Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Thermal switch

johnl45
johnl45 Member Posts: 3
in THE MAIN WALL
Weil PHE5 burns up thermal switches any ideas or where to find manual? This thing has been hacked to the max old parts all over the basement, looks like everything has been changed at one time or another. Gas pressure is ok; combustion blower pressure switch doesn't trip. I have measured temp at sensor location in excess of 400° with no obvious flame rollout.

Comments

  • David_5
    David_5 Member Posts: 250
    My guess

    I had a VHE with a bed pressure switch. I replaced it with a general replacement pressure switch and the boiler worked good. 2 days later customer calls back with no heat again. When I got there the thermal fuse thing was open. I found the pressure switch works slower than the factory one. On shut down the draft inducer would shut off and the gas valve would be deenergized by the pressure switch. The delay between the draft motor shut down and the pressure switch opening was about 5 seconds. This let the flame rollout and open the thermal fuse. The factory pressure switch is on order now.

    David
This discussion has been closed.

Categories