Setup Of Valve Proving Function - Honeywell S7800A1167 Manual

7800 SERIES S7800A1167 KEYBOARD DISPLAY MODULE
• Split—the high pressure test (MV2 seat test) is performed at
the Before time and the low pressure test (MV1 seat test) is
performed during the After.
The Valve Proving items programmed are:
1. Enable Valve Proving and, if so, when to perform it.
2. The time duration of the test is selected from a table
where values and ranges are provided.
Valve Proving Function
Valve proving consists of monitoring the pressure in the space
between two shutoff valves, MV1 (upstream) and MV2
(downstream). The valve proving function, identified by letters
A through G, will operate as follows:
NOTE: The tolerance on all valve proving timing values is
±10%.
Below are steps performed during Valve Proving tests. This
section is for background information and does not define the
exact behavioral requirements.
A. The RM78XX requires the combustion airflow switch (ter-
minal 7) to power the gas valves for testing. The airflow
remains on throughout the Valve Proving Test. RM7890 will
require power on terminal 7.
B. MV2 is commanded to be open while MV1 remains
closed, to depressurize the space. After four seconds, MV2
is commanded closed again.
C. This is followed by a three-second delay during which the
valve proving pressure switch (VPS) is ignored.
D. Thereafter, the VPS is monitored for the duration of the
Valve Proving Test time, and, if it turns on, then a lockout
occurs (because the gas pressure has increased due to a
leaky upstream valve).
E. MV1 is commanded to be open while the MV2 remains
closed, to pressurize the space. After four seconds, MV1 is
commanded closed again.
F. This is followed by a three-second delay, during which the
valve proving pressure switch (VPS) is ignored.
G. Thereafter, the VPS is monitored for the duration of the
Valve Proving Test time, and, if it turns off, then a lockout
occurs (because the gas pressure has decreased due to a
leaky downstream valve).

Setup of Valve Proving Function

Prior to setup of the Valve Proving Function, follow the
procedures in the appendix of the Relay Module to complete
the worksheet and obtain the Valve Proving Test Time.
An S7800A1167 Keyboard Display Module (KDM) is required
for this setup and the RM78XX must have the Valve Proving
function. The device must be in Standby or Alarm to get the
Setup screen.
1. Scroll down until "Setup" is displayed in the second line.
Fig. 101. STANDBy/Setup screen.
65-0311—02
2. Enter the Setup subroutine by pressing the far right key
on the display. Note that the second line now reads "BC
Password".
Fig. 102. Password screen.
3. Use the up/down arrows to enter the first number—7.
4. Use the far right key to shift over one space.
5. Use the up/down arrows to enter the second number 8.
6. Press Enter (far right two buttons).
7. To get to the next screen, press down arrow. "Getting
Data" will be displayed, then the following screen.
Fig. 103. SETUP: Valve Prove screen.
NOTE: This screen sets up when to do the Valve Proving
Test.
8. Use the up/down arrows to select from Never, Before,
After, Both, or Split, then press ENTER.
NOTE: Use Never on initial startup so that System Checkout
can be performed. Then come back to set final
operation configuration followed by the VPS system
checkout.
Fig. 104. Save Changes screen.
9. Use the down arrow to save changes. After pressing the
down arrow, "Getting Data" is displayed.
Fig. 105. Valve Prove time screen.
This screen sets up how long the RM78XX will conduct the
Valve Proving Test for a given time. VP TIme: 00:00 is shown.
10. Enter the appropriate Valve Proving test time from the
worksheet in the RM78XX Instruction Sheet.
Use the up arrow to increase time. Time increases:
a. 0 to 60 seconds in 1-second intervals.
b. 60 to 600 seconds in 10-second intervals.
c. 10 to 60 minutes in 1-minute intervals.
Press ENTER when correct time is displayed.
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