I was a little nervous but I did it!! I hope it's right-;). Here's a pic of the old filter. I had a bit of trouble turning off the saddle valve as the handle was tight. And also, the tube stayed on the tray when I took the whole thing out. So I just took the old water panel out and slipped the new one in with the mark on top and snapped it back on. I went back downstairs to put the thermostat up so it would be running but when I did, it said waiting. Was it trying to reset itself from the furnace being shut off? I will try it again soon. Also, I bought one of those humidity monitors-;). Thanks again, Rainey

SR Thanks for the input. I have decided to add the expansion tank which i will connect to the 1" purge cart pipe on the return side of the system so I pump away from it. I found a nice potable water tank at www.blueridgecompany.com. It is a B&G tank with 10 gallon capacity - costs under $150 shipped. When I add the tank, I will also be adding an air separator near it. I am aslo adding a permanent pressure gauge so that finally I will have indication that the loop field is working. Based on your advise, when i add the water line to allow easier juicing I will only open the valve when I need to add water and then shut it off. Even though I have a backflow device rated to 200 psi for the new line, no need to risk contaminating my water supply no matter how low the risk. Since I have been manually juicing and checking pressure over the last month to make sure I am at or above 40psi, I found a tiny leak at the connections to the primary loop pump. This is why my system has not been holding pressure - I loose about 1/8th to 1/4 of a cup per day when the system is charged. I suspect that the leak slows down when the pressure drops which is why I haven't noticed it. The whole house dehumidifer that is close by is drying the little puddle before I see it pooled - I thought it was condensation dripping it was that slow of a leak. Once I fix the leak I shouldn't need to juice the system unless I get some air bubbles. There is no real technical issue about having a unit on the second floor as long as the lines are well insulated and the anti freeze level is correct. However, after all this I have had time to think about what might happen if I developed a big leak up there - it wouldn't be pretty. In fact any major leak inside the house would be horrible. If the loop pump came on and I wasn't home to catch it - I could have many many gallons of methanol water dumped into my house. So I have decided to add a low pressure switch onto my system near the expansion tank. I found a pressure switch with a 1/4 npt fitting that accepts a low voltage AC input and has Normally Open and and Normally Closed contacts. I can add the switch in series to my loop pump control circuit which is 24 VAC driven . The pressure sensor can be adjusted for low pressure down to 4 psi. If I sense that the pressure drops - say below 25 psi, I can automatically shut off the loop pump. I might add a few idiot lights to this new circuit so I can see a green light for good pressure, red light for bad. These mods should make the system work consistently in summer & winter, provide me a way to tell the loop field is working right, and provide a simple failsafe for a broken loop line. If I were doing it all over again, these would have been mandatory functions when the system was first installed. Thanks for the help.

Got an additional quote for Lennox equipment, it seems to be what most around me are spec'ing. Price-wise, it's the best I've seen and I trust their ability to install the equipment based on reputation and referrals. Based on the conversation here and pricing it all out, I'm going the high efficiency route. That said, can someone clarify the difference between a "ECM Multiple Speed Blower" (spec'd with EL195UH0707XE36B) and "2-stage Furnace Variable Speed Blower" (spec'd with EL296UH070XV36)? @tigerdunes, is the "ECM Multiple Speed Blower" a high efficiency blower motor like you've been recommending? Guy gave me three quotes, strongly considering going with option 1. Options below. Option 1: One Lennox Model EL195UH070XE36B 95% Furnace ECM Multiple Speed Blower $ 2,500.00 Option 2: Replace furnace using ML195UH070XP36B Standard Multiple Speed Blower $2,170.00 Note: Either furnace above qualifies for a $150.00 Federal Tax Credit Option 3: One Lennox Model EL296UH070XV36 2-Stage Furnace Variable Speed Blower $3,390.00 Note: The above furnace qualifies for a $200.00 Federal Tax Credit Note: The above furnace qualifies for a $100.00 Factory mail-in rebate Any of the above options include: - Honeywell Model Pro 6000 (I already have a Honeywell Vision Pro 8000, so this is a moot point) - Air Bear Filter Mounted in Fabricated Housing - Chimney liner for water heater $425 Any additional thoughts? Thanks again, guys.

Thank you rweigand - I will check and also try to get some photos of the setup. The filter was replaced just a few days ago. Do you reckon having humidity meters on each floor is a good idea? PS: We're in Massachusetts. The weather has been all over the place in recent days. Its rainy and 11C today and tomorrow, and then dry and 21C on Thursday! Hows that for xmas eve? Never thought I'd see that kind of temperature for xmas! mike_home - There is no doubt we have air leakage issues. We have drafty windows (and it is a very old house anyway) that will be replaced in the 2nd week of January and then insulation will be blown in to the external walls on 19-20th of January by a MassSave contractor. Should we wait it out to see what changes the windows and insulation will bring before blaming the HVAC system for all our humidity woes?