hi\lo settings for oil fired boiler

ChasMan

I run my coil at 140 / 160 and the water is hot enough with a low flow shower head. You can not have 2 showers or even run a bath. For a bath I need to run it at 190. I dont know about the fuel savings. When I lowed to 140 / 160 from 160 / 180 it didnt seem to make any difference one way or the other. It did make the system quieter and have longer runs rather than a pile of short bursts all the time. The solution is to get rid of the coil and get an indirect tank. Thats a 3,000 $$ proposition around here.

Anthony Ferrer

hi\lo settings for oil fired boiler

We had the burner on our Burnham America V-15 boiler replaced with a Riello 40. The system is running much smoother now and the heating contractor thinks we should cut our oil bills by about 50%. When he finished tuning the system he set the lo at 140 and the hi at 160. Our problems with hot water were not solved, however. It was suggested the we might need to have the coil acid washed, but some plumbers I spoke to yesterday said that it would only help if we had a reduction in hot water volume, which really isn't the case. One of them asked what our hilo settings are and, when I told him, said that was the problem. He suggested that I change the settings to 170190. I tried that and this morning got the first hot shower I've had in months. So on the one hand I got a hot shower; on the other, I'm wondering if raising the boiler temperature will adversely affect the oil savings we're hoping to get. I'm going to monitor how often the burner kicks on with the higher settings but I'm looking for some experienced guidance. Right now we're just trying to get hot showers until we're ready to put in the indirect hot water heater.

Thanks,

Anthony

Paul Fredricks_2

Sure...

> We had the burner on our Burnham America V-15

> boiler replaced with a Riello 40. The system is

> running much smoother now and the heating

> contractor thinks we should cut our oil bills by

> about 50%. When he finished tuning the system he

> set the lo at 140 and the hi at 160. Our problems

> with hot water were not solved, however. It was

> suggested the we might need to have the coil acid

> washed, but some plumbers I spoke to yesterday

> said that it would only help if we had a

> reduction in hot water volume, which really isn't

> the case. One of them asked what our hilo

> settings are and, when I told him, said that was

> the problem. He suggested that I change the

> settings to 170190. I tried that and this

> morning got the first hot shower I've had in

> months. So on the one hand I got a hot shower; on

> the other, I'm wondering if raising the boiler

> temperature will adversely affect the oil savings

> we're hoping to get. I'm going to monitor how

> often the burner kicks on with the higher

> settings but I'm looking for some experienced

> guidance. Right now we're just trying to get hot

> showers until we're ready to put in the indirect

> hot water heater.

>

> Thanks,

>

> Anthony

Paul Fredricks_2

Sure...

The higher you set the temps, the more fuel you'll use. Probably not drastic amounts more, but some more. My thought would be this; Now that you have the hot water your looking for, start lowering the temps by 10 degrees at a time. See how it works. If you still have lots of hot water, lower it another 10. The lower the better, but you have to have hot water.

Also note that the 2 settings need to be at least 20 degrees apart. The lower setting is the temp the boiler stays at when the heat isn't calling. The upper limit is the temp the boiler tries to get to when there is a call for heat. If the hot water is fine when the heat is calling, it may be cool when the thermostats are satified and the boiler has cooled down a bit.

Nick L. in Vt

domestic coil

whats your differential set at? I like 10 deg for a system with a coil. also, what type of mixing valve do you have?

Anthony Ferrer

The tempering valve is a Watts. Right now it's set full open and the water temp at the first faucet (kitchen sink) is 125. The differential is set at 15. I've lowered the settings to 160180 and we'll see what we get.
Thanks,

Anthony

Nick L. in Vt

domestic h/w

if you feel comfortable with it, isolate the mixing valve and pull the top portion from the body. then exercise the plunger at the bottom of the body with a litte cold water pressure. if that plunger is stuck open with grit/sediment, your valve will feed too much cold to your mix. seen it a ton of times.

Anthony Ferrer

the mixing valve is only about 4 months old, so I doubt it's gotten clogged so soon.

Anthony

Anthony Ferrer

Nothing to add. Accidentally posted twice.

Anthony

Unknown

What type of

aquastat do you have ?

Anthony Ferrer

I had to go check - no one has asked that before. The aquastat is a Honeywell Triple Aquastat Relay, Type L8124A,C

Anthony

Ron Schroeder

I usually set the differential to max as long as the differance between the Lo Limit and Hi Limit is 20 degrees or more. The wider differential will give you some fuel savings from longer runs and less frequient cycling, especially in the summer. Lower the differential only if it delays the circ from coming on too long on a call for heat.

Ron

soot_seeker_2

Burner?

Unless the old burner was one of those cast iron things from the 1940's, replacing it woun't save you too much money. Look for perhaps 10%, if that. Now if you replaced the entire boiler, you may see some real savings.

ANd turning up your aquastat will burn a bit more fuel, but there is a trade off. If you like hot showers, with lots of water, that setting must be higher.

Long Beach Ed

BobM.

hi/lo settings

Anthony, We've had excellent sucsess with electric water heaters as storage tanks using a bronze circulating pump and your tankless. Less expence then indirect installation and you can turn down your lo limit as low as possible. It has saved a lot of oil for people in our area mostly in the summer then fall and spring. Bob M.

Anthony Ferrer

The boiler was one of those 40 year old cast iron ones

Sorry, I wasn't completely clear. We replaced the burner and the aquastat because the system was apparently optimized to waste as much oil as possible. Whenever the boiler temperature got above the lo set point the circulator would shut off. Then the temp would go up to the high set point without the circulator coming on. When it hit the high point the burner would shut down and the boiler temp would drop. When it got to the lo set point the circulator would come back on. When the burner was on it was stuttering and surging, so the boiler never achieved a steady state. Correcting these problems, along with the updated burner, is where the 50% oil savings is anticipated. So far the burner is running noticeably less frequently than before.

Anthony