Enter the parameter for DHW menu. Is the DHW limit setpoint 170f?
Go to Error Code First
Use the up or down arrow keys to change setpoint to 170f. When complete press the checkmark to save.
Install a flow restrictor to meet the continuous fraw from the tank.
What is the flow rate of the faucet where the HO is running out of hot water? Get the flow rate from the manufacturer of the faucet. Another way to test is get a 5 gallon bucket.Turn on the hot water faucet and run water into the burcket for 1 minute. How much water is in the bucket? That is the flow rate per minute. Is the one minute flow higher that the rating on the IWH rating sheet?
Note: If your IWH is not manufactured by Velocity Boiler Works you will have to get the information from the tank manufacturer.
Press the right arrow on the right side of the screen and find Differential above. If it is not set to 10f use the up arrow to accomplish this. Some of the earlier controls do not go to 10f, set as high as it goes. Press checkmark to save.
Using the right arrow scroll one screen to thre right to Differential below. Set this to 5f if not already set to 5f. Press checkmark to save.
Install a flow restrictor to meet the spec on the IWH.
Is the piping properly sized between the boiler and the IWH? A good rule of thumb is one size larger than the tappings on the IWH. The tapping should have 1″ piping to and from the IWH due to a 6 gpm flow requirement.
Piping should be upgraded to proper pipe size and flow rate.
Scroll to the right a few more screen using the right arrow key. Find DHW Priority. If it is not enabled, press to enable DHW priority. Press the X in the upper right hane corner a few times until you get back the “Home” screen.
Is the IWH piped per Velocity Boiler Works I&O manual? The piping should be on the system piping as a heat zone. Another option is to pipe the IWH off the boiler supply pipe with a set of closely spaced tees to create a primary/Secondary connection. Is the IWH piped properly?
IWH should be re-piped to spec
Press the “Status” button. Turn up the aquastat or run enough hot water to make the IWH demand. The second line down should show 180f and” Priority” about 3/4 way down should show Domestic Hot Water. Are these displayed as described?
The Setpoint should display 170f but may show something less or more than than 170f. Does the priority show Central Heat?
Is the heat system zoned with circulators or Zone Valves?
Does the IWH have a zone valve or a separate circulator?
Check the wiring, is the IWH aquastat and circulator wired to the multi-zone relay or the boiler?
Check the wiring. Is the IWH aquastat and the DHW circulator wired to the boiler DHW demand terminals on the low voltage board and the DHW circulator wired to the line voltage board?
Is there a wire from the boiler system pump terminals to Zc on the mul;ti-zone relay and the jumper removed from ZR to ZC?
Are the zone valves wired to a Zone Valve Zone Panel or are the zone valve end switches daisey chained together and wired back to the boiler T-T terminals?
Determine where they are wired to and move the wires to the boiler terminals.
Add wire from System Circ to ZC after removing the jumper from ZR to ZC on the multi-zone relay.
Wire as suggested in the drawing. This will override ODR and the zone panel will give priority to the DHW zone valve. Sample drawing is a Taco ZVC-403-4. DHW zone valve end switch must be wired to the Priority zone.
Wire the zone valve end switch for the DHW zone valve to the DHW terminals on the low voltage board.
In the” Pump Setup” menu verify the “System Pump” is set to “Central Heat/Opional Priority”. Did problem Resolve?
The circulator must be wired to the System Circulator” terminals on the line voltage circuit board.
View the “Pump Setup” menu and set pumps as follows. System Circulator – Any Demand, Boiler Circulator – Any Demand and DHW circulator – Never Did this resolve the problem?
Add a mixing valve to the IWH. Set the mixing valve to the temperature the home owner request, the lower the better. Set the IWH aqustat to 160+. The greater the temperature difference the more hot water will be supplied. This will add about 25% more hot water.
Please contact Technical Support to resolve this issue.
Alliance IWH Spec Sheet
GPM Calculation
Enter continuous drawn Gal/hr from chart
Flow GPM = Gal/Hr /60
K2-WT Boiler
