need to descale my tankless heater can you use a sump pump

[loki993]

I have to descale my tankless water heater. I've lost a bit of flow on the hot side apparent and its affecting the water pressure ion the shower.

I have what I need but I didn't want to go spend the only on a pump if I didn't have to. I went to my dads house and he has a half horse sump pump he said I could use. Now I'm not sure but I'm afraid that it could be too much flow/pressure to do the descale.

Can you cause damage to the unit by using too powerful a pump or should I be ok using the sum pump?

[LLigetfa]

Most sump pumps are between 30 and 90 GPM while descalers generally are a tenth of that. Also descaling pumps are resistant to the acid used. Not sure what the acid might do to a sump pump.

[loki993]

Most sump pumps are between 30 and 90 GPM while descalers generally are a tenth of that. Also descaling pumps are resistant to the acid used. Not sure what the acid might do to a sump pump.

Im just using vinegar, nothing serious, the pump should hold up. Im just worried that it may be too much pressure.

[Killer95Stang]

A 1/2 hp unit seems like a huge overkill to descale a tankless. I'll be using a 1/6hp pump I picked up at HF... I'll check in to post the results once I'm done....

[Killer95Stang]

So.. Yesterday I completed my 6 month descaling of my Rheem Condensing Tankless water heater. I used the 1/6hp pump below that I purchased at HF with my 20% coupon. I then sourced two 6ft washing machine hoses, since they already have the needed FPT hose ends installed. I used a clean 5 gallon bucket filled with 3.5 gallons of white distilled vinegar. I first bypassed my tankless from the house water system using my installed service valves, then drained the waterheater. I connected the hoses to the WH and circulated the mild acid solution for 45-60 minutes. After, I flushed the WH twice with clean water using the same pump and bucket, then cleaned the small filter of loose debris.

All said and done, the process was pretty uneventful. I ended up spending about $70.00 for all the supplies needed, which is way cheaper than buying one the $169 pre-made kits.

[loki993]

A 1/2 hp unit seems like a huge overkill to descale a tankless. I'll be using a 1/6hp pump I picked up at HF... I'll check in to post the results once I'm done....

So.. Yesterday I completed my 6 month descaling of my Rheem Condensing Tankless water heater. I used the 1/6hp pump below that I purchased at HF with my 20% coupon. I then sourced two 6ft washing machine hoses, since they already have the needed FPT hose ends installed. I used a clean 5 gallon bucket filled with 3.5 gallons of white distilled vinegar. I first bypassed my tankless from the house water system using my installed service valves, then drained the waterheater. I connected the hoses to the WH and circulated the mild acid solution for 45-60 minutes. After, I flushed the WH twice with clean water using the same pump and bucket, then cleaned the small filter of loose debris.

All said and done, the process was pretty uneventful. I ended up spending about $70.00 for all the supplies needed, which is way cheaper than buying one the $169 pre-made kits.

Yeah I think its overkill too, but the pump didnt cost me anything. I was trying to avoid the biggest cost of the job which is the pump. However Im not going to risk damaging the unit to save some money. Maybe I can run across a pond pump on clearance somewhere.

[saphman]

I agree with you. I have the 1/6 hp pump I bought at lowes. It has just the right amount of pressure and flow.

Another option to descale is using "SULFAMIC" acid powder. This is available through LOW ENERGY SYSTEMS and comes in a 5lb bag. There is a copper protector solution that you add with the powder to a gallon or so of water that is red. When the descaler has circulated and done it's job the water turns clear. It is better than vinegar IMHO.