TX Series Installation, Operation, and Maintenance Manual
Diversified Heat Transfer, Inc.
439 Main Road, Route 202
Towaco, New Jersey 07082
Page
25
of
33
Phone: 800-221-1522
Website: www.dhtnet.com
3.
Insufficient boiler water
flow to heat exchanger.
4.
Boiler water or domestic
water inlet strainer clogged.
5.
The heat exchanger coil is
scaled.
6.
Water heater being used at
higher than rated design
capacity.
temperature if necessary.
3.
Check to ensure proper boiler water flow to heat
exchanger per design conditions. Also check the feed
water circulator for proper operation.
4.
Blowdown and clean the strainer.
5.
Clean the heat exchanger per instructions. Call DHT or
your authorized representative for instructions on
repair or replacement if necessary. Also ensure the
water quality levels are within the allowable limits.
6.
Check to make sure the operating conditions do not
exceed the design conditions. Use larger size unit if
load exceeds the design capacity.
Temperature and
Pressure relief valve
“pops.”
1.
Improperly sized or
disconnected expansion
tank in closed loop piping
system.
2.
System/incoming water
pressure is too high.
3.
Relief valve is faulty.
4.
Aquastat not properly set or
defective.
1.
Install the properly sized expansion tank in the closed
loop piping system as shown in Installation and Piping
drawings in Section 4.2.
2.
Bring the system water pressure below the relief valve
setting.
3.
Inspect and adjust or replace the relief valve if it has
failed. Contact DHT representative for replacement.
4.
Check and readjust as necessary. Replace the aquastat
if faulty.
A loud banging noise
in the water heater or
water piping (not to
be confused with a
normal clicking noise
made during
operation).
1.
Water return piping has not
been installed properly to
allow the water return
circulation; the water return
line is restricted; or the
water return check valve is
leaking or has failed.
2.
Improperly sized or
disconnected expansion
tank in closed loop piping
system.
3.
Inadequate water hammer
arrestors.
1.
Rearrange the water return piping and inspect the
valve for proper drainage. Also check to make sure
there is no restriction in the water return line. Replace
the check valve if it is leaking or has failed.
2.
Install the properly sized expansion tank in the closed
loop piping system as shown in Installation and Piping
drawings in Section 6.3.
3.
In order to avoid any shock waves, install water
hammer arrestors/shock absorbers in the hot and
cold water systems as needed. Also check for any
trapped air in the domestic water system.
Excessive boiler
cycling
1.
Aquastat not properly set or
defective.
2.
Load is excessive.
3.
Incorrect boiler
temperature limit settings.
1.
Check and readjust the set point settings on aquastat.
Replace the aquastat if faulty.
2.
Water heater is undersized or reduced load. Use
larger size unit.
3.
Increase boiler temperature limit settings.
