7

Since hot rises, upper stories will tend to be warmer unless the design of your air conditioning system properly compensates for it. An energy audit, as mentioned in the comments by @mikes will tell you if you have any reasons for heat gain that may be correctable. Assuming you have a single thermostat that controls a unit that supplies both levels, here ...


6

Yes. I was building a new home in Baytown Texas (completed in 2006) and searched far and wide for thermostat controlled dampers - was told by many HVAC companies that "they" remove them weekly - this isn't true. I found one installer in Houston that would do the system the way I suggested - he listened and so did I. We compromised on 2 units with 3 ...


5

If you only have access to the inside of the duct, and then only as far as you can reach, you won't be able to make a huge difference, but you might be able to reduce it a little. The sound is transmitted in mainly two ways, some is conducted through the metal of the duct and some is reflected around the inside of the duct until it reaches you. You can ...


5

The reason furnaces (as opposed to heat pumps) keep running is to cool them back off since the burner is pretty hot. It may be a safety issue (too much undistributed heat could make the furnace hot to the touch and possibly result in a fire), but I suspect it's also done to extend the life of the furnace from large temperature swings with the side benefit of ...


5

Empirical Engineering Answers: Yes: you will save electricity costs by running your blower on low. No: you will not save on gas/oil costs by running your blower on low. Because the slower air velocity over the heat element is transferring fewer BTU units into the circulated air and they simply go up the exhaust pipe. The NET difference of the above two ...


4

If the furnace manufacturer supplies different burners for that unit you may be risking premature failure. The heat exchanger can be overheated and burned out if the blower does not remove enough heat. Proper duct sizing can resolve the issue you are having. Sometimes you have to add more ducts to achieve the proper pressure and velocity.


4

If partially closing a single supply vent caused your high limit to trip you probably have an restriction problem. I would recommend investigating a bypass damper with a return and supply temp. sensor. These devices are typically just a part of a whole house zoning system, but can be used to easily resolve supply air restrictions in situations where ...


4

The reason that 90 degree turns (or any tight radius bends) in duct systems are discouraged are because they reduce air-flow. The friction that is encountered by the moving air as it hits the wall of the turn slows it down decreasing the distance it can travel. There are equations that can be used to calculate the number of bends before air performance is ...


4

I would use drywall compound and fill in between the wall and the duct. And then I would tape using a UL181 tape (I like foil mastic) over the inside edge of the duct and the wall. Apply the tape flat and rub it smooth. The tape will be covered by the register. Using UL181 tape to seal the duct to the ceiling membrane really should be standard.


3

It'll work well as long as your mini split unit isn't conditioning the area near the thermostat for the forced hot air unit. If they're too close together, the mini split will make the forced air thermostat think it's always the perfect temperature, so it will never call for heat, and the rest of your rooms will never be comfortable. The added expense of ...


3

Cut the gas back some by slightly closing the gas valve (the one on the pipe, not in the unit), however be prepared to have to reset the furnace occasionally if your local gas pressure drops intermittently. Watch the flames as you do it. Just, "take the edge off". This will cost you more in electricity, as it'll run longer to come up to temp, but it will ...


2

You can't. I have the same problem. My house has a 125,000 BTU furnace for a 25,000 BTU heat load. My solution? I set the thermostat at 69 and turn it on manually when the temperature falls below 65 or so. This ensures that the furnace runs for a nice long time when it's on, and then stays off the rest of the time. But you don't really even need to do this ...


2

I know this is an old post, but thought I could help future visits. My house is about 1900sf and my furnace is a 135k BTU (a bit much). In my case I had a cracked heat exchanger and the crack was very close to the high limit switch, which of course kept shutting the unit off. I also found that the inside of the a-coil was very dirty/if not partially clogged. ...


2

First off, check how many wires are connected in your stat. There should be 2. If so use a tester set to volts AC. Test for power, you should get 24ish volts across the two wires (usually .W and R or Rh). If you get 0 or 120 you have a different issue comment back and I'll edit the answer. So 24v at the stat; jumper W and the R/Rh with a small peice of ...


2

I'm currently storing 9 240VAC 500 watt radiant (or infrared) panels; not sure if I'll use them or not, but they certainly exist in the US market. Mine were taken out and replaced with an oil-fired boiler as a less expensive source of heat. The space they were in had at least a 10 ft ceiling and they were ceiling-mounted, and quite effective, just expensive ...


1

You do want your return larger this will not be a problem and allows room to install it then sheet metal or a flexible seal can be added. If things are two close it makes it tough to sweat the fittings


1

I will second the thought of putting in 18 awg wire to the thermostat. From your picture, it is difficult to correctly identify the terminals. The best option is to download the furnace manual off the internet for the model you have. Just to verify exactly what each terminal is.


1

You'll want to pull a new cable The installer who put the existing programmable thermostat in didn't pull the correct kind of cable -- they grabbed a spool of network cable and used that instead. Problem is, network cables use much thinner gauge wire than thermostat cables (22-24AWG for network cabling, 18AWG for thermostat wire), which means that the ...


1

A good duct-sealer with fibers can be applied thickly with an old paintbrush. It also strengthens tape that covers gaps. If needed, a metal patch can be screwed on from the outside, then duct-sealed. If you want you can add duct-seal to the back of the patch, but the thick product forms a membrane on top of almost anything. Give it 6 hours to dry before ...


1

I've used duct sealer in the past to seal up my attic air handler, it applies like a paste and dries hard. You can try that, but you options of globbing it on may be limited. Is this duct in a basement or crawlspace? The handler and ducts in my unfinished basement leak a bit, but I don't bother sealing them up as it helps keep the temp in the basement ...


1

Mercury thermostats are VERY accurate and last forever. Either it is now not level, or the heat anticipator is mis adjusted or not making good contact. If set at 65 degrees, the furnace should kick on at 64 and shut off at 66. If the swing is wider than that, the heat anticipator needs to be moved towards shorter. My Honeywell mercury thermostat is 65 years ...


1

The W2 (Aux/E) terminal on the thermostat is for a second stage heat relay or heat pump auxiliary / emergency heat. Note that this is to energize a relay or contactor coil, which will in turn energize your baseboard heaters; you can't directly switch baseboard heat with the Honeywell 9000. Selecting a contactor or contactors and rewiring your ...


1

Been there, done that. That pan is called the secondary drip pan, and must be larger than the unit on all sides. It should be open, and it should have either a drain that driips in an obvious place, like the center of the garage so you can be annoid by it and get it fixed. If it has no drain, it should have an float switch that either triggers an alarm or ...


1

I would maintain a hot water heating system for the increased comfort. Forced air is actually quite uncomfortable to people but it is cheap to install. Just google "ideal heating curve" and you will see the many graphs comparing different types of heating systems. Like here. And here. So you can choose, save money now and suffer or spend more now and be ...


1

I solve it slightly different way, using Macromatic TR-6512U repeat cycle relay. This relay has independent ON time and OFF time settings from 5Sec. to 100 Hrs. It is very important that relay is ON First. It works on any voltage from 24V-240VAC. My thermostat drives the relay and contacts turns on gas valve. I observed my Hi limit first it usually took ...


1

Try this website: http://www.theactivent.com/ The wireless controlled vent cover costs $35 (may need multiple per room), the wireless temperature sensor (one per room) $30, both together cost $50.


1

Similar to Mazura's second answer, the Ductwork from the from the return can and should be really long. If you have the room where the ductwork for the return is, make it really long and zigzag it. Mine could be a Direct shot of 10', though I think they installed over 30' of ductwork and it curves all around the place. You can detach it from either end, ...


1

Fiberglass Duct Liner: (industrialinsulation.com) Fiberglass duct liner is designed to be installed inside sheet metal ductwork and plenums. Fiberglass duct liner absorbs noise and contributes to indoor comfort by lowering heat loss or gain through duct walls. Or if you have the space for it, build some baffles out of 2x4' acoustic ceiling tiles inside ...


1

It definitely sounds like that section of duct has a leak or travels through an un-insulated part of the structure. Sometimes the cavities between walls or under floor joists are used as duct or returns and they are not enclosed. Leaks in the building envelope, especially with such cold weather, could keep that area cold all the time and any warm air blowing ...


1

A lot of good suggestions were given, but in my case it ultimately was two things: Poor insulation - the energy audit found the insulation was about 8 to 10 inches too low for our area. Given the age of the house, it wasn't surprising that this needed to be rectified. Soffit vents - or lack thereof. I had no soffit vents to ventilate the attic properly. ...


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