flash water heater for darkroom?

[NER]

I am planning a new darkroom and considering the use of tankless or flash water heater, probably electric (e.g., Stiebel Eltron Tempra 36 Plus) to avoid the complications associated with gas installation (this darkroom would in that that case require it's own hot water heater and gas connections - a headache I prefer to avoid if possible. Does anyone reading this have any experience using flash units for darkroom work? Any comments or recommendations in that regard? Thanks.

N. Riley
http://normanrileyphotography.com

[Rick A]

I'm not familiar with the brand, but have installed many 5 gal electric "point-of-use" water heaters in small office restrooms. They are usually 110v, fit under the vanities, and (IMO)will heat plenty of water for a darkroom.

[W K Longcor]

I had an 80 gal. electric water heater tank in my darkroom for years. It added a lot of heat to the room in the summer time. One monday morning I walked in to find that the tank had sprung a leak -- what a mess! I replaced it with a tankless, wall mounted unit ( don't remember the brand). I was able to turn down the air conditioner quite a bit. It supplied all the hot water I needed for the darkroom.

If you expect to use the darkroom quite a bit, and use a fair amount of hot or warm water -- I recommend a unit powered by 220 volt lines. The heavier unit will heat faster and cause much less strain on the electric bill.

[jmcd]

I don't know about the unit you are considering, but some things to consider are the minimum flow rate through the heater for it to stay operating, and the ability to adjust the heater's output temperature. I had an older Takagi, and if I was adding just a bit of hot water to the cold, say to bring up the cold water up from 60 to 68 degrees, and the flow was not fast enough, the heater would suddenly cut out and the water temperature would plunge. So I was inclined to run more water than I wanted, or employ various other workarounds. On some newer models the temperature can be adjusted, a feature that would have made the unit work much better for me.

[Eric Woodbury]

I used one in my darkroom for several years and I have a big one for the house. Flash heaters are good for the house, but not for the darkroom. I should buffer that with the gas type since gas heaters have a minimum flow rate. This meant that I could NOT have a continuous flow of warm water. I had either cold at low flow or hot at 1/2 gallon per minute. An electric flash heater should not have this issue, but I would check to be sure.

Now I use a small, 4 gallon, electric point of use heater. I set it to about 90F and only turn it on when I'm going to use the darkroom. I like this very much.

If you do go with the electric, they require a lot of electricity, depending on their capabilities. If you are printing and running the hot water at the same time, expect some voltage drop that could affect print exposures. You'll want a stabilizer or closed loop lamp controller on your enlarger.

[NER]

Thanks very much for the feedback. All of these replies are helpful.

N. Riley
http://normanrileyphotography.com

[Roger Thoms]

I researched on demand water heaters for a small bath house I'm designing for a off grid house that I own in Arizona. I ended up choosing a tank water heater for the design because the on demand water heaters that I was able to find here in the States all require at least .5 gpm flow to operate. This flow rate is fairly high and would have wasted a lot of water.

In the darkroom I often have the hot water facet barely cracked. Right now the cold water is running about 64 degrees and it doesn't take much hot water to bring the temp up to 68 degrees. Something to consider when choosing a hot water heater.

Roger

[Wayne Aho]

I use a small tank electric heater for my darkroom. It is 110v, and about a gallon, meant for a small bathroom sink. It does not keep up maintaining temperature for rinsing, and is somewhat useless. So consider something larger. The previous posting that listed a 4 gallon would be the minimum if I had it to do over. I do have a switch for it in the darkroom, so it is off unless I'm planning on printing.

Wayne

[sgreenberg]

I use one in my darkroom now; I had a 220 unit, but it needed too much flow to work, so I downgraded to a 110 model. One detail not mentioned above; if you're in a commercial space and pay for your own electricity, the load rate you're paying will go way up. If you're in a residential space, your bill won't reflect that.

[bigdog]

I use a small tank electric heater for my darkroom. It is 110v, and about a gallon, meant for a small bathroom sink. It does not keep up maintaining temperature for rinsing, and is somewhat useless. So consider something larger. The previous posting that listed a 4 gallon would be the minimum if I had it to do over. I do have a switch for it in the darkroom, so it is off unless I'm planning on printing.

Wayne

I had a very similar setup in my last darkroom, but with a 2 gallon. Useless.

In the darkroom I am currently finishing, (if I put in hot water) I will install either a 10 or 20 gallon.