Darkroom Heat and Dust

My darkroom is in a very cold part of my basement. In the winter months, the temperature can go so low that Dektol doesn't work. It is walled off from the rest of the basement, which is normal temperature because, like the rest of the house, it is heated by forced air from an oil furnace. I want to insulate the darkroom and install a heating vent.

I should add that I have ventilation now, just no heat. There is a darkroom fan to take out fumes and a darkroom vent in the wall so that the fan will draw air properly. I can tell that some dust gets in via the vent but so far, it is not a huge problem. Most of it winds up on the vent, which I wipe off regularly.

However, forced air is notorious for dust. Have any of you solved this problem? What kind of vent, filter, etc., do you use to keep the dust out? I have also thought of insulating the room and then using an electric heater.

I use an electrically-powered space heater. It's basically an electrical radiator. Therefore, there is no blowing air. It works quite well and it even has a thermostat.

You could get a permanent electrical radiator installed, too. They are reasonably inexpensive.

my ventilation is:
- an extraction duct at the end of the sink where the fixer usually sits. Mine goes into the exhaust intake of the hrv, but an ordinary bath exhaust fan would work here too.
- my inlet is a hollow wall cavity between the studs that frame the walls of my darkroom. . There is an inlet up high, near the ceiling, on the outside of the darkroom, with the vent openning covered wiuth a section of furnace filter. The part inside my darkroom is down near the floor, on the dry side of the room. The cavity os painted black to form a light trap. I find that since the intake is up high, there is not as much dust to suck in as iff it were located down low.

Seasonally I will vaccuum out the floor of the dark room. Usually when I note that dust is building up on top of the enlarger lamp house, where it is naturally drawn to since this is one heat source in the room. I have the central vac power unit out in the garage, so no dust recirculates like the little portable vac units.

As to heat, I would consider getting an electrically powered radiant oil heater, as Photo Jim recommends. They heat by conduction - no fan required, alothough they do take up floor space.

For heat, use an electric oil heater. It is quiet and generates no dust.

For dust, seal up the walls and ceilings, use semi-gloss paint (which is more easily cleaned and attracts less dust than flat paint), filter the incoming air through the ventilation system.

Keep the floor very clean. I never wear street shoes in my darkroom.

Electric oil heat works great and there is no dust moving around the darkroom. A problem you might have is static that gets worse in the coldest time of winter. Can you add some humidity?

Marcus

I use a small convection oil heater in winter. The air intake is filtered with standard furnace filters doubled up and changed on a regular basis. Static is rarely a problem even on the driest of days because of the running water in the print washer. Temps here are very mild in winter so the main concern is keeping cool in the summer.

Thanks for the responses, including you guys in warm climates! I had never heard of an electric oil heater but I checked them out online and I am going out today to take a look at some.

Marcus, I will keep on eye out for static, although as with Wade, my darkroom tends to be sufficiently humidified by the print washer and other sources of water.

Wade, although I am a little jealous of that wonderful California climate, on the hottest days of summer (and it can go as high as 100F), my darkroom never goes about about 72F. We don't have air conditioning in the house so on extremely hot evenings, a printing session is a nice little break. Mind you, in the dead of winter when the outside temperature can go to -40F (yes that is minus 40F), the darkroom can go as low as the high 40s/low 50s. It makes printing feel like outdoor work.

Time for insulation and an electric oil heater.

There are very few houses in So. Cal. with basements. Wish I had one! Temp control would be much easier. Winter temps East of San Diego are in the 30-40F range at night. In summer it can reach 110-120F but luckily not all the time. I generate most of my own electricity using wind and solar power so the air conditioning (which is a swamp cooler) doesn't cost much to cool the entire house.
The important part is to keep the filters clean to avoid blowing dust everywhere.

Northern California here. Darkroom in garage, seems to sit at a constant temperature of 18-22C depending on outside cold and time of day. Usually it's 18C on the dot at night. I typically don't do any heat regulation, I just wear another layer if it drops down a little cooler.

To keep dust out the fan should always blow air in to the darkroom - you want positive pressure.

If the inlet air is well filtered the effect of a positive pressure is to blow the dust out of the darkroom along with the excess air.

You need to keep the fan blowing all the time to keep the darkroom dust free. Dust is drawn back into the room if it breathes with changes in temperature and barometric pressure. Counter-acting the breathing doesn't require much positive pressure: a small muffin fan (you can rip one out of an old PC XT power supply) will do the job if the vents are closed. A bit of thin plastic sheet over a hole between inside and outside air can be used as a check that the darkroom is pressurized - make sure it always bulges to the outside air. It is a good idea to check the room stays pressurized in high outdoor wind conditions.

The best filter for the inlet air is one of the 3M or AprilAire fine particle filters.

I keep my house at 60F in the winter. To keep the developer at 68F I use a heating pad under the developer tray. I put ensolite insulating foam between the heating pad and the bench so the pad doesn't waste its effectiveness heating the bench along with the developer.