Troubleshooting Guide
401 House Control
Sensor Testing
- Start by going through the View menu and ask the question am I getting accurate numbers back
- If you're in the middle of a New England blizzard and the outdoor sensor says it's 90°F outside, is this reasonable?
- If you see bad numbers it's time to grab an ohm meter and start measuring. Refer to the sensor manual or 'Sensor Troubleshooting Guide' and follow testing instructions
Boiler Not Running
- Is there a call or is 401 in WWSD?
- In the View menu, what is the Boiler Target vs Boiler Supply? Why fire the boiler if its at target?
- What is the boiler differential? The 401 fires the boiler until it reaches the boiler target, plus half of the differential. Then it waits until it reaches half the differential below the target before firing the boiler again. Is the boiler in the cool down cycle?
- If the boiler symbol is on the screen, is the boiler type configured properly?
- Check the boiler outputs with a multimeter to see if the 401 is sending correct signals to the boiler
- Set boil type to signal you are sending the boiler. Some boilers will self modulate when they receive a heat call
⚠ WARNING
As with any electrical product, care should be taken to guard against potential risks, including electric shock or personal injury.
No Domestic Hot Water
- Is DHW mode turned off? Note the DHW does not follow WWSD
- Is the 401 showing a DHW call?
- If using an aquastat are the contacts for DHW Call closing?
- If a sensor is wired, is the DHW sensor returning an accurate number?
- Is DHW pump wired up and is there voltage at the pump output?
Zone Pumps Not Running
- Is there a call for that zone?
- Is there 120VAC at the pump output
- Is there a DHW call and the DHW mode has given it priority over zones?
Notes
- To see all the temperatures and settings you will have to be in the Installer access level. This is set in the Toolbox menu
- Select Boil Type setting based on the wiring to the boiler. Even though the boiler may be a modulating boiler, if you are only enabling the boiler with the dry 'Stage 1' contacts, then set the Boil Type to 1STG. Only set Boil Type to a modulating signal if wiring the 'Mod dc/mA' terminals to the boiler
- The 401 requires tekmarNet thermostats to recognize a space heating call. If remote access is desired please add either a 482 or 486 Gateway. The 482 is used to let a system like Crestron, Control4 etc. access the system while the 486 will let the system be accessed by the tekmarNet app/web page
Sensor Resistance vs Temperature
Call customer service if you need assistance with technical details.
| Temperature (°F) | Temperature (°C) | Resistance (Ω) | Temperature (°F) | Temperature (°C) | Resistance (Ω) |
|---|---|---|---|---|---|
| -50 | -46 | 490,813 | 20 | -7 | 46,218 |
| -45 | -43 | 405,710 | 25 | -4 | 39,913 |
| -40 | -40 | 336,606 | 30 | -1 | 34,558 |
| -35 | -37 | 280,279 | 35 | 2 | 29,996 |
| -30 | -34 | 234,196 | 40 | 4 | 26,099 |
| -25 | -32 | 196,358 | 45 | 7 | 22,763 |
| -20 | -29 | 165,180 | 50 | 10 | 19,900 |
| -15 | -26 | 139,403 | 55 | 13 | 17,436 |
| -10 | -23 | 118,018 | 60 | 16 | 15,311 |
| -5 | -21 | 100,221 | 65 | 18 | 13,474 |
| 0 | -18 | 85,362 | 70 | 21 | 11,883 |
| 5 | -15 | 72,918 | 75 | 24 | 10,501 |
| 10 | -12 | 62,465 | 80 | 27 | 9,299 |
| 15 | -9 | 53,658 | 85 | 29 | 8,250 |
| 90 | 32 | 7,334 | 160 | 71 | 1,689 |
| 95 | 35 | 6,532 | 165 | 74 | 1,538 |
| 100 | 38 | 5,828 | 170 | 77 | 1,403 |
| 105 | 41 | 5,210 | 175 | 79 | 1,281 |
| 110 | 43 | 4,665 | 180 | 82 | 1,172 |
| 115 | 46 | 4,184 | 185 | 85 | 1,073 |
| 120 | 49 | 3,760 | 190 | 88 | 983 |
| 125 | 52 | 3,383 | 195 | 91 | 903 |
| 130 | 54 | 3,050 | 200 | 93 | 829 |
| 135 | 57 | 2,754 | 205 | 96 | 763 |
| 140 | 60 | 2,490 | 210 | 99 | 703 |
| 145 | 63 | 2,255 | 215 | 102 | 648 |
| 150 | 66 | 2,045 | 220 | 104 | 598 |
| 155 | 68 | 1,857 | 225 | 107 | 553 |
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