Changing hot water to Heat Pump, what do I use for backup baseboard heat?

802Abell

I reside in Vermont, and currently use a wood pellet stove as my primary heat source. I have a #2 fuel oil furnace being used for hot water and is available for backup baseboard heat. Over the course of 9 years I have only used the baseboard heat once, which was for about 8 days while waiting for a replacement part for the pellet stove. I have a family of 6 in the house, and 2 in an in-law apartment. The in-law apartment has it's own heating sources and only uses the hot water from the main house. I am ready to make a change for multiple reasons (to fix the awful plumbing install, to reduce the footprint in the basement by removing the oil tank and furnace, to reduce the need for a chimney as it is leaking and failing).

I am considering installing a Rheem XE80T10HS45U0 (Electric Heat Pump Water Tank) for the hot water replacement.

What can I do for the backup baseboard hot water? As the baseboard heat is rarely used, could I install an electric on demand heater? I would assume that using the heat pump water tank with a heat exchanger would not work at all?

Thank you,

Ryan

Ironman

An electric on demand would require a very large circuit and possibly a service upgrade, not to mention that it’s not designed, controlled or approved for space heating.

An electric water tank only produces 15.3k btus per hour which no where near enough to heat the house. The same goes for a heat pump water heater.

You’ve got to think in terms of what’s needed if you stop using the pellet stove or if you have to sell the house.

A small mod-con boiler with an indirect water heater would be my recommendation. It would be propane powered.

Rich_49

ve a look at this as opposed to the HPWH . At present HPWHs are suffering many failures for many reasons . With the amount of folks you have in the house it would be a bad idea also . Imagine having to schedule showers , laundry and when to do the dishes . They , well , quite frankly suck . The water heater I am linking to could easily handle your demand . As far as a backup boiler , I would lean toward something propane and as small as you'd require , it making domestic hot water would be optional . https://www.htproducts.com/everlast-elevate-demand-response.html

DCContrarian

Keep the fuel oil boiler for backup heat. And backup hot water if the heat pump fails.

Hot_water_fan

are you using an oil domestic water heater as the central heater? Or is this a boiler connected to a separate tank (AKA an indirect)? Maybe a picture could help.

If an indirect - just keep the boiler as backup. You could also consider an air to water heat pump, which would heat both house and DHW (this option is more involved). A tankless water heater should never be installed unless you have zero room, which doesn’t apply here. If you’re considering electric resistance as backup, just directly installing electric baseboard is extremely reliable and easy. Just abandon the hydronic distribution entirely, although this option would cut off future heat pump central hydronic heating.

Big Ed_4

Back up heat only and to remove equipment … I thinking electric strip heaters

802Abell

Thank you all! I appreciate the feedback regarding the Heat Pump Hot Water heaters, making me shy away from them, thank you.

I really want to remove the old boiler, to save space in the basement (by removing furnace, oil tank and awful plumbing job) and to retire the failing chimney.

I like the electric baseboard option. I thought the Heat Pump Hot Water heater would be a cheaper and easier option than the propane install. The direct vent option of the propane furnace will eliminate the chimney, and relocating to a different wall in the basement will allow a fresh plumbing installation as well.

I’ve attached a picture of the existing

Hot_water_fan

You cannot use a heat pump water heater (like a Rheem, AO Smith, etc. - one that is not connected to the outdoors and is built to heat DHW) to heat a house. Full stop. It operates by taking heat from the house to heat the water. You would, in effect, turn an extremely efficient heater into an extremely inefficient heater, plus it’d be too small either way. A HPWH is a great way to heat domestic hot water though!

Electric baseboard would delete the boiler (not furnace) and all hydronic tubing but you would still have a tank. Either a HPWH or a plain electric resistance tank would solve the chimney problem. A propane boiler would also be more compact. The issue with electric baseboard is that you might be cutting it close with electric service space.

Jamie Hall

There's another problem with electric resistance baseboard, besides very likely having to upgrade your service entrance and electrical panel. Money. Not just in running the thing — electric resistance heat is the most expensive option that you could possibly have — but resale on the house. Unless this is your forever home, a buyer is going to look at all electric resistance heat and suddenly become very reluctant…

Hot_water_fan

Agreed but this is a seldom used backup. Probably does make sense to pay more in operating costs and cheap install costs vs paying much more for an oil boiler that probably is slightly cheaper to operate.

Steamhead

Keep the boiler and hydronic baseboard. That's a good boiler and will serve well with proper care. Use the heat pump unless it gets down past freezing, then fire up the boiler.

That boiler can also be changed to gas firing using a Carlin EZ-Gas burner.

DCContrarian

https://forum.heatinghelp.com/discussion/comment/1807777#Comment_1807777

Relatedly, insurance companies have become increasingly reluctant to insure houses with solid fuel burning appliances. And increasingly insistent that the house have a thermostat-controlled heating system as well so the pipes don't freeze if the owner isn't able to keep the fire going for some reason.

Hot_water_fan

Use the heat pump unless it gets down past freezing, then fire up the boiler.

@Steamhead I think there’s confusion. We’re talking about a domestic hot water heat pump. I don’t think we’ve even broached the subject of a central heating heat pump.

pecmsg

https://forum.heatinghelp.com/discussion/comment/1807782#Comment_1807782

the OP did state he wanted to free up space by getting rid of the boiler and oil tank.

Big mistake in my book!

Hot_water_fan

I think a tank for DHW is almost always the answer.

802Abell

I would like to keep a DWH tank, especially with the number of members in the household. Priority one is to eliminate the need for the chimney, as it is leaking and would rather put the cost of chimney repairs towards a different heating system. Priority two is to reduce the footprint of the current heating system in the house (fuel oil tank, existing plumbing mess).

Vermont’s current rebate on heat pump water heaters put me down the path of thinking about installing one. With the need for backup heat the heat pump water heater doesn’t seem like an option. The current boiler that I have could be converted to direct vent propane???

pecmsg

https://forum.heatinghelp.com/discussion/comment/1807799#Comment_1807799

who said that boiler could be converted to direct vent?

are you planing on taking down that chimney?

Hot_water_fan

I think there’s much confusion here: the HPWH doesn’t need any sort of backup, but it is limited to DHW.

802Abell

https://forum.heatinghelp.com/discussion/comment/1807801#Comment_1807801

There was mention of converting to gas firing using a Carlin EZ-Gas burner. With that, would that allow for direct vent?

Yes, will be removing the chimney.

pecmsg

https://forum.heatinghelp.com/discussion/comment/1807803#Comment_1807803

depending on the age of that boiler you might be better off going with a 96% LP condensing boiler

HVACNUT

https://forum.heatinghelp.com/discussion/comment/1807775#Comment_1807775

You've got a Weil Mclain GO cast iron, wet base boiler. Yes, it needs to be properly piped, but the boiler itself should last. And any reputable service tech would have any replacement part in the truck.

A new oil tank can be installed, slab on grade, outside. Again, it must be properly set and piped. And use a good fuel additive.

What specifically is wrong with the chimney? Has it been inspected, and recommendations made?

You could go with LPG and a mod con, but do the math first.

A good 2 Stage or inverter type heat pump is not an unwise decision IMO, but for myself, it would never be my sole heat source. My situation is similar to yours, and I'll upgrade my oil boiler. I'll also upgrade my 20 year old R22 system to a 2 Stage heat pump. The hydronic baseboard heat will be Stage 3. The boiler will still provide DHW.