Do you have an expansion tank? And do you have a Pressure Reducing Valve (PRV). Both the tanks and the valves often give out after about 10 years. I started getting weird noises in my water system after my house was about 8 years old. I checked the water pressure downstream of my PRV and it was high, and couldn't be adjusted downward. I got a PRV rebuild kit and was once again able to adjust the pressure. I then checked the expansion tank, and that wasn't functioning properly either, so I replaced it. The result was proper water pressure in the house and no more strange noises. I don't know if this is a fix for you, but it's one possibility.

Again any specifics I suggest without studying the layout in person would be near worthless. There should be several contractors with time on their hands right now,give one a call and ask him to come out. Ordinarly i avoid roof penitrations (esp flat ) like the plauge. Sometimes you have no choice but it's usually due to something other than economizing on ducts where evap cooling is the system under consideration. Understand we get little experience with evap cooling in Tx but I've seen several places in SW resort properties useing multiple units. I geathered that units and labor to install don't add up much faster than ductwork and install. Evap doesn't demand highly effecient return air like other types. In fact I've observed places where air flowed outdoors to a porch,sitting area or plant growing inclosure to relieve postive pressure. Hopfully someone more familar will chime in with ideas you can use.

Snookums, The electric ones have come a long way too. They are also cheaper than the gas units so you could do multiples. There are a few things which will make tankless more successful for people. One is understanding the flow rates of your water using devices. I have low flow shower heads and in one of three bathrooms, I have a thermostatic valve. The other two bathrooms are getting upgraded to Thermostatic valves. This allows you to set the temperature of the shower and not have effects like cold water sandwiches where the heater is struggling to produce hot water. I have never experienced this issue. My Washer and Dishwasher are also low water use appliances and heat their own water. This limits the load on the water heater to just hot water demands at the faucet and bathtubs. Also, getting a scale filter and a whole house water filter if you have hard water will lengthen the life of your tankless unit. Good luck!

First, review your contract with the GC and read the section about terminating the contract, then reread it a couple more times. Make sure you understand what you have signed. Even if I expected to fire the contractor, I would not start the conversation going that direction. I would ask a few very open ended questions and see where the conversation went from there. Your contractor may have any or several of a multitude of reasons why his performance isn't up to par. If it doesn't seem like his heart is in the job, ask him whether he wants to continue with the project. He might be upset with the question, in which case he will be even more upset when you tell him you are firing him. Or, he might be relieved that you are willing to let him out of his commitments. If that's the case, you may be able to negotiate a smooth exit more cheaply than if you just abruptly pull the plug. Rules vary in different states and even from crossing municipal boundary lines so I don't know whether he is allowed to do the work himself. Just because he preferred to have a plumber do the work does not necessarily mean that he is not capable. He might be too busy, might not enjoy that work, might be good at it but very slow, maybe might just hate plumbing because he's spent years doing it and is ready to do anything else...