McDonnell & Miller Series PSE Probe Type LWCOs
Series PSE-800 probe-type LWCO use patented technology to monitor changes in water conductivity. When defined parameters are exceeded, the PSE-800 decides to shut the burner off based on the volatility/variability of the resistance readings. This patented technology provides the best protection without turning off the boiler unless a low water condition exists. As an added safety measure, the control will turn off the boiler if it recognizes an out-of-water condition when the sensitivity threshold is exceeded.
Features:
- Green power is on indicating LED
- Red low water indicating LED
- 30 second DOM
- Test button
- Self-Cleaning probe
- No lockout with loss of power if the probe is in water
- Provisions to add water feeder of alarm
- Models available with:
- 120 VAC
- 24 VAC (meets ANSIZ21.13a specification)
- ‘U’ probe (extended barrel)
- ‘FIX2′ probe (remote)
McDonnell & Miller Series PSE-800-M Probe-Type LWCOs
The Series PSE-800-M Manual Reset LWCO is used as the secondary LWCO on steam boilers and can be used as the primary LWCO on hot water heating boilers. A self-cleaning probe, available only on McDonnell & Miller probe-type controls, reduces probe maintenance to once every five years instead of annually. In addition, manual reset models meet the requirements of ASME Standard CSD-1.
Features:
- Lockout delay
- CSD-1 code compliance
- Power interruption
- Test button
- “Green” power on and “Red” LWCO LEDs
McDonnell & Miller Series 750 and 751P/752P Low Water Cut-Offs
Series 751P/752P probe-type LWCOs protect against low water conditions for commercial and industrial applications. These controls are fully CSD-1 compliant and are primarily used as LWCOs on hot water heating boilers.
Features:
- 120V/24V models available
- Green LED indicates power on
- Red LED indicates low water
- Test button
- Meets requirements of ASME Standards CSD-1
- No lockout with loss of power if the probe is in water
- 20,000 ohms probe sensitivity
McDonnell & Miller RB-24E Low Water Cut-Offs
McDonnell & Miller’s RB-24E patented self-cleaning probe minimizes scale build-up and extends the recommended cleaning interval to five years.
Features:
- Brass threads provide a metal-to-metal seal that ensures a leak-free installation
- Integrated wrench flats enable secure installation without damage to the housing
- “Plug & Play” wiring harnesses are available for most residential gas-burning boilers
McDonnell & Miller RB-122-E – Low Water Cut-Off
RB-122-E LWCOs are for residential and commercial applications.
Features:
- Electronic operation
- Easy to install and wire
- Red low water indicating LED
- Green power indicating LED
- Test button
- Automatic reset
- No blow down required
- 20,000 ohms probe sensitivity
- Maximum ambient temperature: 120°F (49°C)
- Maximum water temperature: 250°F (121°C)
- Maximum water pressure: 160 psi (11.2 kg/cm2)
