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crhyner

How much was your HPWH installed, soup to nuts? How much should a standard electric water heater be, all in?

pecmsg

crhyner said:

How much was your HPWH installed, soup to nuts? How much should a standard electric water heater be, all in?

We're not allowed to talk pricing. Different areas have different costs.

ChrisJ

pecmsg said:

How much was your HPWH installed, soup to nuts? How much should a standard electric water heater be, all in?

We're not allowed to talk pricing. Different areas have different costs.

No,
But I wouldn't expect any difference in installation costs between a standard electric water heater and a heat pump one other than the cost difference for the heater.  

Larry Weingarten

Hi, There might be some additional cost to install a HPWH where a standard electric used to be. The plumbing connections are often on the side of the tank, so re-piping might be needed. Also there is condensate to deal with. The heater needs to be installed so there is unobstructed airflow in and out, which might mean it needs to be moved a little from where the old tank used to live. In California, this means earthquake strapping just got trickier. All small costs...

Yours, Larry

crhyner

So, this is going to make me seem like a total idiot, which I may be, but, whatever. I was still thinking about this issue and I was poking around my oil furnace, and I found...a thermostat. Last year I turned my hot water tank down to 120, from wherever it was at, thinking that it would save some money on this issue. However, I didn't think about this setting on my furnace. When I found the low and high thermostat settings on my furnace, they were something like 160-180 degrees. So, that's the temperature the furnace was maintaining and keeping water at, even though the water tank was at 120. I turned the furnace thermostat to 120. I'm going to go ahead and bet that this was a big part of the problem...

Alan (California Radiant) Forbes

So, with your boiler's operating limit set at 120F and your DHW set at 120F, heat transfer will be VERY slow. It probably ran for hours and short-cycled like crazy.

I think you may have gotten to the bottom of it!

ChrisJ

Alan (California Radiant) Forbes said:

So, with your boiler's operating limit set at 120F and your DHW set at 120F, heat transfer will be VERY slow. It probably ran for hours and short-cycled like crazy. I think you may have gotten to the bottom of it!

I think you read their comment backwards.

It was set higher.
They lowered it to 120.

crhyner

OK, so what should I set the boiler and water tank to?

crhyner

Also, it's an indirect water heater.

hot_rod

A complicated calculation these days on water tank temperature. 120f is adequate for household use, but concerns about bacteria, legionella specifically have people setting tanks at 140, using a mixing valve set at 120. So, of course the boiler needs to be able to run above 140. Many boilers have the ability to run on one temperature for heat, and go up to 180 or more when an indirect tank calls.

Regardless if you decide on 120 or 140, allowing the boiler to go to 180 covers the indirect fast, so it can go back to the heating load.

Did your boiler have a tankless coil?

So it depends on what boiler you have and what controls are on it. Also what type of heat emitters, fin tube, radiators?

If your furnace is an oil fired boiler, probably do not want it running below 150ish🤓

bburd

@crhyner the boiler must run at a higher temperature than the indirect tank thermostat setting to transfer heat to the tank. The greater the temperature difference, the faster the heat transfer.

Also as @hot_rod pointed out above, you need to keep your boiler from condensing on the fire side to protect it from corrosion.

To prevent the growth of legionella bacteria, best practice is to maintain the storage tank at 140° F and use a mixing valve to reduce that to 120° F for domestic use. You will need a minimum low limit setting of 150° F at the boiler to do this, and the tank will recover slowly even at that.

ethicalpaul

I can talk costs because I bought mine from Home Depot and installed it myself. It was the Rheem 50 gallon. It was $1300 or so, but now I see it's about $1700. I just had to install a 30 amp breaker and less than 20 feet of whatever gauge wire it was that I can't remember, 8 or 10.

https://www.homedepot.com/p/Rheem-Performance-Platinum-50-Gal-10-Year-Hybrid-High-Efficiency-Smart-Tank-Electric-Water-Heater-XE50T10H45U0/312742081

IIRC, new jersey paid me about $700 to install it. This wasn't a tax credit, it was a check they sent me and it required just a little paperwork and verification on my end.

Part of that was I had to get it permitted and inspected and it passed no problem. It took me a couple hours to install it, I just slid the box gently down my stairs.

It is wifi enabled, I can and have turned off the resistance heating completely, Heat Pump only mode. It does not override this mode, as I can easily tell from how cheap it is to heat the water. It is insanely cheap.

I have never run out of water even though we have a large soaker tub (but we are just two in the household). It comes from the factory with a pretty conservative set point, like 120 degrees or something. I bumped it to 130, which gives me more hot water due to mixing but since I never seem to run out, I might lower it back down. 25 cents per day.

I still can't believe anyone, ANYONE runs their boiler in the summer to heat water when this technology is so readily available with a 10 year warrantee.

ChrisJ

ethicalpaul said:

I can talk costs because I bought mine from Home Depot and installed it myself. It was the Rheem 50 gallon. It was $1300 or so, but now I see it's about $1700. I just had to install a 30 amp breaker and less than 20 feet of whatever gauge wire it was that I can't remember, 8 or 10.

https://www.homedepot.com/p/Rheem-Performance-Platinum-50-Gal-10-Year-Hybrid-High-Efficiency-Smart-Tank-Electric-Water-Heater-XE50T10H45U0/312742081

IIRC, new jersey paid me about $700 to install it. This wasn't a tax credit, it was a check they sent me and it required just a little paperwork and verification on my end.

Part of that was I had to get it permitted and inspected and it passed no problem. It took me a couple hours to install it, I just slid the box gently down my stairs.

It is wifi enabled, I can and have turned off the resistance heating completely, Heat Pump only mode. It does not override this mode, as I can easily tell from how cheap it is to heat the water. It is insanely cheap.

I have never run out of water even though we have a large soaker tub (but we are just two in the household). It comes from the factory with a pretty conservative set point, like 120 degrees or something. I bumped it to 130, which gives me more hot water due to mixing but since I never seem to run out, I might lower it back down. 25 cents per day.

I still can't believe anyone, ANYONE runs their boiler in the summer to heat water when this technology is so readily available with a 10 year warrantee.

I wonder how useful that warranty really is, especially to anyone that DIY
From my POV boiler and WH warranties mean very little to someone like me. Even though I install it better than most, they don't care I'm not a professional.

crhyner

@ethicalpaul Yes, eventually I will get one of these. I'm sort of handy, but putting it in myself might be above my skill set especially with the little ones amplifying the stress level/lack of free time issues. I'll get there.

@bburd Thanks for your comment. So, I don't use this furnace to heat my home, just for the hot water. My initial reason for posting was because we're burning too much oil. Hypothetically, if I keep my indirect tank at 130 and the furnace at 140, I'm assuming we will be burning less oil than if we keep the furnace up at 160-180? I'm not particularly concerned with recovery time, my priority is safety (obviously) and lowering oil usage. I'm correct in this thinking?

Thanks,

Charlie

pecmsg

@crhyner What do you heat the home with?

Am I correct you're running a boiler to make how water in an indirect heater?

Cheap solution is an Oil fired HW heater.
Best solution is the H P W H.

crhyner

Yes, in my initial post I showed a picture of the furnace we're using. We heat with a wood stove, a couple of supplementary oil filled electric heaters in the bedrooms at night. It's warm.

pecmsg

Your wasting a lot of money using the Electric heaters!

Any way of zoning the bedrooms separately?

KC_Jones

Based on everything you posted the real solution to how you are using things is to abandon the indirect and put in a dedicated water heater. I'd speculate the payback would take a year tops. HPWH, electric, or possibly even oil fired, though that would probably be my last choice these days.

pecmsg

KC_Jones said:

Based on everything you posted the real solution to how you are using things is to abandon the indirect and put in a dedicated water heater. I'd speculate the payback would take a year tops. HPWH, electric, or possibly even oil fired, though that would probably be my last choice these days.

But what about the electric oil heaters in the bedrooms?

KC_Jones

pecmsg said:

KC_Jones said:

Based on everything you posted the real solution to how you are using things is to abandon the indirect and put in a dedicated water heater. I'd speculate the payback would take a year tops. HPWH, electric, or possibly even oil fired, though that would probably be my last choice these days.

But what about the electric oil heaters in the bedrooms?

What about them? Not my house to decide how they heat it. They are asking how to lower the cost to make hot water for showers and faucets. If they want to spend money running oil filled heaters in their bedroom that's on them. Makes zero sense to me, but I don't live there.

pedmec

I'm gonna guess that maybe your might losing a lot of heat to the basement because your not running the boiler as cold start boiler. I would check to see if the boiler is trying to maintain a minimum boiler water temperature. Do you know what type of control is being used. The assumption is that the hot water is causing your problem but maybe its that your trying to maintain a minimum temperature in the boiler and its giving a lot of heat off to the basement. my recommenced set up would be:

The boiler should be set up as a cold start.
increase temperature in the indirect.
install mixing valve on hot water outlet and set for recommended temperature.

its a lot cheaper to maintain the domestic hot water temperature in an indirect hot water tank than it is to maintain boiler temperature in a boiler. Most indirect hot water tanks lose about an 1/2 degree an hour on standby.

ethicalpaul

> The boiler should be set up as a cold start.

The boiler should have been scrapped long ago

crhyner

Alright, let me back up here because I know you all know more about this than me, and I want to be making the right decisions.

We've been in our house 8 years or so. It's approx. 100 years ago, stucco, no insulation in the walls. It's all one heating zone with my furnace, 8 radiators or so. I've looked into insulation and it's not really a good idea for a number of reasons, so I've done my best to air seal everything as much as possible. In short, the reason insulation isn't viable is because it'd involve drilling like 200 holes on the exterior of the home, blowing in insulation, which could cause rot, might not stay where it's supposed to, etc. I'd rather not get into this discussion.

So, a few years ago I decided to get a wood stove, which works great. It was my thinking that having the stove would cut back on oil costs, which it has, and everything is very warm in our main living area. I know people said the oil-filled heaters in the bedroom are a bad idea, but they're supplemental to the wood stove, on at night only, on low power, and seem to not jack up out energy bill too much.

But, now that I'm paying more attention to the issue, I realize I'm still buying a lot of oil, just for heating the water.

So, that's why I posted. I mean, what do people recommend? I'm pretty sure revamping the heating system to multiple zones would be expensive. We want to steer clear of oil, if possible. I am open to suggestions for what makes the most sense. Thanks. Leaning towards getting a HPWH and saying goodbye to the furnace. What's most cost effective? Thank you everyone.

crhyner

I am open to suggestion here...just gathering info. If it makes sense to burn more oil and just the radiators, I'd do that. But, I think it sounds like the HPWH for water, plus my stove for heat, and a LITTLE electric SUPPLEMENTAL heat in the bedrooms when it's really cold out seems to be a good idea. Am I off base? What would you do?

JakeCK

Those holes for insulation can be drilled from the inside fyi. How ever at almost 100 years old you probably have plaster and lathe. It's a pita to patch correctly. 

I've already given my two cents on what you should do. Consider the hpwh.

Also using electric heaters to boost the temp of an individual room a few degrees isn't going to break the bank but I would advise that you reconsider your strategy of using them as a primary means of heat. Any plug in electric heater is a fire waiting to happen. 

JakeCK

ethicalpaul said:

I can and have turned off the resistance heating completely, Heat Pump only mode. It does not override this mode, as I can easily tell from how cheap it is to heat the water.

Not according to the documents provided by Rheem. It can and will override the heat pump and switch on the electric elements if the criteria is met.

They have a pre warm function if the tank is too cold from the flow chart and documentation I've read. Unfortunately I can't find the right flow chart right now.

Now be honest with yourself. You really think you have actual control over the logic the controller on that Rheem water heater is using just because you changed a setting? If it's connected to the internet via WiFi(If you are using their app it is!) you don't even have control over when it updates it's firmware.

bburd

crhyner said:

@bburd Thanks for your comment. So, I don't use this furnace to heat my home, just for the hot water. My initial reason for posting was because we're burning too much oil. Hypothetically, if I keep my indirect tank at 130 and the furnace at 140, I'm assuming we will be burning less oil than if we keep the furnace up at 160-180? I'm not particularly concerned with recovery time, my priority is safety (obviously) and lowering oil usage. I'm correct in this thinking? Thanks, Charlie

That low limit aquastat has a 10° differential on the low side, so if you set it for 140 it will cut in at 130 and out at 140. If there is a separate differential adjustment, anything over 10° adds to the cutout point, but does not change the 10° on the low side. Your circulator will run for a very long time. You will save a bit of oil because the standby loss in the boiler will be lower. I think you will need a low limit setting of 150 for this to work, but you can experiment.

If you’re not concerned about the longevity of the boiler, set it up to run as cold start as others have suggested. That will save you the maximum amount of fuel until you replace it with a dedicated water heater.

hot_rod

JakeCK said:

ethicalpaul said:

I can and have turned off the resistance heating completely, Heat Pump only mode. It does not override this mode, as I can easily tell from how cheap it is to heat the water.

Not according to the documents provided by Rheem. It can and will override the heat pump and switch on the electric elements if the criteria is met.

They have a pre warm function if the tank is too cold from the flow chart and documentation I've read. Unfortunately I can't find the right flow chart right now.

Now be honest with yourself. You really think you have actual control over the logic the controller on that Rheem water heater is using just because you changed a setting? If it's connected to the internet via WiFi(If you are using their app it is!) you don't even have control over when it updates it's firmware.

It could be as simple as removing a wire from the back up element, the control cannot override that🥴. My AIO Smith gas ho only function and I confirmed that over several cold start 50F runs

JakeCK

hot_rod said:

JakeCK said:

ethicalpaul said:

I can and have turned off the resistance heating completely, Heat Pump only mode. It does not override this mode, as I can easily tell from how cheap it is to heat the water.

Not according to the documents provided by Rheem. It can and will override the heat pump and switch on the electric elements if the criteria is met.

They have a pre warm function if the tank is too cold from the flow chart and documentation I've read. Unfortunately I can't find the right flow chart right now.

Now be honest with yourself. You really think you have actual control over the logic the controller on that Rheem water heater is using just because you changed a setting? If it's connected to the internet via WiFi(If you are using their app it is!) you don't even have control over when it updates it's firmware.

It could be as simple as removing a wire from the back up element, the control cannot override that🥴. My AIO Smith gas ho only function and I confirmed that over several cold start 50F runs

I could have sworn I read that if the controls detected a fault, including with the elements, it would shutdown. I could be mistaken.

Don't get me wrong I have no problem modifying equipment to make it do what I want. I have on more than once occasion taken the sledge hammer approach to taking control of something that some software developer thought they knew better. Just ask me how I keep windows 10 from updating when ever it wants to... 
But often going that route can cause unforseen issues.

Here are some of the flow charts Rheem has put out for their heat pump water heaters. But it is from 2009 and doesn't match up with their latest tanks. It is actually missing several modes including high demand and heat pump only. I can't find the one I referenced almost a year ago. :S 

JakeCK

Also 50f supply water isn't that cold. The water around my parts of the world will get down into the upper 30's by late Feb. It hurts the teeth.