Best Of
Re: Old HP system failed: new refrigerant choice? new equipment reliability?
This is the wrong time to buy. It seems reliability and the new equipment and new refrigerants are not very compatible right now. If I was going to make a choice I might buy Goodman. Last I knew they were R-32 and do not use the ill fated microchannel coils. In the past they (Goodman) had a reputation of being cheap crap. Now everything is expensive crap
Re: Who owns who?
It's getting like car batteries. 1000 brands but there is only 2 or 3 MFGs.
Re: Its on every plumbing exam.......
We call them LPTY Long Pattern Tee Wye or Combination Wye and 1/8

Trouble on the Roof
One of my customers here in Berkeley called me that his carbon monoxide alarm was alerting him to high levels of CO in the mechanical room . I picked up ~500ppm at the boiler with my analyzer, but wondered how it was getting into the house.
After shutting down the boiler, the owner told me that he had a new roof done in January and when I checked the termination, the new top had been pushed down so far as to almost completely block the flue.
I see this often enough.
Re: Help! Pressure keeps rising on Weil McClain Eco 70 system
The only way cold pressure can build is water getting in from a higher pressure source. If there is no domestic hot water coil or indirect hot water heater — it' the fill valve.
Re: Combining supply lines to manifolds?
If you total max flow is 5.5gpm use 1" with a tee for both manifolds
3/4 is good for 4 gpm
1" is good for 8gpm