HTP EL-110, Installation & Start-Up Manual

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LP- 293 REV. 9.2.14
Pressure relief valve:
Factory supplied on Boiler. The pressure relief valve is sized to ASME specifications. Storage tank may require additional relief valves
depending on local codes.
MINIMUM PIPE SIZES
EL 80/110/150/220
1” NPT or Copper
EL 299/301
1 ¼” NPT or Copper
EL 399
1 ½” NPT or Copper
Table 8
K. FILL AND PURGE HEATING SYSTEM
1. Attach the hose to balance and purge hose connector or drain valve and run hose to nearest drain.
2. Close the other side of the balance and purge valve or shut off valve after the drain.
3. Open the first zone balance and purge or drain valve to let water flow out of the hose. If zone valves are used, open the valves one at
a time manually. NOTE: You should check zone valve manuf
acturer’s instructions prior to opening valves manually, so as not to
damage the zone valve.
4. Manually operate fill valve regulator. When water runs out of the hose, you will see a steady stream without bubbles. Close the
balance and purge valve or drain to stop the water from flowing. Disconnect the hose and connect it to next zone to be purged.
5. Repeat this procedure for additional zones (one at a time).
For installations that incorporate standing iron radiation and systems with manual vents at the high points, follow the previous section
and, starting with the nearest manual air vent, open the vent until water flows out. Then close the vent. Repeat the procedure, working
your way toward the furthest air vent. It may be necessary to install a basket strainer in an older system where larger amounts of
sediment may be present. Annual cleaning of the strainer may be necessary.
Upon completion, make sure that the fill valve and zone valves are in automatic positions. You must also assure the purge and shut off
valves are in open positions.
L. GLYCOL ANTIFREEZE SOLUTIONS
Use only inhibited propylene glycol solutions which are specially formulated for hydronic systems. Ethylene glycol is toxic and can
attack gaskets and seals used in hydronic systems. Glycol mixtures should not exceed 50%.

Glycol in hydronic applications should include inhibitors that prevent the glycol from attacking metallic system components.
Make certain that the system fluid is checked for the correct glycol concentration and inhibitor level.

The glycol solution should be tested at least once a year or as recommended by the glycol manufacturer.

Anti-freeze solutions expand more than water. For example: A 50% by volume solution expands 4.8% in volume for a
temperature increase from 32
o
F to 180
o
F, while water expands 3% over the same temperature rise. Allowances must be made
in system design for expansion.

A 30% mixture of glycol will result in a BTU output loss of 15% with a 5% increase in head against the system circulator.

A 50% mixture of glycol will result in a BTU output loss of 30% with a 50% increase in head against the system circulator.
It is highly recommended that you carefully follow the glycol manufacturer’s recommended concentrations, expansion requirements,
and maintenance recommendations (pH additive breakdown, inhibitor reduction, etc.) You must carefully calculate the additional friction
loss in the system as well as the reduction in heat transfer coefficients.
M. ZONING WITH ZONE VALVES
1. When zoning with zone valves, connect the boiler to the system as shown in Piping Details, Part 4, Section G. The
primary/secondary piping shown ensures the boiler loop will have sufficient flow. It also avoids applying the high head of the boiler
circulator to the zone valves.
2. Connect DHW (domestic hot water) piping to indirect storage water heater as shown in Piping Details.