Coalpail.com Forum

McGiever wrote: ↑

Wed. Jun. 26, 2019 3:58 pm

Where can I get a coal fired combi-boiler?

Install an AA-260 for DHW only use along side of your AA-130. DHW requires twice the heat of home heating.

The Combi-Coal Boiler...
LOL...

nepacoal wrote: ↑

Wed. Jun. 26, 2019 7:32 am

Wow, i never looked at NG boilers water capacity.

Don't know about the capacity on the one they installed here at my Grandmother's but it's not much. It only takes 1 or 2 minutes to bring it up to temp, you can watch the digital gauge go up, probably about a degree or two each second. The aquatstat by default has no lo setting so the water will drop to ambient room temp if there is no call for heat. Even if you wanted to set it it's blocked from factory from being set above 120.

I stand corrected. A Combi-Boiler is not two boilers in one. It only has a single burner and it incorporates a water to water heat exchanger to provide DHW. Anytime that DHW is flowing heat to the home is cut off.

lsayre wrote: ↑

Mon. Jul. 01, 2019 7:25 am

I stand corrected. A Combi-Boiler is not two boilers in one. It only has a single burner and it incorporates a water to water heat exchanger to provide DHW. Anytime that DHW is flowing heat to the home is cut off.

With that being said, then the boiler sizing would need to match the sizing requirements of which ever is the larger of the two loads...generally that is the DHW side.
Seems this negates the fuel savings sought by using a combi-boiler...

McGiever wrote: ↑

Mon. Jul. 01, 2019 9:45 am

With that being said, then the boiler sizing would need to match the sizing requirements of which ever is the larger of the two loads...generally that is the DHW side.
Seems this negates the fuel savings sought by using a combi-boiler...

That is correct. From what I have read, the combi units are normally oversized for many homes.

The one I'm considering can only put 52,000 gross BTUH output into home heating, but it puts twice that into domestic hot water heating. All from the same burner. Very confusing.

Those combi units are also sensitive to low flow rates. A friend of mine has one, and said if he takes a cool shower he can feel the burner cycling off and on.

I would also expect some kind of annual maintenance to flush out the heat exchanger.

One of the combi's I looked at (I believe the Weil-McLain AquaBalance 2) has a programmable percentage of output that can be assigned to home heating only, so for example if it delivers 150,000 BTUH for DHW, and its home heating percentage is set to 35%, then it can only deliver 52,500 BTUH into the zones of the home. I believe this is the first one I've come across that is being honest in explaining why the other unit I looked at has a single burner and claims 120K BTUH for DHW and 60K BTUH for home heating, with the presumption that rather than the home heating "cut off" being end user selectable as to percent, it is fixed at 50%.

The one with end user percentage selectability is great for dialing in the boilers max output to perfectly match the homes heat emitters and never (in theory) exceed them.

lpg here is Central pa i just received a price for .879 cents per gallon . I use the gas for the temperate fall and spring when the highs may be 48 and the coal for the rest of the season. I use the same piping system but separate boilers of course. Its good to have two fuels for economy and redundancy

As fate has it, my coal supplier could not come up with Lehigh and offered me Blaschak at the Lehigh price. Delivery was made today.

Lehigh usually less expensive than Blaschak?

franpipeman wrote: ↑

Wed. Jul. 17, 2019 8:17 am

Lehigh usually less expensive than Blaschak?

Around here it is.

I have installed a few of those Weil Mclain aquabalance boilers. They are a nice unit. They modulate so that the unit is on most of the heat call as long as it does not reach high temp. The other nice feature is that it comes with the sensor for outdoor reset. I only had a issue with one unit and that is when they first came out. The factor rep met me at the install site. We ended up replacing a control board. Knock on wood no issues since. That unit was a Williamson, but they are the same unit.
-Jason

Update on the natural gas line for our street: This is getting more weird by the day. My wife and I finally got around to asking several neighbors up, down, and across the street if they are happy about natural gas coming, and if they received the 'Consumer Gas Cooperative' letter of application into the Co-Op? Well, as it turns out not one of them knew what we were talking about. So my wife and I drove about 30 miles south of here to 'Consumer Gas Cooperative' to see what was going on, and a company representative told us that everyone (except my wife and I) must have seen the letter as spam or junk mail and tossed it out. The rep. said new letters would go out pronto to everyone on the street. That was several weeks ago, and to date no one has seen a letter. So we went to our township zoning commissioners office and asked if they knew anything, and it was like seeing a deer in a headlight. Across the street to the roads department, and we got the same look. And get this, we can almost hit these township buildings with a stone from our house, and they are natural gas heated by, you guessed it, 'Consumers Gas Cooperative'. Ditto the township police and fire department buildings.