Giving the price of a loading valve. What are the advantages of a loading valve over a thermic mixing valve like a danfoss or caleffi ?
Huff
Huff
I have a danfoss. one advantage to some people with a loading unit is it only takes one pass of the water to heat it to final temperature where with a thermostatic valve water may pass threw the boiler two or three times before reaching final temp. this is a non issue for me due to low heat emitters. I often only heat my water to 170 or so especially with the warm winter we are having.
I don't think that's the case for my Caleffi 280 ThermoMix.I would also like to know if any of the separate mixing valves allow for convection flow in a power outage.
I'm not so sure about that - would likely depend on the boiler. I have an LK810 loading unit, and I get 15-25° dT through the boiler depending how I load it & with what kind of wood, pump on speed 1. So it takes two passes to get my storage hot, if starting from depleted.
It works really well, is an easier & cleaner install, and allows for convection flow in an outage. But, it is more expensive, and after my sticking pump issue on startup this fall, I am not sure on the overall servicability of the pump unit. It is a Grundfos 15-58 3 speed pump body (painted gray instead of red), but I don't know if it can be swapped out for an ordinary 15-58 or not if you have bigger pump troubles & need a quick fix, or if it is an application-specific variant of a 15-58. I didn't investigate that - and likely would advise someone to check it out if considering buying one. At least with separate mixer & pump, you have things more modular & maybe easier to fix if something goes wrong - 15-58 pumps are everywhere, and if you keep a spare thermostatic element, you should be able to fix whatever needs fixing quick & easy with the valve. I would also like to know if any of the separate mixing valves allow for convection flow in a power outage. You might be able to get around that if needed & wanted by plumbing in a bypass line that bypasses pump & valve, that has a NO zone valve in it, maybe wired to the same circuit as a NO zone valve on a dump zone.
If anyone knows if an ordinary 15-58 pump body can be swapped into an LK810 in a hurry situation - I'm really curious.
I'm not so sure about that - would likely depend on the boiler. I have an LK810 loading unit, and I get 15-25° dT through the boiler depending how I load it & with what kind of wood, pump on speed 1. So it takes two passes to get my storage hot, if starting from depleted.