Quick connect or sharkbite shutoff valves

[huedat]

So I successfully replaced an old gate valve and sweated on a new ball valve on one of my zones. At first, I tried to remove it by un-sweating it, but it was impossible because the residual water in the system, so I cut it and sweated on the new valve.

Unfortunately, I have feeling when I refilled the system and and used the other old gate valve to zone the system and purge it, they too showed micro-leaks along the stem.

So I thought about using watts quick connect( similar to sharkbite) valves because it was bit of pain to sweat the valves (weird layout).

I looked at the specs for watts quick connect valves and the max temperature is 180 F at 200psi.

My boiler aquastat is set at 185 F and operates at 15-20psi. Can I still use this fitting?

 

[Terry]

I see failing rubber washers already on the hot side of water heaters. Can you snug the bonnet nut or repack it?

 

[Sponsor]

 

[huedat]

I had a sinking feeling about the reliability of those type of fittings because I was planning on replacing the water heater soon, too. Repacking is an option, but I'll suck it up and sweat new valves, they're pretty crusty looking from the minerals left behind.

I've had to replace the pump cartridge twice because the pressure in the system would drop and cause premature failure.

Thanks

 

[Terry]

I sometimes take a saw blade and cut the valve on the low side to drain the water out. And/or use a shop vac to suck as much out as you can. But yes, any water there will prevent you from heating and removing it.
And when soldering, you need to leave something open, or the steam and heated air blows a hole in the new solder joint.

 

[Dana]

A somewhat orthogonal issue, but very few residential systems need anywhere near 185F out of the boiler (or even 180F) even when it's -20F outside. Is it cranked up that high because it has an internal tankless coil for domestic hot water and doesn't cut it at some lower temp?

 

[huedat]

I thought 180F was the average?

 

[Dana]

I thought 180F was the average?

180F was a common system design temperature in 1950 when houses were barely insulated and clear glass storms over single panes were considered really great, and the systems were oversized by 2x even for the heat load then. Even that house from 1950 has more insulation and probably better windows and better air tightness, but the same radiation and too often the same boiler (or the same boiler size.) Most older homes that have undergone a few rounds of building efficiency can now cover the load at the 99% outside design temperature with 140F-150F boiler output.

Unless you know it takes 180F to stay warm or to keep the boiler from short-cycling on insufficient radiation for the size of the burner a lower temps, there are both comfort & efficiency benefits to turning down the temperature. This can be achieved with an outdoor reset controller (at some risk of short-cycling), or with a heat purging economizer (which will minimizes the number of burns and the average boiler temp, but not necessarily the peak boiler temp.) But idling it a at 185F when there's no or low call for heat is a waste, even if it might need to be than high when it's -25F outside to get that much heat out of the existing radiation.