Lochinvar 1.5, 3.5, 2.5 service manual Service, K Pumps

Models: 3.5 2.5 1.5

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K: Pumps

1 Service

Minimum Next On Time

In order to reduce the risk of temperature overshoot with a Cascade, this parameter defines the minimum time delay from starting one unit until the next unit may be started. The installer can adjust this time delay by accessing parameter J8.

Rate % to Switch on Next Boiler

When the Cascade is programmed in the Efficiency Optimization Mode, the currently running boilers must ramp up to a certain firing rate before the next boiler in the Cascade will start. This percentage can be adjusted by accessing parameter J9.

Rate % to Switch off Last Boiler

When the Cascade is programmed in the Efficiency Optimization Mode, the currently running boiler will stop. This percentage can be adjusted by accessing parameter J10.

Number of Boiler Pumps Always On

When multiple Crest boilers are connected in a Cascade, the SMART TOUCH control can keep a minimum number of the boiler pumps running, regardless of how many of the boilers are firing. This is useful in full flow systems where the system flow is provided by the individual boiler pumps. This number can be adjusted by accessing parameter J11.

K: Pumps

Boiler Pump Delay

The SH pump delay parameter sets the length of time the boiler pump will run after a SH demand has been satisfied. This parameter is adjustable by the installer by accessing parameter K1.

Boiler Pump Anti-Seize Time

If the boiler pump does not run for 24 hours, it will be turned on briefly to prevent it from seizing. The length of time it runs is determined by parameter K2.

Boiler Pump Mode

The SMART TOUCH control is able to control the boiler pump in 3 different ways. The options are as follows:

1.ON with a call for heat, with a constant speed.

2.ON with a call for heat, with a variable speed output.

3.Always OFF (not connected).

The Boiler Pump Mode can be adjusted by accessing parameter K3.

Service Manual

System Pump Mode

The SMART TOUCH control is able to control the system pump in 5 different ways. The options are as follows:

1.ON with a call for heat, with a constant speed.

2.ON with a call for heat, with a variable speed input.

3.Always ON, with a constant speed, except during outdoor shutdown.

4.Always ON, with a variable speed input, except during outdoor shutdown.

5.Always OFF (not connected).

For options 2 and 4, the speed of the system pump is controlled by a separate control system. The System Pump Mode can be adjusted by accessing parameter K4.

System Pump Delay

The system pump delay parameter sets the length of time the system pump (if connected) will run after a SH demand has been satisfied. This parameter is adjustable by the installer by accessing parameter K5.

System Pump Anti-Seize Delay

If the boiler pump does not run for 24 hours, it will be turned on briefly to prevent it from seizing. The length of time it runs is determined by parameter K6.

HWG Pump Delay

The HWG pump delay parameter sets the length of time the HWG pump (if connected) will run after a HWG demand has been satisfied. This parameter is adjustable by the installer by accessing parameter K7.

HWG Pump Anti-Seize Delay

If the boiler pump does not run for 24 hours, it will be turned on briefly to prevent it from seizing. The length of time it runs is determined by parameter K8.

ΔT Set Point

The SMART TOUCH control includes a 0 - 10Vdc output for controlling the speed of a variable speed boiler pump. The speed is regulated in order to, among other things, maintain a minimum delta T across the heat exchanger. This helps reduce the electrical consumption of the boiler pump when the boiler is firing at less than its maximum rate. (This feature is active only when a system supply sensor is installed). This set point can be adjusted by accessing parameter K9.

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Lochinvar 1.5, 3.5, 2.5 service manual Service, K Pumps