Question about Honeywell Heating & Cooling

Open Question

My Honeywell L4103 Aquastat & High Limit Controller for my oil-fired hot water tank won't set the temperature no matter which direction the setpoint scale is turned. Instead it cuts off via the high limit controller at around 140ºF which is too hot. I would like to set it to 120ºF. Can this be repaired or do I have to replace the entire controller? rjs@goodread.com

Posted by on

5 Suggested Answers

refritech08
  • 149 Answers

SOURCE: I want to adjust the

To enter the adjustment mode, press the UP, DOWN, and I buttons simultaneously for three seconds. Press the I button until the feature requiring adjustment is displayed:
• HL —High Limit.
• LL— Low Limit.
• Ldf —Low Limit differential.
Then press the UP and/or DOWN buttons to move the set point to
the desired value. After 60 seconds without any button inputs, the
control will automatically return to the READ mode.

(copied from honeywell's instructions)

to clarify the differential is cut in minus the cut out.
Hope i can be some help to you.

Posted on Apr 21, 2008

  • 15 Answers

SOURCE: have an oil fired boiler

These boilers usually have multiple controls. The control that would take it out of the circuit at 210 degrees is a safety.

You should definitely have a professional take a look at this unit before you continue using it.

Posted on Sep 18, 2008

  • 234 Answers

SOURCE: what would the correct high and lo and diff

I would say high if you need cooling. If the tempature is cool enough for you then set it to low.If you are hot and need more cooling then high.

Posted on Apr 07, 2009

Therinnaiguy
  • 1420 Answers

SOURCE: what is the recomented settings for high and low

180 with a differential of 15 or 20. So 180 high and 160-165 on low.

Posted on Nov 03, 2009

Testimonial: "Thanks"

  • 949 Answers

SOURCE: HI IAM A ELECTRICIAN WORKING

I would suspect a water circulation problem, most likely air in the system, if the water can't flow it will overheat.

If the problem persists after bleeding check to make sure the pump is running

Posted on May 06, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Wickes 102 combi boiler constantly loosing water pressure


It sounds like your thermostat could be the problem. Have you noticed the boiler cutting off at all, or does it run continuously until it goes out on low water?

You stated, "when boiler is on", so I am wondering how you get the boiler on. If your boiler is controlled by a thermostat, you need to check it for a cold draft possibly from behind the thermostat in the wall where the wires come through. The thermostat should never be on an outside wall. The thermostat could be defective.

An aquastat can also control your boiler. If you have an aquastat, check the setting, typically 175 - 180 degrees. You should also have a "high limit" which should be set at 210 - 220. Some people run that high side limit higher; not a good idea - defeats the purpose. If the aquastat is set too high, the boiler will operate too hot and the problem you have will occur.

"pressure rises and pressure relief valve opens" This could mean that your pressure switch is prematurely venting. Check boiler temperature to see exactly at what temperature the T&P valve purges. If it blows off below the high side setting, either adjust or replace. The T&P valves are usually not adjustable. That blow off temperature is stamped on the head of the valve. So, if it discharges too soon, replace it.

Have you actually seen evidence thgat the T&P valve is opening? You may have a bad bladder in your expansion tank and your system may have air in it. Your boiler should have 12 psi when cold and 20 - 22 psi when operating. Check your boiler pressure guage.

"
this eventually drops below the minimum operating pressure" Technically, there is set point for a NO MINIMUM OPERATING PRESSURE. That is a function of the amount of water in the boiler. If the T&P is blowing off, it will vent water from the boiler and the boiler pressure will go down. There is a minimum operating TEMPERATURE.

Your boiler could be low on water. You will have to manually fill the boiler. Be careful of thermal shock to the boiler. Feel the piping, and fill only when the circulator is running. Make sure the water is not going directly into the boiler. The supply water should go into the circulating supply side which feeds the radiators, radiant floor, or base board circuits.

All this will adversely affect your hot water. The heat exchanger for the potable hot water may have scale build up in it. Using the hot water keeps the boiler running, and a scaled heat exchanger will give you cooler hot water and the boiler keeps running. If this is a problem, you will need to replace the heat exchanger. A better idea is to not use the boiler for your domestic hot water. Why run the boiler in the summer?

Feb 02, 2013 | Water Heaters

1 Answer

Is it possible to lower the top temperature on the thermostate. I can change the lower temp but not the max which I wish to set below the 180 level. Thanks


there is a high and a low limit on these units, the two control knobs are actually the reverse of what you are trying to accomblish,first lower the bottom or low cut off temp first then the high temp ,it must cycle a couple times for it to adjust

Jun 06, 2011 | Honeywell L4103A1019 combination aquastat....

1 Answer

My L4103 aquastat is set too hot, it does not clearly stat temps on set dial which way do i turn it to lesson temp


phl4103-3.jpg on the left side of the dial will be a little metal arrow that will not move when the dial moves, this is the set point. set the temp. you want at this point.

Dec 17, 2010 | Honeywell Heating & Cooling

1 Answer

My john wood hot water tank over flows through the relief valve every 3 - 6 months. The hot water is too hot and I can't seem to adjust the Aquastat L4103 on the hot water heater to a good temperature....


There should be plate on the front of the hot water heater tank.. Pop that off..
There might be some insilation to move and you should see a set screw for adjusting the temp..
If there are no indications for hotter or cooler - then do a 1/8 turn to a 1/4 turn counter clockwise..

Hope this helps !I
rate me good ;o)

Jul 14, 2009 | Honeywell Heat/Cool Thermostat

1 Answer

What would the correct high and lo and diff settings for the Honeywell L8124A Aquastat I have a wood fired boiler with the oil fired boiler side by sides,


I would say high if you need cooling. If the tempature is cool enough for you then set it to low.If you are hot and need more cooling then high.

Apr 05, 2009 | Honeywell Heating & Cooling

1 Answer

I want to adjust the hi and low water temp limits for my oil hot water boiler; I have a Honeywell L7224 aquastat but I cannot find any temperature indicators; how can I do this?


To enter the adjustment mode, press the UP, DOWN, and I buttons simultaneously for three seconds. Press the I button until the feature requiring adjustment is displayed:
• HL —High Limit.
• LL— Low Limit.
• Ldf —Low Limit differential.
Then press the UP and/or DOWN buttons to move the set point to
the desired value. After 60 seconds without any button inputs, the
control will automatically return to the READ mode.

(copied from honeywell's instructions)

to clarify the differential is cut in minus the cut out.
Hope i can be some help to you.

Apr 21, 2008 | Heating & Cooling

Not finding what you are looking for?
Heating & Cooling Logo

Related Topics:

566 people viewed this question

Ask a Question

Usually answered in minutes!

Top Honeywell Heating & Cooling Experts

Bill Long

Level 3 Expert

587 Answers

paulcarew

Level 3 Expert

2404 Answers

Brandon Berry
Brandon Berry

Level 2 Expert

407 Answers

Are you a Honeywell Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...