Use and Care Manual

lp-83 Rev. 12.5.16
21
Table 9 - Troubleshooting - *See scald warning below.
If draining of the water heater is necessary, open the T&P valve
or a hot water tap to prevent vacuum buildup in the tank and
piping.
The risk of scald injury increases as you increase water
temperature. Use a water tempering or mixing valve and
extreme caution when using hot water to avoid scald
injury. Consult codes for conformance. Failure to follow the
instructions in this warning statement could result in serious
personal injury or death from scalds.
Problem Reason Remedy
No Hot Water
Zone Valve Not Opening Open manually or replace
Circulator Not Operating Check or replace
Tank Control Set Too Low Raise tank temperature*
Boiler Control Set Too Low Raise boiler temperature
Wiring Incorrect Check wiring
Tank Control Failure Replace control
Zone Valve Failure Replace Valve
Circulator Failure Replace Circulator
Air Trap in Loop Purge Air
Not Enough Hot
Water
Zone valve restriction 1” full bore replace zone valve
Circulator arrow reversed Reverse circulator
Tank temperature too low Raise tank temperature*
Boiler temperature too low Raise boiler temperature
Boiler sized too small
Check sizing chart
Tank sized too small
Demand ow rate too high Install mixing valve. Raise tank temperature
Air trap in loop
Purge air
Install ow regulator
Heat and tank come on together
Check wiring or set indirect as priority over heating
Draw tank down and lower thermostat. Recheck.
T&P Valve
Discharges
Tank Temperature Too High Lower tank temperature
Water Expands When Heated Install expansion tank
Water Pressure Too High Install pressure reducing valve
Hot Tubs, Spas,
Multiple Showers,
High Demand
Pressure Too Low Check line pressure for restriction
Tank recovery slow Slow startup boiler. See chart
Not enough hot water
Boiler sized too small. See chart
Check ow rate. Compare to chart
Demand too great. Check ow rates and compare to chart. Install
mixing valve and/or ow restricting valve and raise tank and boiler
temperature.*