Boiler: DHW not staying warm.


  #1  
Old 03-15-17, 08:00 AM
E
Member
Thread Starter
Join Date: Mar 2017
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Boiler: DHW not staying warm.

Hi guys, before you tell me to read other posts, I tried to look at most with similar issues but couldn't find anything that has worked. - so here it goes-

I have been seeing a little water on my basement floor now and again and it was kind of near a crack so I figured maybe it was just ground water coming back up ( I bought the house about 3 months ago so I am still learning a few details) and I finally figured out the pressure relief on the boiler was dumping water. I looked and thought maybe it had some junk stuck in the gasket so I flushed it a bit into a bucket and then it made it worse so I hit the shutoff on the boiler (you know that red plated switch that says shutoff on it, I can't remember if the boiler was running at the time I flipped the switch). It stopped and I fired it back up, no issues and it started leaking again and then I realized the valve was set to relieve pressure >30psi and the gauge was at about 31-32psi. So then I looked to my PRV and toned it down until I was at about 20PSI, supposed recommended pressure.( the MAWP on the boiler says 50psi). The leaking stopped, so then later that evening i noticed my hot water was not as hot anymore, which shouldn't be affected since the PRV doesn't effect that, they aren't connected(besides upstream on the feed). The coil is relatively new ~1 year, so I figure it's not clogged, but the question is now, what happened? The only thing I can think of is when I killed the power, something changed the settings? The aqua stat uses knobs, not a digital setting. I am at a loss. Any help would be appreciated.

The boiler is an ultimate PFO-5T, and is about 11 years old.

EDIT: the most important info i forgot to add - this morning my shower would only stay hot for about 3 minutes then turned cold (not sudden, but gradually went from warm (not hot) to cool. sinks also do the same thing. i went down and checked the hot water line effluent of the boiler and it was ice cold like it was the main water feed to the house.
 
  #2  
Old 03-15-17, 08:36 AM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
What is the temperature of the boiler & the settings on the dials of the aquastat?
 
  #3  
Old 03-15-17, 09:09 AM
E
Member
Thread Starter
Join Date: Mar 2017
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
The Temp floats between 170 -190, and the aquastat is set with a high of 190, low of 170 and diff of 10.

I was going to bump it up, however it worked beautifully before even on the single digit degrees days we have up here in new england, so i cant see why anything would be different now. unless the pressure made that much of a difference.
 
  #4  
Old 03-15-17, 11:27 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 64,939
Received 3,951 Upvotes on 3,544 Posts
When the hot water supply ran out was the boiler running ?

The temp floats from 170°-190° but what was it when you ran out of hot water ?
 
  #5  
Old 03-15-17, 12:00 PM
E
Member
Thread Starter
Join Date: Mar 2017
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
I have never seen the temp below 170. This includes when the water is ice cold.

I ran the hot water last night and it was warm, then got cold and while it was cold the boiler didn't start for approximately 2-3 minutes. The boiler did eventually start once it hit about 170.

as of this afternoon, there is no hot water at all. it starts cold, then gets even colder. The baseboard heating is still working fine. I pulled off the side of the boiler to expose the mixing valve. It is a Honeywell AM-1 series. It is my belief that this is stuck on effectively 100% bypass so the cold is blasting right through and none of the water is being forced through the coil (or my coil is blocked which is scary to think of). I did adjust the mixing valve to allow for max hot and it was hot for a short period of time but now back to ice cold. I think I am going to take it out and see if there is any malfunction here.

the valve itself is hot since it obviously is piped together with the boiler, but the hot doesn't appear to be making its way through. The coil piping is warm as well.

does this sound logical? could it be coincidence that the valve all of a sudden decided to fail when i was adjusting the pressure for the baseboard heating side? if i replace the valve, does anyone recommend a brand that wont fail in a year? like apparently my Honeywell did.

thanks
 
  #6  
Old 03-16-17, 05:38 AM
E
Member
Thread Starter
Join Date: Mar 2017
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
I took the thermostatic mixing valve apart last night. didn't appear to have any buildup internally or anything like that, i boiled some water in a tea kettle, placed the element into the hot water to see if it was expanding and it popped right out. i ran it under cool water and it shrunk right down. I put the valve back together and reinstalled it and now it seems to work fine. I bought another one to have in case this one fails again. The Honeywell valve is only about a year old which is disappointing. I went with TACO since it was the original brand that was used. I know this because i found the instructions for the TACO wedged into the insulation on the inside of the boiler enclosure. Half of it was burned and black - and people wonder why i do everything myself.

I hope this helps someone in the future who needs it.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: