The RD200 Advanced Series heating controls provides optimum energy efficiency for multiple, more-complicated boiler systems. Some boilers require full-modulation control, while others operate using Lo-Hi-Lo scheme, aside from the usual ON/OFF boiler systems in small buildings.
For multiple-boiler systems, when the number of boiler stages reaches 4, model NR203-4 will be required. Models CB200 -D4, -D8 operate up to eight on/off or four lo/hi/lo stages. Models CB200 -B4 and -B8 operate up to four full modulating boilers.
The CB200 hot water series controls offer multi-stage PID control. Based upon how fast water temperature is rising, the CB200 will self adjust a time delay that prevents an additional boiler stage from prematurely firing. PID control is especially cost effective when controlling large water content boilers. Instead of firing a second boiler, and having to double the stand-by losses, the CB200 series waits five, ten, or maybe thirty minutes for the first boiler to “catch up”, saving incredible amounts of fuel and money.
Heating systems with 3-way mixing valves are usually found only in Hi-Rise buildings. The boiler and the mixing valves may be controlled separately. The CB200 D or CB200 B can operate the boiler, or a hot water to hot water, or steam to hot water heat exchanger. These systems require the knowledge of a good heating contractor in order to retrofit with new controls.
The RF207 –ZW has been designed using new wireless technology to control 3-way mixing valves. There can be (3) zones with (4) sensor per zone, or (4) zones with (3) sensors per zone. The RF207 -ZW calculates the average of wireless remote space temperature sensors placed within each zone. The mixing valve actuators must be of the “floating” type and receive pulses from the RF207 -ZW, which slowly adjusts the mixing valves to actual room temperatures within each zone. No outdoor reset control can match the fuel savings obtained by sensing actual indoor zone temperatures.
The CB200 –E, and –G series controls are used when constant steam pressure is require from single or multiple boilers. Up to 8 on/off, 4 lo/hi/lo or 4 full modulating steam boilers may be operated. The –E series operates multiple full modulating steam boilers, and the –G series operates multiple lo/hi/lo and on/off steam boilers.
The RF207 -ZS senses room temperatures from wireless remote space temperature sensors. There may be (3) zones with (4) sensor per zone, or (4) zones with (3) sensors per zone. The RF207 -ZS calculates the average of the wireless sensors within in each zone. The ON/OFF steam zone valves are controlled by (4) relay outputs, one for each zone.
This application is common among older churches. In the past, a single thermostat controlled steam zone valves, there was no night setback and the installation was costly and difficult. Thermostats were scattered all over the church, and each steam zone had one point of control, which is unreliable and inefficient. As a bonus, the RF207 –ZS operates the steam boiler only if one or more zones are calling for heat. The entire system operates on actual indoor room temperatures saving thousands of dollars in energy costs.
RF207 Product Manual
CB200 (for Full Modulating Burners) Product Manual
CB200 (for ON/OFF and LO-HI-LO Burners) Product Manual
NR203 (HW Outdoor Reset Only) Product Manual
NR203 (HW Outdoor Reset with Learning Software) Product Manual