Cold Temp Paper Washing

[Gudmundur Ingolfsson]

About 45 years ago I had a darkroom with cold water only, about 40˚ Farenheit. I washed double weight over night at a slow flow rate and the prints are still OK. It is to be noted that you pay an annual fixed rate for cold water in Iceland, not by wolume.

[Luis-F-S]

I will be using a Versalab 11x14 print washer. My darkroom water heater is only 6 gallon, and currently the water is coming out in the low 50s here in Maine. I have a thermostatic mixer so I can probably get 68 degrees for a while, but I doubt I could maintain it for 30 minutes. Especially if I have to fill the washer first. Any idea how long I should extend a wash to compensate for the low temps?

So why don't you fill the washer and then wait till the heater cranks up again before you begin the wash and then try washing and see what kind of run times you get? If you use a low flow of say 1/4 gpm, it may work. If not adequate, then do fill dumps as suggested on this thread. L

[JMO]

My darkroom is about 58f right now, and cold water is 52f...
I warm up the chemical bottles in a tray of warm water. I'm going to print in a few minutes. I'll start them chemicals at about 75f and they will cool down as I used them. Dektol doesn't work as nicely at room temp.

When rinsing film at least, I just change the water several times over the total rinse time with normal 70f water. It doesn't use much. I do it that way since I am not in the darkroom for the whole rinse and don't want to leave the water running unsupervised.

For paper, I don't actually run out of hot water to mix with the cold. You could also just change the water a few times if you need to conserve hot water.

(I don't conserve; house has a 130 gallon hot water tank for heat storage because of solar hot water. Heat pump water heater would be the contemporary solution)

jp, Your ambient darkroom temps in winter are similar to mine here in Racine, Wisc. Here in the Midwest some of us LFers use electric pig warming mats to keep our trays at the constant, desired temps (and year 'round since my basement darkroom never gets above low-60s F). Check out this thread from Feb. 2019, and the details I gave at #19 in that thread re pig warmers. 'Stay warm....

[Duolab123]

I put a mag drive pump out of a Fuji Frontier color processor on one of my print washers. After 5 minutes in a small swirling Richards type (or a couple minutes in a tray) I fill the archival washer with water and let the pump run. Way higher flow rate, I would need to run 6 gallons a minute to get that kind of flow.

After 10 minutes I drain, refill ( you can have a bucket of water to fill) . Three 10 minute cycles and it's archival as can be.

I always use hypo clearing agent. I wash at 70F but the hypo clear helps with cooler water.

[Eric Woodbury]

Given 50F water with end result 70F water, at 1 liter per minute, requires 775 Watts. Assume that your washer requires 0.25 liters per minute, only 200 watts required (without too much loss). If you start with 6 gallons of 70F water, your water heater should be able to keep up with the demand without issue.

Working the other way around, your water heater is probably 1300 watts (approx). That is almost 2 liters per minute with 20 degree rise.

--ejw--