tankless or small tank heater?

[Innovate1]

I am planning a 30 x 40 heated detached garage and thought I would do a small 5 - 10 gallon electric heater but I do have gas for the furnace. I don't need huge amounts of hot water and don't expect to use it much. Wondering if a tankless heater might be a better choice? If gas it would need a flue. I am planning a condensing water heater so it will have it's own PVC flue.

 

[432bullet]

I use a Boat / rv 110 volt for my shop works fine. no flu or gas plumb it with pvc and plug it in to a wall socket.

 

[Pluribus]

Assuming you have adequate electrical service, I'd recommend the electric point of use unit. It would be the easiest and cheapest to set up by a huge margin; I would think. If you went gas, not only would you have to cut a penetration for the flue, but you'd also have to run the gas line to the water heater. Tankless requires an bigger gas line over a tank style, and then there's the delay in getting heated water once you turn the faucet on. I'm running a tankless in my house and I hate it.

Forgot to quote 432bullet above, but I think they nailed it with this: "I use a Boat / rv 110 volt for my shop works fine. no flu or gas plumb it with pvc and plug it in to a wall socket."

 

[Copymutt]

I second electric over gas, however don’t go tankless unless your water supply is soft. Otherwise the heat exchanger will plug up pronto.

 

[rsanter]

If you don’t need much. I’m thinking you just want hot water at the sink for the hand wash and such?
I would do a small instahot point of use one like was mentioned earlier.
We had one in an out building office and it always worked fine

 

[kbs2244]

Tankless would cost too much for such little use.
An RV unit will work fine.

 

[scottydosnntkno]

Assuming you have adequate electrical service, I'd recommend the electric point of use unit. It would be the easiest and cheapest to set up by a huge margin; I would think. If you went gas, not only would you have to cut a penetration for the flue, but you'd also have to run the gas line to the water heater. Tankless requires an bigger gas line over a tank style, and then there's the delay in getting heated water once you turn the faucet on. I'm running a tankless in my house and I hate it.

Forgot to quote 432bullet above, but I think they nailed it with this: "I use a Boat / rv 110 volt for my shop works fine. no flu or gas plumb it with pvc and plug it in to a wall socket."

Not all tankless need a bigger line. We use naviens and they can do 199k btu on 1/2” up to 20’. Worst case is OP has to do a 3/4 feed to the garage instead of 1/2. But it’s new construction so the cost difference is marginal.

But a $1500 heater vs a 5gal Home Depot under sink one which will work the same for $200 makes a diff could even set it to a smart plug tied to your lights so it’s only on when the lights are on

 

[bamawildcat]

I've got the smallest point of use Stiebel Eltron heater in my shop. I've got it run to a switch so it doesn't draw power when we don't need it.

 

[samss]

HD online has Atmore brand tankless. I put the 13kw in my shop. Easy install, quick to supply hot water.

 

[tarmy]

I have the same condition...gas and electric available. This is simple, safe and easy to drain when needed.

 

[Innovate1]

A 14 kW tankless takes a 70A breaker. That's practically the whole capacity for the building (90A). A 6.5 kW unit runs on 30A but looks marginal for flow. Looks like a small electric tank unit might work the best. Low current draw and I can turn it off when not needed. 2.5 to 6 gallon, 1500 - 2000 W are common and can heat up in about 30 minutes max.

 

[benjamintmiller]

I have a Stiebel Eltron 9.6kw that I'm going to install in my shop. It draws 40A, so it needs a 50A breaker. It is designed for one medium or high flow sink in a cold climate. Rather than put mine under the sink, I am locating it in a nearby room so I can add a hot water tap for a bucket or hose.

They're about $160 on sale at Menards, which is less than any tank-type water heater I could find locally.

 

[captain14]

Another quick solution just to see how much you need is to get a used coffee urn from the thrift store and heat water only as needed for cleanup. Fill it when you start the job and it’s ready. It doesn’t take take long for 1-2 gallons to heat up.

 

[Turbo]

Another quick solution just to see how much you need is to get a used coffee urn from the thrift store and heat water only as needed for cleanup. Fill it when you start the job and it’s ready. It doesn’t take take long for 1-2 gallons to heat up.

When i was a kid, we used one of these in our pop-up tent camper. Mom used it for washing dishes. Terry

 

[James-W]

Since you are still in the planning stages, just plan to have a small gas water heater in the room with your furnace and vent it the same time you vent the furnace. Natural gas will be about the cheapest way of heating the garage as well as the water.

If you are going to be working on cars/vehicles then I would also consider having a shower in the garage as well. That way when you get really dirty you can shower in the garage rather than go in the house and use the shower. While it isn't really necessary to have a shower in the garage, on those occasions when you get really dirty, if your wife is anything like mine I tend to think she would prefer you showering in the garage. I know my wife would. I can't shower in the garage because I didn't run water or sewer out there. But because you are still planning your garage, you have the opportunity to add a shower. Now is the time to do it, don't wait till you are all done with the building to think about it.

 

[bctexas]

I went with a 7 gallon 110v Bosch tank water heater in my new build. Under $200 ordered on line - I think from Lowe's. Seemed the simplest solution.

We designed the house with a hall bath close to the back door for easy access to a shower, so didn't add the complexity or use the floor space for a shower in the shop.

 

[38Chevy454]

I have a small electric 6 gal 120v/1650w water heater in my detached garage half bath. It is really nice to have warm water to clean up. I heat the garage with propane, so electric was the better choice for me. Also a lot easier to install since no gas and vent lines needed. Being 1650 watts it does not have any real high amp electrical wiring required. It is a State Industries, Proline commercial grade heater specifically.

 

[GeoRoss]

It has been my experience that unless a tankless gas unit is used frequently with shower-length duty cycles they go bad or you need to do much more frequent cleaning. Your best bet is to go for a small tank water heater.

 

[redmondjp]

Another vote for a small, electric-heated tank. I have a 2.5gallon Arston underneath my bathroom vanity, and a 4 gallon one underneath the kitchen sink. Both have been in operation for about 8 years now. I would go with the 6.5 gallon unit for your situation - if you want to fill up the sink with hot water, it will go from hot to warm pretty quickly. The 4 gallon for our kitchen sink is really a bit too small.

 

[wes73]

Small point of use all the way. I've got a 10 gallon. More than i need for normal usage...however, it gets close when washing more than 2 cars back to back. Now i only use hot water in my wash buckets and rinse with cold water...nothing beats washing cars with warm water in late fall early spring...hindsight, i may have gone 20 gallons. it all depends on your use.

 

[Ray-CA]

We have a small 2.5 gallon electric water heater under the sink. Since it's only a couple of feet to the faucet we get instant hot water. I put the unit on a switched outlet so we we got on vacation I can turn it off. Total cost was maybe $100?

Ray

 

[Plump]

Another vote for the small tank. I have a 2.5 under the sink. Takes up very little room, runs off a regular plug, heats VERY quickly. I have it on a simple dial timer so it only runs when I'll be home. A quick flick of the switch if I need it on weekends, and I have hot water in a very short time.

Neighbor has a tankless and hates having to clean it. Blew out a check valve when blowing it out for the winter, etc.

 

[555]

I have a 10 gal 120 volt Rheem in the shop. When I bought it 4 or 5 years ago they were under $200.

 

[sberry]

The smack tank type heaters were invented for this. They were a pain to find 39 years ago when I wanted them, now in all the box stores in several sizes. 2.5 would work for hand wash, would just as soon have a 5 or 7.5, enough to fill a bucket with hot.

 

[climb.on]

I have a Stiebel Eltron 9.6kw that I'm going to install in my shop. It draws 40A, so it needs a 50A breaker. It is designed for one medium or high flow sink in a cold climate. Rather than put mine under the sink, I am locating it in a nearby room so I can add a hot water tap for a bucket or hose.

They're about $160 on sale at Menards, which is less than any tank-type water heater I could find locally.

Same here. I ordered mine from Amazon and got the same 9.6kw. It works just fine to wash hands and fill a bucket of hot water. I don't like the idea of a tank of hot water sitting there heating for years and years when I only use a little bit of it every couple days on average. I think my situation begs for tankless. The more hot water you use (daily at least), the more makes sense to move to a tank style hot water heater or maybe a gas tankless.

 

[mrjohnsmitt]

Another vote for a small, electric-heated tank. I have a 2.5gallon Arston underneath my bathroom vanity, and a 4 gallon one underneath the kitchen sink. Both have been in operation for about 8 years now. I would go with the 6.5 gallon unit for your situation - if you want to fill up the sink with hot water, it will go from hot to warm pretty quickly. The 4 gallon for our kitchen sink is really a bit too small.

I had totally forgotten that that is the exact unit I have in my shop. I don't have a shower, but for filling car wash buckets and washing hands it has served me well for many years. The other up side is that you can buy all the repair parts, thermostats, elements etc. I leave it on all the time. My utility bills hardly ever run over $35-40 in the non heating seasons. Another food for thought moment.