(Part 2) Best hvac controls according to redditors

Hmm...

The Beacon Morris unit is a good idea as the vent will really increase the heat transfer considering the relatively low temperatures out of your water heater.

Two things to keep in mind: your hot water heater (I'm assuming you aren't talking about a water boiler for a house hydronic heating system) wasn't designed with re-circulation in mind. The heating unit wasn't designed with potable water in mind.

You'll need a circulator pump, even the smallest one you find will still be massive overkill for your system: http://www.amazon.com/Taco-007-F5-7IFC-Cast-Cartridge-Circulator/dp/B003EV1BAU/ref=sr_1_9?s=kitchen-bath&ie=UTF8&qid=1320530657&sr=1-9

You'll need a thermostat: http://www.amazon.com/Double-Pole-Voltage-Thermostat-21042/dp/B000H5T4X2/ref=sr_1_131?s=hi&ie=UTF8&qid=1320530858&sr=1-131 It's for a baseboard (resistive) load, but it should be oversized enough to run your relatively small blower and tiny circ pump. You'll want both items to cycle on and off together, so wire them all through the thermostat. Extremely simple, like this:

120VAC Hot > one side of thermostat > (internal thermostat automatic switch) > other side of thermostat > wire running to hot side of both pump and fan

120VAC Neutral > wire running to neutral of both pump and fan.

You don't need any kind of automated valving, it wouldn't do anything the pump doesn't also do.

When the pump runs, it's going to lower the pressure on the outlet side of your hot water pump (no idea how much), and increase the pressure on your inlet side (again, not even a clue). Hot water is going to come out of the heater, lose a bit of temperature, and go into the cold side of the heater to be re-heated. The fan is going to force more air over your heat exchanger, effectively increasing it's size. The thermostat will automate the whole thing, turning it on and off as your setting dictates.

That all said, I don't recommend this off of a residential hot water heater. If you had a water boiler servicing your household space heating needs, it'd be a no-brainer. 700 square feet? Get a small electric space heater and wear warm clothes when it can't keep up...

Alright, so far, I've got:

• Shrink wrap on the windows
  
• Door sweep on my entrance to the apt hallway (I could actually feel a breeze here before, crazy.)
  
• Foam tape on the same door frame
  
• Keeping the door between my heated and unheated room shut religiously. The flux in air between the rooms was actually making both feel colder, and I was turning up the heat more in response to this perception.
  
  I am still extremely suspicious of my baseboards (not the heater, the actual trim itself) because I can feel a draft under my desk, but I don't see any physical gaps to stop up. Maybe a piece of fire retardant duct wrap would work to both stop the draft and prevent issues with the heater? (The heater is kept off in this room since it doesn't have an auto-off, but I'm not about to put anything under/around it that's flammable.)
  
  Thank you all for your help!

It's a supco SPP5 kit. I'll find the amazon listing in a moment. It's a simple plastic cap with 2 contacts coming off of it.

EDIT:

Supco SPP5 Hard Start Kit, AC Compressor https://www.amazon.com/dp/B0002YTLEU/ref=cm_sw_r_cp_apa_i_wyLgDbC0JQF1G

You can get a Pro 4000 thermostat, and a matching cover plate. With the plate you will get 8" w x 5.5" h of coverage.

They sell fan delay timers that have integrated circuits inside that will do this for you. They're very easy to wire. You can buy them on Amazon here:
https://www.amazon.com/ICM-Controls-ICM253-seconds-Adjustable/dp/B000E24YQA

Relay, Fan, 208/240 Vac https://www.amazon.com/dp/B000PY7WUM/ref=cm_sw_r_cp_api_i_ju4ODbFYTSCHC

This is why I've started using these controllers. Some faults just can't be recreated while we are on the job. This one will record why it failed and i can go back and check the history.

Johnson Controls Wall Mount Humidity Element with Silicon Temperature Sensor

no meter. I just had the non contact voltage tester (i think its called. hold it near a wire w voltage and it turns red).

The transformer had 4 wires on it. 2 of them (which i would assume were 240 input and com) were energized, 208 input was capped off. The other 2 coming out the other side (24v) seemed dead, no power in those lines.

This was the transformer in user and being replaced:
https://www.amazon.com/gp/product/B00D7MK7GA/