83trekker
Well-known member
anybody use one for radiant heating, wondering what your costs for runnig it was and how much it was on your electricty bill.
tankless electric water heater
- Thread starter 83trekker
- Start date
Not me, but my neighbor is using one to heat his radiant hydronic floor. He had separate service run to his detached garage, and according to him the electric bill for just that garage is over $100/month in the cold winter months. He wants to hook it up to off-peak, but the electric company won't do it unless he has a backup heat source.
I have pretty much the same size garage, with pretty much the same system, except mine uses a natural gas tankless heater. Mine's only been running for almost a month, but we are both very interested in comparing notes after a few cold winter months. We're in MN by the way.
I have pretty much the same size garage, with pretty much the same system, except mine uses a natural gas tankless heater. Mine's only been running for almost a month, but we are both very interested in comparing notes after a few cold winter months. We're in MN by the way.
I had a 24x26 10 ft ceilings fully insolated and electric was 36$ a month.. I think 45$ was the highest I saw it in winter months with doing alot of welding and compressor going.. using an oil furnace.. I'm in CAnada so it's cold..
I've since moved and just built a smaller 24x22 10 ft ceilings, and am going in floor heat this time.. I just got a tankless JC1 unit for 130$. I'll let you know how it works.. it's rated for 22KW/H max output on 40 amps. I'll have the same tools, the garage is a little smaller, so I should have a basic Idea of the difference in cost for running it.
I've since moved and just built a smaller 24x22 10 ft ceilings, and am going in floor heat this time.. I just got a tankless JC1 unit for 130$. I'll let you know how it works.. it's rated for 22KW/H max output on 40 amps. I'll have the same tools, the garage is a little smaller, so I should have a basic Idea of the difference in cost for running it.
that would be excellent, thanks where in canada are you, im in calgary so really its only about 3 to 3 1/2 weeks out of fall and winter where it gets really cold, theres always a chinook blowing in so it aint bad. I just got to figure out what would be the best route to go before i spend my momney on a system that doesnt work or costs me 200 bucks a month to heat. i got all the pipes in the ground just need the rest done. What and where did you get this tankless JC1 unit for 130$, you have any links i could check it out? All tankless models i have seen have always been in the 1000's for cost. Thanks again
I'm in NewBrunswick.. I spent some time in Calgary lived in the SW in the old army housing up there. Man I wish I was still there.. LOVED IT!..
You guys get your chinooks, but when the cold snaps hit, they hit hard!.. lol..
I got mine on Ebay from a guy in NB so shipping was nothing, but there were 2 other units on there for 100$ each from Quebec. I usually search Canada only Items first to help stop the brokerage BS.. but then there are more options in the US..
I should hopefully have everything up and running by next week.. I'm currently wiring now..
You guys get your chinooks, but when the cold snaps hit, they hit hard!.. lol..
I got mine on Ebay from a guy in NB so shipping was nothing, but there were 2 other units on there for 100$ each from Quebec. I usually search Canada only Items first to help stop the brokerage BS.. but then there are more options in the US..
I should hopefully have everything up and running by next week.. I'm currently wiring now..
Hey, late post and still don't have my heater up yet... it' COLD! hehe got a little busy wiht the kids and I didn't get much time in there. I'm hopeing to have the walls complete by next weekend and I can complete the in floor heat.. it'll prolly be too late by then, but oh well..lol
model is a JC55 I'll have to double check. Here's a basic search I did on Ebay. if you got gas, then mgiht be better off running a gas unit from what I've been reading, but no real world experience..
Tankless water heaters on Ebay
model is a JC55 I'll have to double check. Here's a basic search I did on Ebay. if you got gas, then mgiht be better off running a gas unit from what I've been reading, but no real world experience..
Tankless water heaters on Ebay
bluesman2a
Well-known member
So maybe a little redirect here:
For those of you who have tankless hot water heaters, I'm looking for one for the house (whole house, 4 bedroom, 2 bath, LARGE tub), what are some of the better brands? I have the option of gas or electric, other than ease of installation, is one inherently better than another?
For those of you who have tankless hot water heaters, I'm looking for one for the house (whole house, 4 bedroom, 2 bath, LARGE tub), what are some of the better brands? I have the option of gas or electric, other than ease of installation, is one inherently better than another?
rmack898
Well-known member
I have a Bosch Aqua Star, LPG fired, in a 3BR, 2BA house. It replaced a 50 gal electric unit. I installed it not so much to be more energy efficient, but for an endless HW supply. I had many problems with it the first year and I got to know all of the tech reps at Bosch on a first name basis. I got to the point where I could change out a temp sensor in less than minute. Then they sent me a new computer for it (software upgrade) and I have not had any problems since (over a year). It has reduced my electric bill quite a bit and I have seen no noticable increase in my propane. The only draw back is it takes a long time to get hot water to the kitchen sink. I did not locate the unit in the center of the house (for ease of venting) and it takes a while to get hot water to the end of the line. All in all, I happy with it and would reccommend it.
hemi
Member
This is kinda late to respond, but better late than not at all.
I have a 32 x 72 foot polebarn with hydronic radiant heat had to go with electric power. At the time I was doing my homework on the issue I thought a tankless electric water heater was the ticket, but several sources told me I would be better served with a boiler because a tankless water heater would need to be replaced about every two years due to the demands of heating a garage/building and they are not designed for it . My .002 worth
hemi
I have a 32 x 72 foot polebarn with hydronic radiant heat had to go with electric power. At the time I was doing my homework on the issue I thought a tankless electric water heater was the ticket, but several sources told me I would be better served with a boiler because a tankless water heater would need to be replaced about every two years due to the demands of heating a garage/building and they are not designed for it . My .002 worth
hemi
69Cat
Well-known member
Hemi, I was given similar recommendations. A water heater is not as efficient as a boiler since the water heater operates at a higher temp than what a floor heat system requires. I haven't checked into boiler pricing, what size is yours and cost? I am looking to heat one section to be 30'x50' and fully insulated so am thinking my requirements will be similar to yours.
Ken
Ken
Abodyracer
Well-known member
Here is the website for Rheem. You can also find Rheem heaters labled as Richmond. http://waterheating.rheem.com/
Here is the web site for Bosch. http://www.boschhotwater.com/
Here is the web site for Bosch. http://www.boschhotwater.com/
Last edited:
jeffgrice
Active member
Hi, I plan to use one for the whole house when my tank shows signs of failing.
However I would like opinions on using an electric unit for heating water in cooler weather for the outside hose...for washing cars, boats, house, etc. Are the electric 110 or 220? Would a small unit be good enough for washing a car/boat? I was thinking about putting it on wheels so I could move to different points outside.
Thoughts please...
Thanks.
JEff
However I would like opinions on using an electric unit for heating water in cooler weather for the outside hose...for washing cars, boats, house, etc. Are the electric 110 or 220? Would a small unit be good enough for washing a car/boat? I was thinking about putting it on wheels so I could move to different points outside.
Thoughts please...
Thanks.
JEff
Your math has an extra figure (144?), and is missing some other
unit conversions. In the end, the point is similar.
BTU = amount of heat to raise one pound of water one degree F.
1 watt-hour = 3.4 BTU and it's watt-hour, not watts since both are
units of energy
A 50 degree rise on 1 lb of water takes 50 BTU or 14.65 watt-hours
Getting back to the original problem:
A good healthy flow out of a garden hose amounts to 5 gallons per minute
5 gallons per minute = 40 pounds per minute = 2400 pounds per hour
Assuming a 50 degree temp rise that's 120000 BTU per hour
120000 BTU per hour / 3.413 = 35159 watts
at 120 volts thats 292 amps
at 240 volts thats 146 amps
An even bigger extension cord!
Now, if you wanted to run a sink at 1GPM and could live with a temp rise
of 40 degrees instead of 50, you'd need 29.2 amps at 240 volts, which is
do-able and one of the more common applications of tankless electric water heaters.
unit conversions. In the end, the point is similar.
BTU = amount of heat to raise one pound of water one degree F.
1 watt-hour = 3.4 BTU and it's watt-hour, not watts since both are
units of energy
A 50 degree rise on 1 lb of water takes 50 BTU or 14.65 watt-hours
Getting back to the original problem:
A good healthy flow out of a garden hose amounts to 5 gallons per minute
5 gallons per minute = 40 pounds per minute = 2400 pounds per hour
Assuming a 50 degree temp rise that's 120000 BTU per hour
120000 BTU per hour / 3.413 = 35159 watts
at 120 volts thats 292 amps
at 240 volts thats 146 amps
An even bigger extension cord!
Now, if you wanted to run a sink at 1GPM and could live with a temp rise
of 40 degrees instead of 50, you'd need 29.2 amps at 240 volts, which is
do-able and one of the more common applications of tankless electric water heaters.
PAToyota
Well-known member
danski0224 said:Math was never my strong point....
144 is the number of btu's used to raise 1 pound of water one degree Farenheit.... if memory serves me right.
As FeFarms says, a BTU is 1 lb. of water 1 deg. F.
You do need 143 BTUs to melt a lb. of ice... Perhaps that is what you were remembering.
Abodyracer
Well-known member
jeffgrice said:
Take look at the link in my previous post for Bosch. They have specs on the web site for you to compare.
The electric are 220 and for your area you want the AE125. It uses a 120 amp service for the heater itself. Then you have the rest of the house in addition to that.
Something to keep in mind when looking at tankless water heaters is your ground water temp. As you get farther north the temp drops. A lower incoming water temp will result in a lower output temp.
MyDomain
Well-known member
IMHO Noritz makes the best tankless. They have great specs and they make their own vent pipe which cuts down on cost. See them at http://www.noritz.com/residential.html .
I am an authorized dealer and technical support rep for Noritz so I can speak with authority.
I am an authorized dealer and technical support rep for Noritz so I can speak with authority.