Honeywell TrueSTEAM HM512 Homeowner's Manual page 21

Changing the reverse osmosis filter cartridges. If the reverse osmosis filter is used in your
installation, you will need to replace two filter cartridges once every humidification season. Notice that the
reverse osmosis filter option has more components than the in-line filter and includes a separate drain line.
This option _rovides better filtration and prevents harder water from flowing into yOUr TrueSTEAM.
Remove filters #1, #2, and #3, in this order.
Reconnect filters in this order:
• Empty water from the #3 filter and reconnect to the
RO System. (Do not replace.)
• Connect a new #2 filter.
• Connect a new #1 filter.
M29663
2O TrueSTEAM Humidification System 69-2286EF--01