If you are used to simple, straight-cool split systems, you know that the low voltage to the outdoor unit is usually VERY simple. In many cases, there's just a Y (contactor power) and a C (common) connected to the outdoor unit. When the condensing unit controls are strictly two-wire low voltage, there is no continuous […]

We all understand that vacuum pump oil is the lifeblood of our vacuum pumps. We know what the function of vacuum pump oil is and how it functions. But how do we apply that knowledge when choosing the oil best suited for our pumps? Many of us simply pick up what’s in the stock room […]

We've seen it before. A tech diagnoses a failed blower relay or board. They leave the blower jumped out by putting a terminal multiplier on the common terminal of the relay/board and connecting the fan speed tap right to power. There can be an issue with that. Some electric heat fan coils have a heat/blower […]