Suntec A2VA-7116-B: Cracked cover, anyone ever see something like that?

WPL

Hello all,

I'm wondering if anyone has seen the cover or other cast parts on a Suntec pump crack randomly? Here's the full story:

The original fuel pump on my burner developed a leak from the shaft seal just under a year ago. Burner is a Wayne MSR, and that pump was a Suntec A2VA-7116. That pump was original to the burner, both were 8 years old.

That leaking pump was replaced by a service company with the revised Suntec A2VA-7116-B. I had a couple instances of the new pump locking up a bit, and they came back and realigned it and replaced the coupler. The motor would eventually get the pump going--it wasn't locked up solid, but there was some resistance to rotating at times. They did use a bit of Teflon tape on the inlet fitting, against my wishes, so I'm almost suspecting a bit of Teflon got into the pump. It ran more-or-less fine for the rest of the season. Filter at the tank was new at the beginning of last season, and I replaced it again at the end. No sediment or other contamination noted either time, on the filter or in the bowl.

When I went to commission the furnace this year, I found a leak at the pump -- right through an inch-long, vertical crack adjacent to the label on the pump cover.

The cover has never been off the pump (too new to worry about the strainer) and nothing has ever bumped into the burner or its fittings. It is located in a small basement pit that is not used for storage, nor for anything else but housing the furnace. The service company didn't do the trick of transferring the old cover to the new pump; they replaced the entire unit.

So... any guesses? (I'm not after troubleshooting advice for the overall system; I'm going to get someone out to service it--just wondering if anyone has an idea about what happened to the pump itself?)

STEVEusaPA

I don't understand 'locking up a bit'. Coupling problem? Blower wheel misaligned/damaged/not properly gapped?

Someone could've over tightened any of the fittings, especially if using teflon tape, which most pump manufacturers' specifically prohibit/deny warranty.
Or manufacturer defect.

BTW, are you the same guy who posted this on Alan's FB page

WPL

Hello Steve,

No, I've never posted on any other page about this -- in fact, I ditched Facebook in 2016.

Anyhow, with regard to the locking up: on a couple of occasions, there would be a call for heat, the furnace would start up, and then it would go off on lockout. I observed this happening once, and the pump/motor/blower started very slowly, with noticeable "hum" from the motor, and the pump didn't reach a sufficient speed to achieve enough pressure at the nozzle to atomize the fuel for correct ignition. Tried resetting once, and it came up to speed and ran fine. The motor itself is a PSC type and the run capacitor tests okay. Blower wheel seems okay, no noticeable runout, not loose on the shaft, and has correct spacing from motor end. The coupler was replaced when that now-cracked pump was installed, as a preventative measure, but the old one was okay. Pump alignment seems fine.

I suspect that the installer probably cracked the cover slightly when he was screwing the pump onto the inlet pipe (which he did because he couldn't get the flare fitting off the hard pipe section, so he held the pipe and rotated the pump). May have cracked the cover with pliers. The only mystery to me is why the crack wasn't noticeable through the rest of that heating season...? It's not a small crack at all (now).

I spoke with the tech guy at Suntec USA, and the only theories he had were maybe a manufacturing defect, or a bypass plug installed when it shouldn't have been (mine is a single-line system with tank slightly above burner). However, it's definitely not a bypass plug issue; there's no bypass plug installed behind the outlet port plug.

The pump has been replaced with a used Danfoss one (that was all the service tech had with him), so I'm hoping for no more problems. (Incidentally, the tech didn't have the proper bleeder plug for the return port because this pump was off a two-line system and it was absent, so he had to use a standard 1/4" plug... if anyone has a part number for the correct bleeder plug, that would be useful so I can try to source one).

EdTheHeaterMan

Is that new pump you have less than 1 year old? Call the professional installer of that pump and ask if they have any kind of warranty on the service work they do? if they say they do guarantee their work, then ask them to look at the less than 1 year old leaking pump.

This leak sounds like installer error.

I don't recall having an issue like yours with the Suntec A2VA fuel pumps, and I have replaced quite a few in my years of burner work. The slow start sounds like the replacement coupling maybe 1/16" too long causing a binding, resulting in slow start up.

HVACNUT

If your tank is above the burner and single pipe, why a 2 stage pump?

WPL

Installer said no labor warranty, and the office person said she wasn't sure about the parts warranty. I agree that it's probably installer error. I'm not exactly happy about the situation, but I'm not sure how much recourse I have. I may see if Suntec will examine the pump and warranty it if they determine it was a manufacturing defect; that way, I'd at least have a spare. However, I'm guessing they'd determine installer error.

It's difficult to find anyone willing to service oil equipment around here (Southeast) and if you do, it's rare that the person is really an expert at it. I did make sure that the used, replacement pump went on with NO Teflon tape, just non-Teflon pipe dope (yeah, I did watch the tech. I know some guys don't like that, but he actually asked for my help with a couple of things.)

EdTheHeaterMan

HVACNUT said:

If your tank is above the burner and single pipe, why a 2 stage pump?

A2VA pump is a single stage. the B is at the end

WPL

HVACNUT said:

If your tank is above the burner and single pipe, why a 2 stage pump?

Good question... that Suntec p/n is just what the burner shipped with. My understanding is that the AV2A-7116 is just a single-stage pump.

(Edit: Ed beat me to it... supposedly, the "B" variant has Viton seals to better withstand "B"iofuels.)

EdTheHeaterMan

Where in South East?

WPL

I'm in Upstate SC. There are some guys in the Spartanburg area who have great reputations and who do service oil equipment, but they say I'm outside their service area.

EdTheHeaterMan

I'm retired in Charleston SC. Not much oil heat in these parts y'all