Harmon HydroFlex 60 Pellet Boiler?

[iceguy4]

We are having some problems with our Hydroflex 60. This is the first season that we have used our Hydroflex 60 and up until about a week ago we were pretty pleased with its performance. Since then the unit has not been able to provide the output needed to bring our home up to heat and maintain the temperature despite the temperature in the 30's and low 40's. The last load of pellets (Energex) were a major step down from the Okanagan pellets we had used previously - creating a lot of ash noticed during cleanings.

The unit starts up and appears to be running normally, but when put under a single zone load the boiler temps hover in the 140-150 degree area (min setting = 160, max =180) eventually falling to 140 when the oil fired boiler comes on to boost temps and shuts down after it has done its job. The pellet circulator continues to work and temps fall back to the 140-150 level and eventually needs another boost from the oil burner. Even though there is a demand for more heat the pellet feed does not respond to the demand by supplying more pellets to the firepot. Instead the feed falters - it does come on, but not enough for a high sustained burn in an attempt to meet the btu demand.

I suspect that the temp sensor may be gunked up or has outright failed. Has anyone else had a problem like this? Our latest supply of pellets are Cubex - because of the existing problem it's difficult to judge their performance.

Thanks, Will

Can we assume you have thoroughly cleaned the unit? It seems your problem started when you introduced a dirty pellet. does the flame look "vigorous"? you say"Instead the feed falters" explain...does it get slower? Did you putz with the feed rate? Feed rate can be adjusted (in spite of what some members say) to compensate for pellet quality. Flame lazy...more then likely an air leak...check with cigarette smoke around doors ect. any codes?

 

[VT_Bubba]

We are having some problems with our Hydroflex 60. This is the first season that we have used our Hydroflex 60 and up until about a week ago we were pretty pleased with its performance. Since then the unit has not been able to provide the output needed to bring our home up to heat and maintain the temperature despite the temperature in the 30's and low 40's. The last load of pellets (Energex) were a major step down from the Okanagan pellets we had used previously - creating a lot of ash noticed during cleanings.

The unit starts up and appears to be running normally, but when put under a single zone load the boiler temps hover in the 140-150 degree area (min setting = 160, max =180) eventually falling to 140 when the oil fired boiler comes on to boost temps and shuts down after it has done its job. The pellet circulator continues to work and temps fall back to the 140-150 level and eventually needs another boost from the oil burner. Even though there is a demand for more heat the pellet feed does not respond to the demand by supplying more pellets to the firepot. Instead the feed falters - it does come on, but not enough for a high sustained burn in an attempt to meet the btu demand.

I suspect that the temp sensor may be gunked up or has outright failed. Has anyone else had a problem like this? Our latest supply of pellets are Cubex - because of the existing problem it's difficult to judge their performance.

Thanks, Will

Hi Will,

I hate to agree with IceGuy4 (Humor Intended...), but a complete cleaning is in order here. I would even pull the probe above the exhaust fan and clean it with soap and water. IceGuy4 makes fun of me when I say that I could tell a difference in pellets with my small little HF60, just by watching how the boiler responds to the loading. Different pellets do burn differently in different stoves\boilers. I can truly tell a good pellet from a crappy pellet and I'm now willing to spend another $20-25/ton for the good stuff.

By the way, watch out for the crust in the burn-pot from those Cubex (clogging the air holes in the burn pot). They do burn hot, but I disliked the crust that forms in the burn pot (scrape frequently my friend).

One more suggestion - Read my post above on Auto vs Manual Mode ! Manual mode rocks when you are having trouble getting enough heat out of the boiler. I always use manual mode now, when it's real cold. I use auto mode in mild weather, which cuts down on the pellet consumption.

In summary, solid advice from IceGuy4 ! Full Cleaning, try different pellets, then try cranking up the feed rate on the crappy pellets. Don't be afraid to mix some good pellets with the crappy pellets, to help use-up those crappy pellets.

I hope you will share what you learn with the forum !

VT_Bubba

 

[iceguy4]

IceGuy4 makes fun of me when I say that I could tell a difference in pellets with my small little HF60

I think it has been determined ...I'm a "numb #@^ (#@^ =you know what).
As I get to know MY boiler better , I do see the "nuances" of different pellets. Lately...Pellington's (described as garage absorbent by some) ... Burn kinda nice but leave a crust on burn pot ... Oh yea I get ash as a byproduct ( those S.O.B.'s put ash in their pellets...LOL) I canNOT tell the difference in flame, heat, consumption, or ANY of the indicators others are able to "feel". Personally I think its because I have one of those "smart" stoves Unfortunately, lately its not "smart" enough to light its self.. Hence manual operation.

Are there differences between heat output/ash between pellet brands? NO doubt. does my boiler compensate? "you bet-cha" For me none of these differences rise to the level of overriding my price considerations, making my pellet choices EASY-smeasy!
To the OP, Please keep us in the "loop"....we like to learn.

 

[VT_Bubba]

I think it has been determined ...I'm a "numb #@^ (#@^ =you know what).
As I get to know MY boiler better , I do see the "nuances" of different pellets. Lately...Pellington's (described as garage absorbent by some) ... Burn kinda nice but leave a crust on burn pot ... Oh yea I get ash as a byproduct ( those S.O.B.'s put ash in their pellets...LOL) I canNOT tell the difference in flame, heat, consumption, or ANY of the indicators others are able to "feel". Personally I think its because I have one of those "smart" stoves Unfortunately, lately its not "smart" enough to light its self.. Hence manual operation.

Are there differences between heat output/ash between pellet brands? NO doubt. does my boiler compensate? "you bet-cha" For me none of these differences rise to the level of overriding my price considerations, making my pellet choices EASY-smeasy!
To the OP, Please keep us in the "loop"....we like to learn.

IceGuy4,

All joking a side, I think the big difference between your PB105 and my HF60 is the size of the boiler and the spare heating capacity you have with the larger PB105 (almost 2X the water capacity in a PB105). I bet if you were trying to heat 2X the house with your PB105, you would see more effect. Especially during an "Auto" ignition cycle when the house is calling for full heat (not as bad in manual mode, because the boiler is already fired and can respond to the cold zones pretty quickly).

I have 3 friends with PB105's, many use good pellets in the dead of winter just to minimize cleaning during high consumption months, and then use the "shoulder pellets" when the consumption is lower. It's all about how convenient and how often the cleanings are required. Burning more pellets means more cleaning. Dirty pellets means more cleaning.

BTW - The crust in the burn pot from many Hardwood Pellets is not a big issue if it is scrapped daily. If the crust is not cleaned regularly, it blocks the air flow in the burn pot and the boiler spirals into a rich flame and soots-up the entire boiler. It is also the root-cause of most "Warped and Bubbled" burn pots and most "Auto Ignition problems" too. When you see the new PB105 Burn Pots you will see the design changes to keep the air-flow open and stop the hot spots caused by the crust blocking the air flow in the burn pot.

For me, I'm exceptionally lazy and the extra cleaning from the crappy pellets is just not worth the $20 x 3tons = $60yr. I guess my laziness overrides my cheapness...

VT_Bubba

 

[Mr._Graybeard]

BTW - The crust in the burn pot from many Hardwood Pellets is not a big issue if it is scrapped daily. If the crust is not cleaned regularly, it blocks the air flow in the burn pot and the boiler spirals into a rich flame and soots-up the entire boiler. It is also the root-cause of most "Warped and Bubbled" burn pots and most "Auto Ignition problems" too. When you see the new PB105 Burn Pots you will see the design changes to keep the air-flow open and stop the hot spots caused by the crust blocking the air flow in the burn pot.

VT_Bubba

I'll rebut that point about the burnpot bubble. I think the bubble comes from repeated "cold" ignition cycles that the boiler goes through in auto mode. A lot of boiler burnpots have begun to warp almost immediately after being put to use -- during the shoulder season, when the on/off cycle happens the most. Most stove users don't burn that way, so that's why the boiler is more susceptible.

I think Harman came up with the dirty burnpot scenario because they didn't know what to make of the situation. But after dropping 9 grand on the boiler and installation, believe me, I was fastidious about keeping it clean. My first burnpot was warping by the end of November. Harman installed a second one this summer, and it started warping again before the cold started setting in. I just noticed a few cracks forming this month.

This season, I'm armed with the service bulletin and the part number for the new burnpot design. I may also start burning like Iceguy, in manual mode, to keep ignition cycles to a minimum.

That's my theory, and I'm stickin' with it.

 

[iceguy4]

For me, I'm exceptionally lazy and the extra cleaning from the crappy pellets is just not worth the $20 x 3tons = $60yr. I guess my laziness overrides my cheapness...

Bubba,
This year I poised to burn 11 tons. Next year with my mom living in the 2nt building I'm heating, I suspect it will be slightly higher(new windows installed last week and other improvements may offset the higher temps she will require). Fingers crossed
Using your numbers (not sure just how much better pellet I can get for the $20 you quote)...$220. is almost 4X the monies you save.. Now I have no doubt a better pellet will be a comfortable switch, and I suspect 22 ton loads will be in my future to achieve your numbers

I can say with absolute certainty, NO one on this board is tighter with a buck then ME!! Moths come out of my wallet when I open it...the presidents on my bills ware sunglasses... People who know me say" he's tighter then bark on a tree....I digress

 

[iceguy4]

I think the bubble comes from repeated "cold" ignition cycles that the boiler goes through in auto mode

Personally I think this assessment is "spot on" .....Time will tell... BTW I'm at 9+ tons burned in my "newest design" burnpot... as of last weeks inspection...pristine!! ALL pellets were burned by running in "manual"

 

[VT_Bubba]

I'll rebut that point about the burnpot bubble. I think the bubble comes from repeated "cold" ignition cycles that the boiler goes through in auto mode. A lot of boiler burnpots have begun to warp almost immediately after being put to use -- during the shoulder season, when the on/off cycle happens the most. Most stove users don't burn that way, so that's why the boiler is more susceptible.

I think Harman came up with the dirty burnpot scenario because they didn't know what to make of the situation. But after dropping 9 grand on the boiler and installation, believe me, I was fastidious about keeping it clean. My first burnpot was warping by the end of November. Harman installed a second one this summer, and it started warping again before the cold started setting in. I just noticed a few cracks forming this month.

This season, I'm armed with the service bulletin and the part number for the new burnpot design. I may also start burning like Iceguy, in manual mode, to keep ignition cycles to a minimum.

That's my theory, and I'm stickin' with it.

Mr_Graybeard,

I won't argue that Auto-Ignition may be a factor, and will also say 1 of my PB105 friends burn's at low feed rate and never "Auto shut's down", and still has his original 3yr old Burn-Pot with no cracks or bubbles. The other two PB105's have been through 3-4 burn-pots in about 3yrs. One PB105 user made his Auto-Ignition problems 100% go away, by scrapping the burn-pot daily when using Crusty Hdw Pellets. He is convinced that blocked air holes causes ignition problems and creates hot spots on the burn port, where all of the air goes through the few open holes.

The new PB105 Burn pot I was able to see, looked like Stainless Steel, was larger in size with much thicker metal, and had larger holes and slots for air flow. Two of the three PB105's now have the new burn-pot this season

The funny thing is, I primarily use Auto mode on my HF60 with 15-25 starts a day, and see no signs of cracks or bubbles. However, I do scrape everyday, especially if I'm burning a crusty pellet.

VT_Bubba

 

[heaterman]

All the maintenance and issues listed above are why we don't sell Harmon. The extra couple grand for something like a Windhager is well worth it.
Sorry you guys are having these problems but from what I have seen servicing these things for various owners around here they are not a good investment. Too many headaches, too much maintenance. Alternative fuels save you money but neither the end user or us as a service company want to be "married" to the piece of equipment.

Not trying to start a fight over brands here but the Austrian made pellet boilers are light years ahead of anything made here in the USA.
I post this just for people who may be considering going with a pellet boiler, not to bash someone for the product choice they made. Heck.....how would you know even if you went to see a bunch of brands and just listened to the salesman.
The difference is not easily seen unless you have a good understanding about how a pellet boiler works.

 

[iceguy4]

The funny thing is, I primarily use Auto mode on my HF60 with 15-25 starts a day, and see no signs of cracks or bubbles.

Your post seems to bolster the idea that hot and cold cycles may be the key to this problem, I think you not having problems could be linked to the fact you burn so few pellets.

 

[iceguy4]

All the maintenance and issues listed above are why we don't sell Harmon. The extra couple grand for something like a Windhager is well worth it.

I for one applaud you and your "high standards" I love to buy the best product....I can afford


Some of us have to settle for.... "oats that have been through the horse"

 

[Mr._Graybeard]

If only Windhager had a dealer within a couple hours' drive of me, I certainly would have considered the BioWin. But I can't see making such a big investment without an adequate resource for service. My Harman retailer in Wisconsin is Earth Sense, and they've been very supportive. I would buy from them again in a heartbeat. To me it's the quality of the dealer that made my decision as much as the quality of the product.

And aside from the burnpot issue, my PB105 has been a workhorse. I've burned at least 12 tons of pellets since it was installed in 2012, saving nearly $2500 on heating. I'm quite pleased with it.

 

[Mr._Graybeard]

Mr_Graybeard,

I won't argue that Auto-Ignition may be a factor, and will also say 1 of my PB105 friends burn's at low feed rate and never "Auto shut's down", and still has his original 3yr old Burn-Pot with no cracks or bubbles. The other two PB105's have been through 3-4 burn-pots in about 3yrs. One PB105 user made his Auto-Ignition problems 100% go away, by scrapping the burn-pot daily when using Crusty Hdw Pellets. He is convinced that blocked air holes causes ignition problems and creates hot spots on the burn port, where all of the air goes through the few open holes.

The new PB105 Burn pot I was able to see, looked like Stainless Steel, was larger in size with much thicker metal, and had larger holes and slots for air flow. Two of the three PB105's now have the new burn-pot this season

The funny thing is, I primarily use Auto mode on my HF60 with 15-25 starts a day, and see no signs of cracks or bubbles. However, I do scrape everyday, especially if I'm burning a crusty pellet.

VT_Bubba

Hi Bubba,
I should have demanded that I have the original pot replaced with the new design, but my retailer had this one in stock, and it was strictly a warrantied job. I thought I'd let him do his thing without kibbitzing too much.

At first I thought Burnpot No. 2 was doing pretty well, although a little bump formed fairly quickly once the heating season started. It's still smaller than the bubble on the original pot. But a couple weeks ago I noticed some small cracks forming. (I guess I should add these experiences to the "burnpot bubble" thread in the pellet forum.) I believe Harman says a little warpage is acceptable, but it shouldn't crack.

I notice that Harman has added slits in the "new" pot where the bubble usually forms. I would surmise that it's to accommodate expansion of the burnpot surface when the igniter is working. Good move on their part.

I confess I don't scrape the pot every day (more like every other day), but I try to avoid really dirty pellets. I was burning Somersets at the start of this heating season when the bubble formed. And every time I clean out the pot I take the plate off the ash trap, clean it out and shine an LED flashlight into the trap so the light can reveal any blocked holes. I can't say I've ever seen one, really. The airflow keeps them pretty clean. Anything that looks suspicious, I clean out with a pick.

 

[Doeboy611]

Hi Will,

I hate to agree with IceGuy4 (Humor Intended...), but a complete cleaning is in order here. I would even pull the probe above the exhaust fan and clean it with soap and water. IceGuy4 makes fun of me when I say that I could tell a difference in pellets with my small little HF60, just by watching how the boiler responds to the loading. Different pellets do burn differently in different stoves\boilers. I can truly tell a good pellet from a crappy pellet and I'm now willing to spend another $20-25/ton for the good stuff.

By the way, watch out for the crust in the burn-pot from those Cubex (clogging the air holes in the burn pot). They do burn hot, but I disliked the crust that forms in the burn pot (scrape frequently my friend).

One more suggestion - Read my post above on Auto vs Manual Mode ! Manual mode rocks when you are having trouble getting enough heat out of the boiler. I always use manual mode now, when it's real cold. I use auto mode in mild weather, which cuts down on the pellet consumption.

In summary, solid advice from IceGuy4 ! Full Cleaning, try different pellets, then try cranking up the feed rate on the crappy pellets. Don't be afraid to mix some good pellets with the crappy pellets, to help use-up those crappy pellets.

I hope you will share what you learn with the forum !

VT_Bubba

Thanks for the insight from all. It turns out that it was an air leak in the pellet bin that was the culprit. The unit was detecting a lack of negative pressure and was turning down or off the pellet feed auger - it's hard to burn pellets (and get heat) if they aren't being delivered! I ended up applying silicon to the sheet metal joints on the back of the unit, gave it overnight to dry out and it fired right up the next morning. Before discovering the source of the problem, everything on the unit had been cleaned thoroughly - temp probe, exhaust pipe, fines trap, burn pot and heat exchanger - I am getting pretty familiar with the unit...

The Cubex pellets seem to be pretty good compared to the Energex, but I appreciate the heads up on the scraping as there is a noticeable difference in the softwood - hardwood pellets and build up of more "clinkers" in the burnpot is one of them. I did read the post on the manual operation - tried it but with the air leak, it didn't help much. Still lots of winter to go - thanks again for the assistance.

Will

 

[Doeboy611]

Hi Will,

I hate to agree with IceGuy4 (Humor Intended...), but a complete cleaning is in order here. I would even pull the probe above the exhaust fan and clean it with soap and water. IceGuy4 makes fun of me when I say that I could tell a difference in pellets with my small little HF60, just by watching how the boiler responds to the loading. Different pellets do burn differently in different stoves\boilers. I can truly tell a good pellet from a crappy pellet and I'm now willing to spend another $20-25/ton for the good stuff.

By the way, watch out for the crust in the burn-pot from those Cubex (clogging the air holes in the burn pot). They do burn hot, but I disliked the crust that forms in the burn pot (scrape frequently my friend).

One more suggestion - Read my post above on Auto vs Manual Mode ! Manual mode rocks when you are having trouble getting enough heat out of the boiler. I always use manual mode now, when it's real cold. I use auto mode in mild weather, which cuts down on the pellet consumption.

In summary, solid advice from IceGuy4 ! Full Cleaning, try different pellets, then try cranking up the feed rate on the crappy pellets. Don't be afraid to mix some good pellets with the crappy pellets, to help use-up those crappy pellets.

I hope you will share what you learn with the forum !

VT_Bubba

 

[SmokeEater]

I'll rebut that point about the burnpot bubble. I think the bubble comes from repeated "cold" ignition cycles that the boiler goes through in auto mode. A lot of boiler burnpots have begun to warp almost immediately after being put to use -- during the shoulder season, when the on/off cycle happens the most. Most stove users don't burn that way, so that's why the boiler is more susceptible.

I think Harman came up with the dirty burnpot scenario because they didn't know what to make of the situation. But after dropping 9 grand on the boiler and installation, believe me, I was fastidious about keeping it clean. My first burnpot was warping by the end of November. Harman installed a second one this summer, and it started warping again before the cold started setting in. I just noticed a few cracks forming this month.

This season, I'm armed with the service bulletin and the part number for the new burnpot design. I may also start burning like Iceguy, in manual mode, to keep ignition cycles to a minimum.

That's my theory, and I'm stickin' with it.

I have an older PB105 and have put about 25 tons of pellets through it all in auto mode. I have never run or started the boiler in manual and have no sign of burnpot bubble.

 

[Mr._Graybeard]

It's just my theory, Jimmy -- if you did a poll of all PB105 owners, it may be that only a small minority ever had bubble damage in the burnpot. I don't think Harman has acknowledged a widespread problem, although the repeated burnpot redesigns suggest something is going on.

I didn't mean to hijack this thread. The idea that the bubble was the result of spotty maintenance just got a rise out of me.

 

[SmokeEater]

It's just my theory, Jimmy -- if you did a poll of all PB105 owners, it may be that only a small minority ever had bubble damage in the burnpot. I don't think Harman has acknowledged a widespread problem, although the repeated burnpot redesigns suggest something is going on.

I didn't mean to hijack this thread. The idea that the bubble was the result of spotty maintenance just got a rise out of me.

I like it and though more of a hypothesis, I still like it. It is strange that some, only some of the PB105's have a burnpot issue and yet many others do not. I don't think the pellets used are involved at all, but some factor(s) in the operation of the boiler that lead to the problem. I also can't see how the ignitor can cause this issue either. More likely an concentrated burn at high temp in one part of the burnpot causing very unequal heating and therefore expansion stresses that have cause the metal to fatigue and fail (bubble and crack).