Which heater to use

talob

I am building a workshop, it's just over a thousand square feet and well insulated, I have been planing on radiant floor heat what I was thinking wa a closed five loop system with just over eleven hundred feet of tubeing total, I had been thinking of useing a Takagi JR tankless heater, but after reading the pros and cons on and the price of on demand water heaters i'm haveing second thoughts, would a tank type water do the job for me? Thanks

TonyS

Take a look at the new Navien Combi

http://www.navienamerica.com/product/combi_01.aspx?skin=combi_01  I havent used one yet, but I have been using Navien tankless and they work well.  Tankless are nice in a shop where most of the loss is standby.

Karl_Northwind

TAKAGI TK jr

I put one in my shop this fall, and wouldn't do it again.  the head loss thru the heater with antifreeze is too much for most circulators.  I had to run a 2699 on both the secondary loop for the heater and the primary loop into the floor to get enough fluid flow.



after much much digging I was able to come up with 20' head loss thru the heater.

I'm selling it to someone who'll be able to use it for DHW where it belongs.



karl

talob

heater

Karl, thanks for the reply, good info,so what are you going to use? I'm thinking of just trying a fourty gal, gas tank waterheater.                                                         Mike

TonyS

I sold one yesterday

Went to my supplier to order one in.... They wont be available till March sometime. Really irks me, they advertise this stuff in all the trade magazines and when you go to get one, there is none! The Navien though will come with the boiler circ installed and is specifically designed as a combo unit having separate boiler supplies and domestic supplies. Even has a outdoor reset and is very reasonably priced. 10 years on the exchanger and 5 on parts. This could bring condensing technology to the masses.

Karl_Northwind

I'm using

I'm actually moving (building) and taking the garage with me.

long story.

so I won't be heating that slab anymore at all.  my goal was to have a cheap way to keep it heated for a winter, and use the TKjr in the new house.  

Moral of the story: if you want a cheap way to heat a garage quickly and occasionally, put in a unit heater.  I would have spent less money on the heater and on the LP. 



anyone want to buy an LP TK-JR?



the new house will be heated by a condensing water heater (either 199Kbtu voyager or if it has problems, an ao smith vertex thru a FPHE) fueling in-slab and staple up.  There will be a large solar heating system and a loop into the solar tank from the woodstove.   everyone's gotta have a hobby,



karl

talob

Giveing up on radiant

After doing some checking it looks like I might just give up on the idea of radiant floor heat for the workshop if I can't do it with just a cheap tank type water heater. It looks like i'll have a minimum of four grand for a system  that'll do the job, checked with the guy that put the heat system in the house, for the workshop it would be twenty seven hundred for just a overhead furnace, for a dual fuel it would be about five grand that would give me the heat pump gas backup and air, no cheap way to do it. My hobby here has turned into a full time job building the house myself (geodesic dome) I actually have two heat systems here I put in radiant floor heat use a open direct system with a polaris water heater it works great for us, when I checked on air conditioning it was only about three hundred difference for the heat pump and gas backup so that was a no brainer.                   Mike

TonyS

Dont give up

You sound like you went to alot of trouble to build your home. Those

dome homes are a pain to plumb in. So why go and blow anything you save

on your home because of your work shop. Put your tube in the floor, put

2 inches of blue board under it and use a water heater. The important

thing is you get the floor done right. In a few years change it out if

you want. Its easy to change the heat source but very difficult to

change the floor. I have several early radiant jobs in with water

heaters (dedicated) and they work fine.  It sounds like your shop will have a very low heat loss, so the dollar difference between a water heater and a condensing boiler will be low.

Karl_Northwind

forced air

if you're going to use the shop on any regular basis, you should still heat the floor, and use a power vent water heater.



Tony's right, if you're going to heat the floor and the budget's not there for a HE boiler, see if you can find a plumber who's pulled an old water heater, and save your pennies for something nicer.



if: on the other hand you just want to heat it occasionally, and keep it from hitting 20 below, use a forced air furnace.  I'm not a FA installer, but there are cheap ones out there, and just a couple of ducts to the far side of the garage will give you a warmish place to work in an hour or so.  

others can comment



karl

talob

water heater

Yeah I think your both right, been doing some checking maybe a gas direct vent water heater would be the way to go with the radiant floor heat, i've called a couple of different companys the last week on heating equipment and neither one has gotten back to me, guess they just don't need the business these days.