Your hired bring your lunch.
Are they freestanding cast iron radiators or baseboard radiators? If they are freestanding then there not a loop system and can't be purged. They...
That's your problem. You need a pressure tank connected to the system.
Where is the pressure tank located?
I would add putting a large hose clamp around the fitting applying the ABS cement.
Replace the cartridge on the tub faucet.
I would return the tub.
That is a tempering valve installed on the heater that mixes cold water with the hot.
I'm telling you it is grease. Pout some grease out of a frying pan into a container and let it set for a day or two and it will look and feel that...
That is definitely kitchen grease I have seen it many times
That is grease.
What he is asking is if the larger pipe would increase the volume, which it well but it will not increase the pressure.
From what I'm seeing it's not connected to a waste line it's just dumping into the crawl space.
With it piped to the crawl space there is no way you would be aware there is a problem with the heater.
That looks like the shower base is cracked.
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