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[gandgracing]

A few years ago after I got my boiler all figured out I then hooked up a brazed plate to heat my house water.  Before doing this I could go for most of the winter on just loading once a day.  After heating our water my wood usage has doubled.  Does this sound about right?  We have a rather large family of 7.  I'm thinking I'm going to do away with it cause I'm not sure doubling the wood supply is gonna work. 

[mlappin]

Seems kinda high to me, but we don't have no where near seven in our household.

[slimjim]

Are you NUTS, a BTU is a BTU rather it's wood oil or gas, Imagine if you are burning that much more wood how much oil or gas you will use if you go back to it, tell the family to slow down on the hot water or they should cut the wood and stoke the stove!

[Steinacher Sales]

Just how is your DHW system set up. You are using a plate exchanger?

My Shaver has a built in heat exchanger in the furnace and a pump and a thermostat on the hot water heater. When the hot water get below set temperature the pumped comes on and heat the water.

There are only two of us now except sometimes on the weekend. My hot water heater has the gas turned off to it. I am heating the water right now with the outdoor furnace, thought I would try it once to see how it works out. I'm burning soft wood in it for the time being. Its is working good as far as I can see.

I you don't use the hot water enough the fire will go out though. With your water usage that should not be a problem! LOL

Call me if you like.

Greg Steinacher
618-401-0726
www.midwestoutdoorfurnace.com   

[gandgracing]

This is just in the winter time as I dont use it in the Summer.  My hot line from my boiler goes dirctly to the brazed plate then goes to my heat exchanger in the furnace plenum and then back to the boiler.  The brazed plate heat the water and then it goes into my waterheater which I also turn off my gas to.  Everybody loves the endless amount of hot water and it really shows in the wood usage.  Does it sound like that the way it should be set up?

[mlappin]

Sounds like the proper set up. Takes a bit of BTU's to raise your incoming cold water to whatever temp you use it at.

[hobbyheater]

Doubling of your wood consumption for the added DHW  could be possible especially for a clean family of 7 . For most of the last 30 years our yearly wood consumption has been 4 1/2 cords per year. In the late 80's we took in a destitute family of 10 bringing the total of people living in the house to 17 for 4 months one winter.For that amount of people  living in the house I insisted on daily baths and clean cloths for everyone every day ,with the dishwasher running almost continuously . That year our wood consumption was 7 1/2 cords.

[slimjim]

Thanks for taking care of your neighbors mr. Hobbyheater, that is a noble gesture that we will need to see more of in the future.

[hobbyheater]

Ran a small experiment this morning.
Our heat storage tank holds 1,260 us gallons the hot water tap was run at a flow rate of 1.3 us gallons per hour for 1 hour and in that hour the storage temperature of the tank dropped from 168 degrees to 161 degrees,roughly a consumption of 80,000 BTU'S per hour for 80 gallons of hot water or 1,000 BTU,S for one  gallon of hot water!

[RSI]

Ran a small experiment this morning.
Our heat storage tank holds 1,260 us gallons the hot water tap was run at a flow rate of 1.3 us gallons per hour for 1 hour and in that hour the storage temperature of the tank dropped from 168 degrees to 161 degrees,roughly a consumption of 80 BTU'S per hour for 80 gallons of hot water or 1,000 BTU,S for one  gallon of hot water!

You need 8.3 BTU for every degree you raise the water temperature. You should be able to heat about 150 gallons of water from 60 to 120 degrees while dropping the storage tank temp 7 degrees.

[RSI]

A few years ago after I got my boiler all figured out I then hooked up a brazed plate to heat my house water.  Before doing this I could go for most of the winter on just loading once a day.  After heating our water my wood usage has doubled.  Does this sound about right?  We have a rather large family of 7.  I'm thinking I'm going to do away with it cause I'm not sure doubling the wood supply is gonna work.

What size plate are you using? My guess would be that it slowed down the flow rate of your whole system enough that you are not getting good circulation in the boiler and a lot more heat is going up the chimney due to hot spots causing poor heat transfer.

[gandgracing]

By counting the plates it looks like a 15.  So by going to a 30 might help out?

[slimjim]

It should help but I would check the heat loss in the underground pipe as well.

[martyinmi]

I doubt that heating DHW would double wood usage.
In fact, I'd wager that even with your large family that you'd see more than 25% extra usage.
There's just the three of us here, and I can BARELY measure the extra wood consumption(quite a few variables to take into consideration).
I've measured as little as 5%, and as much as 11% for us.
If you have cheap insulated pex, it could be waterlogged as others have suggested.

How much were you burning vs what you go through now?

[RSI]

By counting the plates it looks like a 15.  So by going to a 30 might help out?

How thick is it? (not including the fittings) Is it a standard size of around 5" x 12"?
What model pump do you have?