Lochinvar KNIGHT 800 - Manual (Page 5)

Installation & Operation Manual
Front View - Model 399
4
5
25
30
23
20
28
13
29
14
8
7
27
36
Left Side (inside unit) - Model 399
19
21
16
1
3
34
17
26
2
37
Right Side (inside unit) - Model 399
The Knight XL - How it works...
(continued)
Rear View - Model 399
5
Model 399
10
24
32
18
11
6
15
33
22
31
36. Air pressure switch
The air pressure switch detects blocked flue/inlet conditions.
37. Pump relay board
The pump relay board is used to connect the boiler, system and
DHW pumps.