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Aquastat question

Greetings from Juneau.

So I'm staying in a house with an oil fired boiler. The thing works great. The trouble is the aquastat buzzes like crazy. I can just touch the relay slightly and it goes away for a minute or two. So before I drop some cash getting a new one, I was curios if someone had in their bag of tricks a little help.  It's a Honeywell L8148A.

BTW- If your on the east coast and wondering where all of winter went? Alaska took it all!


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,375

    The only thing you can do is verify the incoming voltage and hertz are correct, all wire connections are it tight. If all that is good, gotta buy a new one.

    And thanks for taking our winter!!!!!! A mild one once in a while is nice, albeit unprofitable.
  • billtwocase
    billtwocase Member Posts: 2,385
    there is, but

    You should have it replaced
  • Saverio DeLuca
    Saverio DeLuca Member Posts: 5

    Before you buy a new control, check this out. You say when you touch the relay the buzzing stops for 2 minutes then starts again. On the L8148A as well as on other controls today, there is not a lot of room for wiring connections inside the control so alot of times the wiring is crammed in which does not allow the cover to fit securely, leaving the cover loose and vibrating which can cause a buzzing sound. The cover tightens with a screw sometimes at the bottom and/or top which secures the cover in place. The cover may not be properly secured. If you do take the cover off, make sure you shut off the boiler switch. While the cover is off there are also two screws in the back of the control that secure the control onto the aqaustat well. If those are loose, the metal clamp that sits between the well and the aquastat can also vibrate and cause a buzzing sound. Be sure those screws are secure. Slide the cover back on, you'll see the grooves in the cover that have to fit over the top and bottom of the control. Be careful not to pinch any wires as you slide the cover back on. Tighten the cover screws securely, turn the boiler back on, and see if the control is still buzzing. If the control still buzzes and it stops while you hold your hand on the control, it's most likely that it's a metal vibration between the metal cover and the control which is not uncommon and it's likely that there is nothing wrong with the control. Like to know how it works out for you.
  • billtwocase
    billtwocase Member Posts: 2,385

    it's the paint that is gone from the under side of the relay. The older style was easier to repair. It is a magnet/bare metal thingy
  • Plumdog_2
    Plumdog_2 Member Posts: 873
    Sometimes a short...

    In the Thermostat connection can cause the relay or transformer to buzz. I would try disconnecting the wire (open the zone valves manually if you have them) and place a jumper to test. If there's a grounded end switch wire somewhere it can cause buzzing or even burn out the little transformer in the Aquastat. 
This discussion has been closed.