Not Wood but electric boiler size?

[rombi]

I have been thinking about this for some time and think I am going to dedicate the in-floor heat in the dog kennel to an electric "boiler" instead of using the wood boiler. I would go off peak hours so the rate is :$0.05705 per kWh During electric Off-Peak hours. weekends are off peak. my thought is to charge the floor at night let it coast during the day. 600 feat of pex in floor with it well insulated bottom and sides. what size electric boiler should I be looking for? I see they make some designed just for the in floor temp range but I don't know if I need a 10kw, 12kw etc....

 

[rombi]

am I correct in thinking that a 12kw ran for 8 hours is 96 times .05 for $4.8 dollars daily to run it wide open for 8 hours?

 

[maple1]

Your $4.80 is correct, yes.

I have an 18kw for my backup heat but could do with a smaller one. My load is a lot larger than yours.

A 12kw boiler running steady for 8 hours would make about 330,000 btu. So it would depend what your heat demand is. 9kw might even do you. They cycle their elements as needed, so oversizing a bit doesn't impact hugely. Bigger breakers & wiring cost more though - mine needed a 100a breaker, and big honking wire.

 

[Pat32rf]

Love the cheap hydro you guys have down there . I spent 15 years servicing electric boilers mostly 50-600kw in apartments. When I retired I wound up with all kinds of elements, pumps, etc but my last hydro bill cost $.21/ per kwh and that puts resistance electric heating out of my reach. ($151.00 / month for one kw on continuously)
In your case I would just install heat tracing in the concrete floor and forget about pumps, zone valves, etc.
On the other hand, once the pex is in the concrete, you can add a OWB next year

 

[Karl_northwind]

a 6 kw would be plenty for you. if the heat load is in the 3 KW range, doubling that to heat and store at the same time.
how well is the kennel insulated, and are there doors open out to the dog run?

 

[tom in maine]

A radiant floor can deliver up to about 30 btus per square foot. You have 600 sq. ft. which is about 18,000 btus or 6 kw.
That should be the absolute minimum. A little bigger for pick up on cold days would be good.
Of course, the building heat load determines the actual need, but the boiler should match up with the distribution output.

 

[rombi]

ok so maybe a 8kw would be ok? what is a good one without breaking the bank?

 

[tom in maine]

If you want to go cheap, an electric water heater is usually 5.5kw. Controls are not great but it would work. I have had customers do this, using the water heater in a closed loop.

 

[maple1]

Mine is a Hydra (Dettson).

I was also looking at Slant Fin before I found this one, got a good pre-owned deal.

Also have a couple guys I know here that use an ordinary water heater to heat their garages. They don't keep them much more than above the freezing point though. Not sure what size, but my water heater has 4.5kw elements. It has 2 of them (they don't operate at the same time) - a single element heater might have a bigger element than mine, maybe.

 

[tom in maine]

Came across this. Know nothing about it, just FYI.

http://unclehenrys.com/classified/4531216/classified?back=/search/all?sr=39144676#4531216

 

[rombi]

getting ready to buy an electric now. Anybody else have some suggestions for which one to go with?

 

[rombi]

http://www.menards.com/main/heating...4433731612-c-8519.htm?tid=3095201292144199487

this is what I was looking at.

 

[maple1]

Not sure what these words mean exactly, or implications:

• Must be installed with a primary secondary (2) pump radiant heat integrator panel installation as found in Hydro Smart integrator radiant heat integrator panels or warranty is void.

 

[rombi]

i saw that as well. Maybe a way to sell their whole system when all I think I need is the unit and another expansion tank. I don't care about the warranty.

 

[Bob Rohr]

Thermolec out of Canada or Electro NM out of Minnesota are good boilers. Both have out door reset built into the control and staging of the elements with triac relays.

These are designed to be heating boilers, not electric DHW tankless heaters. Find prices online.