Domestic hot water help

[maplewoodshelby]

I've got my boiler almost installed and since I spent the extra for the hot water coil which goes in the back of the boiler I guess I should use it. Do you folks see a real benefit of using the boiler to heat your water during the winter. Is there much of a cost savings?

A few questions that I hope someone can help with. Below is a the basic setup that I will be using. Like I said my stove has a domestic hot water coil so its fairly simple

I cant get a diagram to post on here but it basically runs from the boiler coil to the hot water heater and back with a circulating pump right before it goes back in the boiler

I have two hot water heaters for my home. Is there any way to hook both of them up on this loop?

Also for people on here that heat their domestic water. How do you control the temperature going to your faucets and will 180 degree water damage a electric hot water tank??

 

[Gooserider]

I've got my boiler almost installed and since I spent the extra for the hot water coil which goes in the back of the boiler I guess I should use it. Do you folks see a real benefit of using the boiler to heat your water during the winter. Is there much of a cost savings?

It's basically the same deal as with putting the wood boiler in to use instead of your fossil boiler - you don't burn the fossil fuel (or electricity) that you would have used otherwise... No free lunch though, if you heat your water with wood, you will use a little more wood than you would have otherwise... It still takes just as many BTU's to heat the water, doesn't matter if they come from burning trees or burning dinosoars.

A few questions that I hope someone can help with. Below is a the basic setup that I will be using. Like I said my stove has a domestic hot water coil so its fairly simple

I cant get a diagram to post on here but it basically runs from the boiler coil to the hot water heater and back with a circulating pump right before it goes back in the boiler

What kind of format is the drawing you are trying to post? I'm not sure what the full list is for permitted formats, but essentially you need a graphics format like JPEG. Most graphics programs will allow you to save in an appropriate format, or export to one, if not there are usually converter programs available. The other important thing is that the file you want to post MUST have an extension (such as .jpg) and the extension MUST match the file format.

I have two hot water heaters for my home. Is there any way to hook both of them up on this loop?

Probably, though a lot would depend on the details - are the heaters in different parts of the house, or next to each other? How are they plumbed now?

Also for people on here that heat their domestic water. How do you control the temperature going to your faucets and will 180 degree water damage a electric hot water tank??

If you are heating with a boiler you MUST, by code use either a thermostatic control to keep the water heater temp from going over 120*F, or use a "mixing valve" set to 120*F (or less) on the outlet of the tank to keep the temperature of the water reaching the faucets to less than 120*F by mixing cold water with the water from the tank. Generally the latter is a better approach as you effectively increase the size of your hot water tank greatlly by superheating it and mixing it down... As to the question of 180*F water hurting your tank, I don't think it will, but you might need to look at your tanks specs to be sure. You might also need to look at the T&P;relief valve on the tank to make sure that it won't be tripped by water that hot.

Gooserider

 

[rkusek]

I've got my boiler almost installed and since I spent the extra for the hot water coil which goes in the back of the boiler I guess I should use it. Do you folks see a real benefit of using the boiler to heat your water during the winter. Is there much of a cost savings?

It's basically the same deal as with putting the wood boiler in to use instead of your fossil boiler - you don't burn the fossil fuel (or electricity) that you would have used otherwise... No free lunch though, if you heat your water with wood, you will use a little more wood than you would have otherwise... It still takes just as many BTU's to heat the water, doesn't matter if they come from burning trees or burning dinosoars.

A few questions that I hope someone can help with. Below is a the basic setup that I will be using. Like I said my stove has a domestic hot water coil so its fairly simple

I cant get a diagram to post on here but it basically runs from the boiler coil to the hot water heater and back with a circulating pump right before it goes back in the boiler

What kind of format is the drawing you are trying to post? I'm not sure what the full list is for permitted formats, but essentially you need a graphics format like JPEG. Most graphics programs will allow you to save in an appropriate format, or export to one, if not there are usually converter programs available. The other important thing is that the file you want to post MUST have an extension (such as .jpg) and the extension MUST match the file format.

I have two hot water heaters for my home. Is there any way to hook both of them up on this loop?

Probably, though a lot would depend on the details - are the heaters in different parts of the house, or next to each other? How are they plumbed now?

Also for people on here that heat their domestic water. How do you control the temperature going to your faucets and will 180 degree water damage a electric hot water tank??

If you are heating with a boiler you MUST, by code use either a thermostatic control to keep the water heater temp from going over 120*F, or use a "mixing valve" set to 120*F (or less) on the outlet of the tank to keep the temperature of the water reaching the faucets to less than 120*F by mixing cold water with the water from the tank. Generally the latter is a better approach as you effectively increase the size of your hot water tank greatlly by superheating it and mixing it down... As to the question of 180*F water hurting your tank, I don't think it will, but you might need to look at your tanks specs to be sure. You might also need to look at the T&P;relief valve on the tank to make sure that it won't be tripped by water that hot.

Gooserider

My 80 gal State brand electric has a warning that if supplemental heating of water you much be sure the supplemental heat thermostat and built in water heater thermos (1 on top element and 1 on bottom element) are all set to same temperature. What possible reason could there be for this? Is it because the user would get used to 120 water on electric and then get burned uusing the same shower settings when 150 wood heated water was available. This warning label said nothing about a mixing valve even though it detailed how many seconds it would take "X" degree water to burn you. The element thermos had ranges from 120 to 150 so it would appear it could be superheated to at least 150 at a minimum. The relief valve is rated to blow at 200 degrees.

 

[maplewoodshelby]

Well I was trying to post a jpeg image but it will not work. This is my work computer and has all kinds of blocks on it so who knows. I have just about got my boiler plumbed in and hope to take some pics and post on here to see what people think. I along with my neighbor are doing the install and we are working our way thru it.

As far as the DHW hookup. The tanks are pretty much inline with the each other but they are 40 feet apart. The one closest to the boiler is for the kitchen and is a small tank maybe 20-30 gallon. The one farthest away is a large 60-70 gallon tank that is for all the bathrooms and laundry room.
I have debated just skipping the kitchen water heater to make it simple but it would be nice to have completely free hot water and I'm not even sure the smaller water heater uses less power because it probably cycles on and off more

But here is my thinking on the hookup once I find out what temps my water heaters can safely handle

Leave the boiler and go to far 60 gallon water heater (40 feet away) Go in this water heater thru the popoff valve on top and come back out of it at the drain valve at the bottom of the tank. Take this pipe to the top of the small water heater and go in it at the popoff valve on top of this water heater and come back out of the small water heater from the bottom drain. Install circulating pump at this point and run pipe back into the boiler which is 10 feet away. This is my basic plan and I will add back popoff valves and an air vent at appropriate places.

Fellows please chime in and let me know what you think. I can see people are viewing these posts but very few responses and I certainly need some advice

 

[DBoon]

Also for people on here that heat their domestic water. How do you control the temperature going to your faucets and will 180 degree water damage a electric hot water tank??

If you are heating with a boiler you MUST, by code use either a thermostatic control to keep the water heater temp from going over 120*F, or use a “mixing valve” set to 120*F (or less) on the outlet of the tank to keep the temperature of the water reaching the faucets to less than 120*F by mixing cold water with the water from the tank. Generally the latter is a better approach as you effectively increase the size of your hot water tank greatlly by superheating it and mixing it down… As to the question of 180*F water hurting your tank, I don’t think it will, but you might need to look at your tanks specs to be sure. You might also need to look at the T&P;relief valve on the tank to make sure that it won’t be tripped by water that hot.

Hi Gooserider, just to clarify what you said a little more and/or add some additional information that is good to know - in general, if you are heating your water tank in a way that it is likely to heat the water to anything more than 120 degrees F, then installing a mixing valve is recommended. I believe that many current codes would most likely require the hot/cold water mixing system to be of the newer design that will restrict water temperatures to less than 140 degrees F regardless since a mixing valve installed at the hot water tank cannot be relied upon to be the primary temperature protection device. In any case, it is a good practice to have a backup, even if local codes don't require it, and it is something I would probably do even if it wasn't required if 1) I heated my hot water with wood or 2) shared my house with small children or elderly people.

Also, I heat DHW with electric heat now, but when I purchased a hot water tank, I purchased a Marathon polybutylene ("plastic") tank that can withstand temperatures up to 180 degrees F in case I switched to some type of wood burning system in the future. It's worth checking out.

 

[Gooserider]

Well I was trying to post a jpeg image but it will not work. This is my work computer and has all kinds of blocks on it so who knows. I have just about got my boiler plumbed in and hope to take some pics and post on here to see what people think. I along with my neighbor are doing the install and we are working our way thru it.

As far as the DHW hookup. The tanks are pretty much inline with the each other but they are 40 feet apart. The one closest to the boiler is for the kitchen and is a small tank maybe 20-30 gallon. The one farthest away is a large 60-70 gallon tank that is for all the bathrooms and laundry room.
I have debated just skipping the kitchen water heater to make it simple but it would be nice to have completely free hot water and I'm not even sure the smaller water heater uses less power because it probably cycles on and off more

But here is my thinking on the hookup once I find out what temps my water heaters can safely handle

Leave the boiler and go to far 60 gallon water heater (40 feet away) Go in this water heater thru the popoff valve on top and come back out of it at the drain valve at the bottom of the tank. Take this pipe to the top of the small water heater and go in it at the popoff valve on top of this water heater and come back out of the small water heater from the bottom drain. Install circulating pump at this point and run pipe back into the boiler which is 10 feet away. This is my basic plan and I will add back popoff valves and an air vent at appropriate places.

Fellows please chime in and let me know what you think. I can see people are viewing these posts but very few responses and I certainly need some advice

The other thing that can cause problems w/ posting a JPEG is the file size - you need to make sure it's below the minimum... If you are doing something with a camera at higher resolution, a lot of the files can be to large to upload - I find it is best to use a graphics program to convert the image to 640 x 480 resolution, which gives a good balance between file size and picture quality.

As to your hookup scheme, it sounds like a reasonable approach, especially if you insulate all the piping well, and also make sure that you have appropriate flow check valves and plumbing layouts to ensure that you don't get "ghost flow" thermosiphoning when the pump isn't running.

Gooserider

 

[pybyr]

I've got my boiler almost installed and since I spent the extra for the hot water coil which goes in the back of the boiler I guess I should use it. Do you folks see a real benefit of using the boiler to heat your water during the winter. Is there much of a cost savings?

A few questions that I hope someone can help with. Below is a the basic setup that I will be using. Like I said my stove has a domestic hot water coil so its fairly simple

I cant get a diagram to post on here but it basically runs from the boiler coil to the hot water heater and back with a circulating pump right before it goes back in the boiler

I have two hot water heaters for my home. Is there any way to hook both of them up on this loop?

Also for people on here that heat their domestic water. How do you control the temperature going to your faucets and will 180 degree water damage a electric hot water tank??

Huh? What make or fuel boiler? Maybe you've mentioned it lately and everyone knows but me (I have been up to my armpits in other things). How far apart are your two water heaters, and what fuel/ electric do they use, and is there any rhyme or reason as to why there are two of them, separate? Are they tank-type or tankless? The details make all the difference in trying to give a helpful answer.

 

[maplewoodshelby]

My boiler is an Energy King 45ekb with a hot water coil. The two water heaters are 35 feet apart and they are electric. The reason for two heaters is the size of the house and the distance between showers/laundry and the kitchen. It would take forever for hot water to travel to the kitchen from only one big water heater.
Alos, I will be using Pex lines for the domestic hot water hookups from the boiler and return lines. I will try downsizing my file size for future pics
Just an update. got the boiuler installed turned on the water, fixed a few leaks (house had been vacant and some pipes froze) found out my circ pump is locked up and regulator is leaking so getting new ones today. Also probably gonna have to change my chimney flue from 6 to 8 inch. Anybody got any advice for removing clay tile from a 15 ft chimey and replacing with 8 inch without tearing it down?

 

[Gooserider]

My boiler is an Energy King 45ekb with a hot water coil. The two water heaters are 35 feet apart and they are electric. The reason for two heaters is the size of the house and the distance between showers/laundry and the kitchen. It would take forever for hot water to travel to the kitchen from only one big water heater.
Alos, I will be using Pex lines for the domestic hot water hookups from the boiler and return lines. I will try downsizing my file size for future pics
Just an update. got the boiuler installed turned on the water, fixed a few leaks (house had been vacant and some pipes froze) found out my circ pump is locked up and regulator is leaking so getting new ones today. Also probably gonna have to change my chimney flue from 6 to 8 inch. Anybody got any advice for removing clay tile from a 15 ft chimey and replacing with 8 inch without tearing it down?

Bad news on the chimney - what is the current size of the existing flue tile? Are you sure that you will have to do the change - note that a 6X6 inside measure square tile has more cross sectional area than a 6" stove pipe
(approx 36 sq" as opposed to about 27.5) - though not as much as an 8" round pipe (about 49sq") however from what I've seen here, 6x6 square is not that common, but 8x8, which is just big enough to slide a 6" liner down, is...

The problem is that I'm not sure you CAN do a removal and replacement like that for a couple of reasons...

1. The chimney was built around the existing tile - it may be difficult to remove the tile without causing damage to the brick work. I'm also not sure how structurally sound the chimney would be without the liner.

2. Even if you did get the tile out, you probably wouldn't have room to get a larger tile in... You might have room for an insulated liner, however if the tile is removed, you might not be legal / code compliant to install a liner, certainly not an un-insulated liner. It probably would be OK to use the unlined chimney as a "chase" to run a Class A chimney pipe, but again I'm not sure you would have room...

3. There may be code issues involved, I know NFPA requires a tile liner to use as a chimney, but I'm not sure what happens if you try to replace or enlarge the flue diameter.

I would say that this is the kind of question that might need some on-site inspection, by a really good chimney sweep and / or mason, to determine if you really do need to change the chimney size, and if you do what your best approach will be for doing so.

One approach that MIGHT work is to look into one of the cast in place replacement liner outfits - we have seen mixed reviews on them here, some folks have had good luck, others have had "horror stories" and I don't know if they could handle what you need, but it would seem like a possibility.

Gooserider

 

[maplewoodshelby]

Thanks for your thoughts on the chimney. The flue is actually 6 X 6 square tile so that does give me a bit more cros section but I still think I will have problems going from 8 inch stove collar to that. I think for this winter I am going to try it and see what happens. If it wont work, I'll tear it down and build a new one and thats life.
Got my boiler installed and filled with water. Got all the replacement parts and kicked everything up to pressure and so far so good. Left the pump running all night circulating and today just gonna search for any leaks in the heaters. I'm finally starting to understand how this stuff works and I am pretty amazed. I just needed to get in there and start doing it. Now if i dont blow my house up I'll be happy. Gonna try and light her up this weekend and see what happens.

One more question. Does anybody use a battery backup like for a computer if power goes out to keep the pump running for a little while until the boiler can be prepared for power outage? Wasnt sure if that would work or not? Any other good ideas for keeping pump running when power is out.

 

[Gooserider]

I suspect you will be OK doing the reduction if any code inspection folks that you have to get blessed by will buy off on it (this can be a problem) However you will need to stay very much on top of keeping the chimney clean so that creosote doesn't reduce your area further.

A lot of folks do use electrical backups of one sort or another, though if you are going to get a computer UPS, make sure it's a hefty one. In some cases one can replace the battery in the UPS with a larger one, but this can be tricky in some cases. Another option is to get a deep cycle marine battery, a trickle charger and an inverter so as to make your own - if doing this, make sure to properly ventilate, etc. to avoid problems with battery gasses.

Another approach is to build a "dump loop" which is a batch of radiator tubes set up to make a gravity loop that are normally unused - flow to this loop is controlled by an "automag" valve that stays closed as long as it sees electricity, but opens in the event of a power failure in order to dump any excess heat... IMHO the best option is a combination of both approaches.

Gooserider

 

[churchillrow]

We recently had our clay liner removed and a stainless liner put in. The mason had a bunch of extensions he put onto the end of a big drill. On the end of the last extension was a chunk of steel welded on off center about three or four inches square and 1/4" thk. He just beat the clay off. The clay was all out within an hour and he didn't seem concerned with the integrity of the chimney.

 

[maplewoodshelby]

Thanks for the reply. I have since built a couple fires and it seems to draw fairly well. Gonna give it a go and see what happens for this winter. I f i keep it clean it should be adequate for now

 

[Tony H]

Thanks for your thoughts on the chimney. The flue is actually 6 X 6 square tile so that does give me a bit more cros section but I still think I will have problems going from 8 inch stove collar to that. I think for this winter I am going to try it and see what happens. If it wont work, I'll tear it down and build a new one and thats life.
Got my boiler installed and filled with water. Got all the replacement parts and kicked everything up to pressure and so far so good. Left the pump running all night circulating and today just gonna search for any leaks in the heaters. I'm finally starting to understand how this stuff works and I am pretty amazed. I just needed to get in there and start doing it. Now if i dont blow my house up I'll be happy. Gonna try and light her up this weekend and see what happens.

One more question. Does anybody use a battery backup like for a computer if power goes out to keep the pump running for a little while until the boiler can be prepared for power outage? Wasnt sure if that would work or not? Any other good ideas for keeping pump running when power is out.

I think quite a few people me included use a UPS to run BOTH the power to boiler and pump plus any other electrical device needed to keep the boiler in full operation.
With the DHW the piping design is what I would use and I would install some valves at both locations so I could shut water off to each one for repairs or if I don't want to use it.
I have a gas unit and I leave it set at the "normal" setting that way if the boiler is off the heater works just like it used to and I do have a mixing valve on the output set to 120 or so and anti scald valves at the faucets as required by code in my area and a really good idea anyway.

 

[maplewoodshelby]

Can anyone give any recommendations on UPS backups. I'm looking for something to run at least 3-4 hours. The only thing it will will be the thermostat control and a Taco007 circulator

Anybody else see any problems with my piping design on my two hot water heaters. I will basically do away with the water line on the small water tank and replace it with the pipe coming from the larger water tank.

 

[Gooserider]

Can anyone give any recommendations on UPS backups. I'm looking for something to run at least 3-4 hours. The only thing it will will be the thermostat control and a Taco007 circulator

Essentially what you will need to do is figure out the total Watt / Volt-amp load for the stuff you want to keep powered, multiplied by the time you need it, and find a UPS that has AT LEAST that much output capacity - the UPS should have a chart on it's specs that says how long it will power a given size load, go for something a bit oversized as the batteries in a UPS degrade over time, and won't put out as much 4-5 years from now as they would have when new. Note that you will probably be looking at a "server grade" size unit, as loads get heavy over time. What may actually work better is to consider getting a deep cycle marine battery, a charger and an inverter to do your own UPS with a capacity that works better for you. (Keep in mind that computer UPS units are really only intended to keep you up for 15-30 minutes, i.e. long enough to do a graceful shutdown and / or fire up the backup generator...)

Anybody else see any problems with my piping design on my two hot water heaters. I will basically do away with the water line on the small water tank and replace it with the pipe coming from the larger water tank.

The piping plan sounds reasonable, as long as each tank has the appropriate T&P relief valves, etc... Be sure to insulate the circulation lines really well. Another thing to consider is that if you are going to have the circulation pump be switched, is whether or not you would want to put a temperature demand sensor on both tanks, so that which ever one cools down first will call for both to get heated back up.

Gooserider

 

[maplewoodshelby]

Thanks again for the response. My thinking on the domestic water was to run the circulator continously thru each of the tanks and thru the boiler coil. In the offseason just go back on electric. Am I thinking wrong on this. I know there will be a bit more in power but should be much less than running 2 electric water heaters.

 

[Gooserider]

Thanks again for the response. My thinking on the domestic water was to run the circulator continously thru each of the tanks and thru the boiler coil. In the offseason just go back on electric. Am I thinking wrong on this. I know there will be a bit more in power but should be much less than running 2 electric water heaters.

Two issues -

1. Heat transfers both ways - you don't want to be circulating if the boiler is cooler than the tanks, or you will simply be cooling the tanks...

2. There is no sense in wasting energy in circulating water to heat tanks that are already up to temperature...

Thus I would say that you would be best off to have some sort of differential controller that can compare the temps in the two tanks and the boiler, and only turn on the circulator if the tanks need more heat, and the boiler is hotter than the tanks

Gooserider

 

[maplewoodshelby]

That does make sense. Since my large water heater is going to be feeding my small water heater I would probably only need to be concerned with temp difference in one water tank and the boiler as they will be using the same water once it circulates. What I am trying to say is that if one water heater is up to temp then the other one should be fairly close. Now the question is which tank do i want to use to trigger the pump. The smaller tank which will be fed from the bigger tank (but will probably cool off faster due to volume) or the big tank. Again the smaller tank only runs the kitchen dishwasher and sink so it is not critical to be hot all the time. I would think warm would do fine. The larger tank runs the showers and laundry and will also feed the smaller tank so I'm guessing using the large tank for the pump trigger. Any thoughts or problems with this?

 

[Gooserider]

The possible problem I see with only triggering circulation on one tank is that from your description it would sound to me like you have different times when the tanks are getting high demand. At least in our house, we tend to have two different demand peaks - The morning bathroom rush, where everybody is showering and so forth, with almost all the demand from the bathroom loads, and then the evening meal rush when you have cooking and cleanup afterwards, which uses less water, but almost all in the kitchen.

Thus if you are only triggering off the bathroom tank, the kitchen tank might not be hot enough by the time for the evening cooking load, and you might not have enough bathroom demand to trigger a new heating cycle...

In addition, while you are unlikely to get as many complaints about low kitchen water temps as you would about a lukewarm shower, in practice you really do want HOT water for the dishwasher in order to make it work properly. (Some dishwashers have internal water heaters, but they tend to be energy hogs...)

However depending on how your house does stuff, this might not be a factor, and it may well be one of those "need to experiment to find out" situations. If you think triggering off one tank is enough, I'd give it a try, but keep in mind that there might be a reason to want dual triggers and try to allow for that when picking your control devices.

Gooserider