Haven't been on here for a few years, but I still like to read different posts every now and then.
We sold our previous home and and have since moved into a ranch home. The home has 1162 sq. ft, a basement with approximately 1200 sq ft and a garage with approximately 568 sq ft. All three spaces are heated with copper fin baseboard. I am going to work on tightening the place up, since nothing was really updated, other than the windows (double insulated) and the front door.
The first problem I encountered was that there was a constant drop of water from the bottom of the expansion tank. When the system started up all you would here was a constant gurgling, waterfall, dripping water in the baseboard. I knew there was air in the system after dealing with the heating system in my previous house. Apparently, after the previous owner neglected the heating system for what I assume was years I decided to get to the bottom of the dripping to correct the air problem. I found that the Taco air scoop was so corroded from the inside, from all the air in the system, who knows for how long, that it had a pinhole causing water to leak onto the expansion tank and off the bottom. I replaced the expansion tank and the scoop, but not ever dealing with a diaphragm one, neglected to make sure the pressure was equal to the supply pressure. After many attempts to purge all the air from the system, I finally researched enough to get all the air out and have the system working totally air free. This was all done about 2 weeks ago, so mind you, I just needed it to be working as to not be left without heating for a prolonged period. I believe the pressure is too high, since it is a ranch and I think the pressure should just be around 12 psi. I think the electronic tire pressure gauge I used to set the expansion tank pressure was not too accurate, but it's all I had. Plus, I want to avoid draining the system again since it has no isolation valves to help with servicing the system. I also changed all the only manual air valves to auto air vent ones.
I know that the ideal way to install the air scoop was to have it behind the pump, but the timing to get this done is not the best right now, so I will get this squared away after this winter season. I would like to get all the work done at one time and avoid having to drain the system and have something major go wrong and be left with no heat.
A few question:
1. I really like the way the monoflo system delivers heated water to virtually every baseboard at the same time, so what can I do to make the system more efficient? I was thinking of buying a Delta T pump to get the most out of every heating cycle.
2. I would like to create a 3 zone system with the existing monoflo one in place. By this I mean making the 3 heated spaces described above into their own zones. Can this be done?
3. i would like to keep the Vaillant for now because it seems to be working without any problems, but would it be wise to change to a High Efficiency Boiler even a Combi one? I ask about the Combi because the gas water heater was installed back in 2005 at this house and I know it might be on it's way out soon.
All input and advice is greatly appreciated!