dry contacts whenever I don't want he indirect to call for hot water. I use it when operating the wood boiler solely.

 

[Redbarn]

I'm a bit late to this thread but I installed a Geyser HPWH 3 years ago now.
Pictures are in: https://www.hearth.com/talk/threads/ducting-and-geyser.108580/

Saved 1 gall of oil per day.
The most pleasant surprise was the drop in AC costs in summer.
The oil DHWH is inside the air conditioned volume of our house and so the AC had to shift the waste heat from the oil burner as well as the general house heat.
In our case, when all done, we got summer DHW for just about free and in the shoulder seasons, a barely changed overall electric bill.

 

[BoilerMan]

I'm a bit late to this thread but I installed a Geyser HPWH 3 years ago now.
Pictures are in: https://www.hearth.com/talk/threads/ducting-and-geyser.108580/

Saved 1 gall of oil per day.
The most pleasant surprise was the drop in AC costs in summer.
The oil DHWH is inside the air conditioned volume of our house and so the AC had to shift the waste heat from the oil burner as well as the general house heat.
In our case, when all done, we got summer DHW for just about free and in the shoulder seasons, a barely changed overall electric bill.

I find my Nyletherm (Nyle makes the Geyser) costs about 10-15/month to run. Our electric rate is $0.147/kWh, and we do not conserve hot water in our family of 3.

TS

 

[STIHLY DAN]

That's it you guys suck! I had my hot H2O down, 80 gal pre heated by wood furnace feeding geo spring, works great. Now I have to pipe in another tank post geo for another 40 gal of hot H2O, because its the cats a$$. Ya you suck and thanks for it. (GENIOUS)

 

[STIHLY DAN]

Oh, a math ?? too. What is best having 80 gal 0f 90* H2O feeding geo, or 40 gal of 130* feeding geo.