Unit installation

12
Daikin IM 980-1
Installation
3 Fill the system at the city water makeup connection with
all air vents open. After filling, close all air vents.
4 Start the main circulator with the pressure reducing valve
open.
5 Check vents in sequence to bleed off any trapped air,
ensuring circulation through all components of the
system.
6 While circulating water, check and repair any leaks in the
unit and surrounding piping.
7 Drains at the lowest point(s) in the system should be
opened for initial flush and blow-down, making sure city
water fill valves are set to make up water at the same
rate.
8 Check the pressure gauge at pump suction and manually
adjust the makeup to hold the same positive steady
pressure both before and after opening the drain valves.
9 Flush should continue for at least two hours or longer
until the drain water is clean and clear.
10 Shut off the circulator pump and open all drains and
vents to completely drain down the system.
11 Short-circuited supply and return run outs should now be
connected to the unit supply and return connections. Do
not use sealers at the swivel flare connections of hoses.
12 Refill the system with clean water.
13 Test the water using litmus paper for acidity, and treat as
required to leave the water slightly alkaline (pH 7.5 to
8.5).
14 Antifreeze may also be added at this time. Use
commercial grade antifreeze designed for HVAC
systems only. Do not use automotive grade antifreeze.
Antifreeze will have an effect on the performance of the
unit.
15 Once the system has been filled with clean water and
antifreeze (if used), precautions should be taken to
protect the system from dirty water conditions.
Operating Limits
This equipment is designed for indoor installation only.
Sheltered locations such as attics, garages, etc., generally will
not provide sufficient protection against extremes in
temperature and/or humidity, and equipment performance,
reliability, and service life may be adversely affected.
Venting Hydronic Coils
Hydronic coils require a vent, either manual or automatic, to
release air from the unit. Primary coils on all Thinline fan coils
come standard with a coil air vent. It is located on the piping
side of the unit, above the coil connections. See Figure 14.
Secondary coils on ThinLine units are not equipped with an air
vent, but one is included on all factory-supplied valve and
piping packages. It is located on the pipe closest to the outlet
coil connection. See Figure 14.
Perform the following steps to vent both primary and
secondary coils after installing the unit.
1 Pressurize the building piping system with water and
vent any trapped air at system vents.
2 For units with manual air vents, back the set screw out to
expel air from the unit and then re-tighten the set screw.
3 Automotic air vents should require no adjustment for the
coil to vent. However, if the coil does not vent
immediately, unscrew the outer portion of the fitting to
expel air from the port. If debris has become trapped in
the vent, completely remove the outer portion of the
fitting and clean.
Figure 14: Coil Air Vents
CAUTION
Units must be checked for water leaks upon initial water
system startup. Water leaks may be a result of mishandling or
damage during shipping. Failure by the installing contractor to
check for leaks upon start-up of the water system could result
in property damage
IMPORTANT
It is Daikin's policy not to make recommendations on water
treatment. It is the responsibil
ity of the user to check that the
water supply to the units is free of contaminants or corrosive
agents, chemicals or minerals. The general contractor or
owner should contact a local water treatment company
regarding water treatment. A fouled water system will lead to
premature component failure.
Primary coil
air vent
Reheat coil air vent on
factory-installed package