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Head pressure controller - 2 speed fan
Just want someone to double check me on this.
My outdoor unit uses a simple 2 speed fan motor and I'm really considering installing a head pressure controller. Something like the ICM ICM325. Just something I'm mulling over. Ran the unit in test mode this morning when it was 57F out and I'm betting it was underfeeding. Probably still acceptable, but pushing it.
On this setup, my guess is I'm going to only use high speed on the fan and allow the controller to do the rest. The problem being, the PCB switches between high and low. From the schematic, it appears high and low (relays K3 and K4) can simply be connected together and then feed the controller.
The other issue is going to be where to put the controller. I highly doubt I have enough room under the cover on the condensing unit.
Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment