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Is running a system backwards a problem?
I finally found a competent heating guy in Santa Fe!! Of course he's not from New Mexico. Anyway, I asked him to confirm that my system was installed backwards and he confirmed that it was indeed completely backwards from the boiler manufacturer's instructions. Attached is a diagram from the manufacturer of the boiler.
The system is a LAARS MiniTherm II 125JVT for radiant floor heat in a slab.
My system piping is closer to the diagram on the right even though I have Entran III which requires a lower water temperature. At any rate, the system (while not exactly the way the diagrams show it) is plumbed exactly the opposite of the diagram. The single circulator in my system pumps out of the boiler and the zone valves are on the supply side of the plumbing. There is no secondary zone circulator (which might explain why the far zones do not work well).
While the house is warm enough, I keep having to replace parts that are failing, especially Honeywell zone valves. The new NATE certified tech thinks the valves are failing because of too small a transformer (I replaced that with a bigger one after discussion on a separate question on the Wall) but also because the system is backwards and it is putting too much strain on the valve motors.
Question: How big a deal is it if a system is installed backwards from the boiler installation instructions?
Mike - Los Alamos National Laboratory
Not a scientist -Just a nuclear garbage man