I have a customer requesting a proposal for controls to ventilate an indoor swimming pool. This is, as you can suspect, a very humid room (although a little extra humidity is probably welcome whtn you are in a bathing suit!), with tendencies to be quite warm/cold due to the glass ceiling. There is an Engineered Air Makeup unit with an uncontrolled fully open damper for return air from the conditioned space (this damper has never had a motor so far as I could tell). It has a motorized fresh air damper for mixing return & fresh air (gears broken when I checked it). There is a separate ceiling exhauster which is not interlocked with the Eng Air Unit. The Eng Air unit has no cooling (Canada, eh!) and 5 stages of electric heat. There are a couple of line voltage humidistats (Honeywell SPDT type) and a thermostat for the space. One humidistat has no wires going to it and the both are ancient and in need of replacement. The roof is entirely glass, sloped, and facing north (probably partly why the designers figured they could get away without cooling). Winter design temps around here are about -10 deg F and summer 90F dry bulb & 76 to 78 wet bulb. When I arrived on the site the room smelled like a sewer due to the fact that the makeup air fan was down with a blown fuse and the exhaust fan was going flat out, no doubt assisting in evaporating the water out of the traps in the pool deck floor drains! I got the fan running and cracked the FA damper so at least the room can have some ventilation/pressurization & then had to go on another call. I thought of some comparative enthalpy or humidity stuff to control the fresh air dampers, some interlocking with the exhauster, trap seal primers (if possible!), and some needed upgrades/repairs to the heating stager (old one is one of those ancient cam type units with no cover or model number anywhere to be found--in fact no wiring diagrams or unit model numbers to be found either!).